Catalogue en ligne Bibliothèque Ecole Nationale Polytechnique d'Alger

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11854–11855

Titre :	Comment on the “dynamic simulation of sorption enhanced reaction processes for biodiesel production”
Type de document :	texte imprimé
Auteurs :	Pedro Sa Gomes, Auteur ; Viviana M. T. M. Silva, Auteur ; Alirio E. Rodrigues, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11854–11855
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Sorption Dynamic
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100488j

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11848-11853

Titre :	Acoustical and compressibility parameters of glycylglycine − FeCl3 in aqueous ethanol mixture at T = (293.15, 303.15, and 313.15) K
Type de document :	texte imprimé
Auteurs :	M. S. Santosh, Auteur ; D. Krishna Bhat, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11848-11853
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Compressibility
Résumé :	Ultrasonic velocity measurement is a reliable procedure that allows quick and easy determination of solvent concentrations in mixtures. This paper presents data of ultrasonic velocities and isentropic compressibilities of (glycylglcyine-FeCl3) in aqueous ethanol mixture at T= (293.15, 303.15, and 313.15) K. Various acoustical parameters were calculated, because of their importance in the study of specific molecular interactions. A less-compressible phase of the fluid and a closer packing of molecules is observed with changes in the intermolecular free length. Quantitative investigation suggests that the mixing of ethanol with an aqueous glycylglycine-FeCl3 solution causes the rupture of hydrogen bonds, with increasing δκS and Lf values (where the former represents the change in isentropic compressibility and the latter represents the intermolecular free length). Theoretically computed values of isentropic compressibility in the studied mixture using different models indicate the superiority of the very complex procedure.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437889

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11841-11847

Titre :	Polyvinyl chloride and halogen - free electric wires thermal decomposition
Type de document :	texte imprimé
Auteurs :	Juan A. Conesa, Auteur ; Julia Molto, Auteur ; Rafael Font, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11841-11847
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Thermal decomposition Wire
Résumé :	A kinetic model for the pyrolysis and combustion of PVC and halogen-free electric wires has been obtained. One set of parameters can explain all the experiments at the different atmospheres and at the three different heating rates used. Thermal analysis of different parts of the cable, cover, insulation and conductive metal, both separately and combined, has allowed for understanding of the interaction between the different materials.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437888

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11837-11840

Titre :	Hydrogenation of maleic anhydride to succinic anhydride over Ni / HY - Al2O3
Type de document :	texte imprimé
Auteurs :	Jie Li, Auteur ; Wei-ping Tian, Auteur ; Li Shi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11837-11840
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydrogenation
Résumé :	The hydrogenation of maleic anhydride to succinic anhydride was carried out over Ni/Al2O3-HY catalysts. The catalysts, which contained 3-30 wt % Ni, were prepared via a kneading method. The catalysts were characterized by an array of techniques, including X-ray diffraction (XRD) and H2 temperature-programmed reduction (TPR). The nature of the Ni species on the support, and their interaction with the support, were studied. XRD and TPR studies showed that nickel was present as Ni2+ and Ni3+ species on the support, and that there was no elemental nickel (Ni0) in the unreduced samples. Pretreatment using pure H2 at different temperatures affected the reactivity. Pretreatment at 350 °C for 3 h was the best among the conditions tested.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437887

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11832–11836

Titre :	Kernel generalization of PPCA for nonlinear probabilistic monitoring
Type de document :	texte imprimé
Auteurs :	Ge, Zhiqiang, Auteur ; Zhihuan Song, Auteur
Année de publication :	2011
Article en page(s) :	pp.11832–11836
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Surveillance
Résumé :	For probabilistic monitoring of nonlinear processes, the traditional probabilistic principal component analysis (PPCA)-based monitoring method is generalized through the kernel method. Thus, a probabilistic kernel PCA method is proposed for process monitoring in the present paper. Different from the traditional PPCA method, the new approach can successfully extract the nonlinear relationship between process variables. On the basis of the proposed nonlinear probabilistic monitoring approach, the monitoring performance of nonlinear processes can be effectively improved. To demonstrate the feasibility and efficiency of the proposed method, a case study on the Tennessee Eastman (TE) benchmark process is provided.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437886

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11825–11831

Titre :	A new pyrolysis of metal hydroxide - mixed waste biomass with effective chlorine removal and efficient heat recovery
Type de document :	texte imprimé
Auteurs :	Shigeya Hayashi, Auteur ; Hiroshi Amano, Auteur ; Toyoaki Niki, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11825–11831
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydroxide Biomass
Résumé :	Waste woody biomass samples including poly(vinyl chloride) (PVC), which were mixed with metal hydroxides as additives, were carbonized at 500 °C to investigate the catalytic effect of the additives on pyrolysis products and to elucidate the mechanism of biomass carbonization. The results showed that the yield of char significantly increased, whereas tar evolution was suppressed by the influence of metal hydroxides, even with the coexistence of PVC. Moreover, the interaction behaviors between the biomass structure including PVC and metal hydroxides were further investigated. It was clarified that the dehydration reaction to form a cross-linked structure in biomass by the effect of metal ion and the neutralization reaction between PVC and metal hydroxides were simultaneously occurred during the carbonization. The presence of chlorine component, which is one of corrosive substances, was confirmed in char structure by chlorine analysis. Therefore, a flushing method with warm and cold water was applied, to investigate the possibility of chlorine removal. The results showed that flushing with warm water and cold water are both effective for the removal of chlorine component in the char. Finally, the new pyrolysis process of NaOH-mixed waste biomass materials, including proposed heat recovery facilities, can be suggested as an effective system of biomass utilization for energy savings and CO2 reduction.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1008234

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11814–11824

Titre :	Two - dimensional modeling of the transport phenomena in the adsorber during pressure swing adsorption process
Type de document :	texte imprimé
Auteurs :	Xingang Zheng, Auteur ; Yingshu Liu, Auteur ; Wenhai Liu, Auteur
Année de publication :	2011
Article en page(s) :	pp.11814–11824
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Transport phenomena Adsorption process
Résumé :	In this study, a two-dimensional model is established to simulate the pressure swing adsorption process. It is the first time a two-dimensional model has been used to study the transport phenomena occurring inside the adsorber during the PSA process with consideration of the heat effect, gas compressibility, radial porosity, and dead volumes. Parts of the results have been compared with the results either from experiments or from the references, which show the model can give a favorable prediction. The 2D simulation results clearly show the concentration distribution and its propagation with time, and concentration maldistribution induced by a nonuniform packing. The velocity, pressure, and temperature distribution is also presented in the paper. A brief discussion of the effect of maldistribution, pressure drop (resistance of porous media) and sorption heat et al. on the concentration distribution is made. As expected, the results visually show that the maldistribution and sorption heat will reduce the adsorber performance. It is also found that a moderate pressure drop is useful for the performance improvement of an adsorber, because it will help bring evenly distributed flow field. There is independent concentration wave velocity, temperature wave velocity, and gas velocity, and during the adsorption step, the concentration wave velocity is larger than that of temperature wave until they coincide with each other. The gas velocity is much larger than the other two velocities. The two-dimensional simulation is found to be very useful for a better understanding of the dynamic sorption and separation process in an adsorber. The results of further research are capable to guide or optimize the design of adsorber configurations.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100474n

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11809–11813

Titre :	Alkanolamine ionic liquids and their inability to dissolve crystalline cellulose
Type de document :	texte imprimé
Auteurs :	Andre Pinkert, Auteur ; Kenneth N. Marsh, Auteur ; Shusheng Pang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11809–11813
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Ionic liquids Crystalline Cellulose
Résumé :	The purpose of this research note is to report on the inability of alkanolammonium ionic liquids to dissolve crystalline cellulose, supporting the claims we make in an associated commentary paper, “Reflections on the Solubility of Cellulose” (Pinkert et al., Ind. Eng. Chem. Res. 2010, 49, DOI: 10.1021/ie1006596). Four organic acids (formic acid, acetic acid, malonic acid, and citric acid) and five amines (ethanolamine, diethanolamine, triethanolamine, propan-1-olamine, and diallylamine) were selected for the synthesis of 17 protic ionic liquids. The products were characterized by 1H nuclear magnetic resonance spectroscopy, infrared spectroscopy, thermogravimetric analysis, and Karl Fischer titration.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101250v

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11801–11808

Titre :	A novel theory for predicting critical constants and the a function for pure polymers
Type de document :	texte imprimé
Auteurs :	Chorng H. Twu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11801–11808
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Polymers
Résumé :	The cubic equation of state (CEoS) requires critical temperature (Tc), critical pressure (Pc), and the alpha (α) function for all components including polymers before it can be used for the prediction of phase behavior and thermodynamic properties for the system. For nonpolymers or conventional components, Tc, Pc, and α usually are available in databanks. However, this is not the case for polymers since their critical point is not measurable and they lack vapor pressures for the derivation of the α function. As a result, the task of finding CEoS critical constants as well as the α function for polymers becomes extremely challenging in the case of polymeric systems. A rigorous theory requiring only the liquid density data of the pure polymer is successfully developed in this work for the accurate prediction of the critical temperature, the critical pressure, and the α function for the pure polymer for use in all types of cubic equations of state. The proposed theory extends the application of cubic equations of state to polymer systems in a very simple fashion.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101474d

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11797–11800

Titre :	Experimental determination of the equilibrium conditions of binary gas hydrates of cyclopentane + oxygen, cyclopentane + nitrogen, and cyclopentane + hydrogen
Type de document :	texte imprimé
Auteurs :	Du Jianwei, Auteur ; Liang Deqing, Auteur ; Li Dongliang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11797–11800
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Binary gas Cyclopentane Hydrogen
Résumé :	In this work, four-phase hydrate equilibrium data for each of the systems cyclopentane (CP) + water + hydrogen, CP + water + nitrogen, and CP + water + oxygen were measured and are reported in the temperature range of 281.3−303.1 K and the pressure range of 2.27−30.40 MPa. Measurements were made using an isochoric method. Experimental data on the equilibrium conditions of the two systems nitrogen + water and hydrogen + water with CP are reported over a previously uninvestigated extended temperature span. The hydrate dissociation data for the CP + water + hydrogen system are compared with some selected experimental data from the literature, and the acceptable agreement demonstrates the reliability of the experimental method used in this work. Finally, the first quadruple phase equilibrium data in the ternary system CP + water + oxygen have been achieved.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101339j

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11785–11796

Titre :	Biodiesel production from canola in western australia : energy and carbon footprints and Land, water, and labour requirements
Type de document :	texte imprimé
Auteurs :	Ferry Rustandi, Auteur ; Hongwei Wu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11785–11796
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Biodiesel Energy Carbon
Résumé :	This study evaluates the energy and carbon footprints and land, water, and labor requirements of biodiesel production from canola in Western Australia (WA). The results show that canola-based biodiesel leads to limited energy profit and CO2 equivalent (CO2-e) emissions savings. Even when all byproduct are utilized, a relatively low output/input energy ratio of 1.72 and a CO2-e emissions savings of only 0.52 kg of CO2-e/L of biodiesel are obtained under the WA conditions considered in this study. A land requirement of 1.66 × 10−3 ha/L of biodiesel means that canola-based biodiesel seems to also be limited to <2% replacement of total diesel consumption in WA’s transport sector to avoid significant competition with food production for arable land. When some of the biodiesel is invested back into the production process to make the process independent of nonrenewable fuels, the competition for arable land use is even more severe, rendering it unfeasible to replace diesel fuel by the net biodiesel. Also, there would not be enough net biodiesel to support the transport activities that are usually supported by diesel fuel in the WA transport sector, and no CO2-e emissions savings would be achieved from replacing diesel fuel by net biodiesel. Overall, canola-based biodiesel is not sustainable to replace a significant fraction of diesel consumption in the WA transport sector. It can only play a limited role by offering some energy and CO2-e emissions savings and by providing immediate opportunities for introducing new transport fuels in the marketplace and developing familiarity among the consumers in our transition to a future sustainable biofuel supply.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1013162

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11778–11784

Titre :	Development and performance of CaO/La2O3 sorbents during calcium looping cycles for CO2 capture
Type de document :	texte imprimé
Auteurs :	Cong Luo, Auteur ; Ying Zheng, Auteur ; Ning Ding, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11778–11784
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Sorbents
Résumé :	The calcium looping cycles method has been identified as an attractive method for CO2 capture during coal combustion and gasification processes. However, it is well-known that the capture capacity of CaO undergoes a rapid decrease after mutiple cycles. In order to improve the stability of CO2 capture capacity in CaO, this paper focuses on the development and performance of the synthetic CaO/La2O3 sorbents for calcium looping cycles.The sorbents were synthesized by three different methods: dry physical mixing, wet chemistry, and sol−gel combustion synthesis (SGCS). Their multicyclic CO2 capture capacity and the effect of the additive La2O3 were investigated in a fixed bed reactor system. The results indicate that the additive of La2O3 plays a positive role in the carbonation/calcination reactions, and the SGCS-made synthetic sorbent is composed of ultrafine well-dispersed hollow structured particles which are beneficial to the gas-phase diffusion on the surface area and can prevent small CaO particles from agglomeration effectively. As a result, the novel synthetic sorbent with the molar ratio of Ca to La of 10:1 made by the SGCS method provides the best performance of a carbonation conversion of 72% under mild calcination conditions and a carbonation conversion of 36% under severe calcination conditions (high temperature and high CO2 concentration) after 20 cycles.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1012745

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11764–11777

Titre :	Perfumery Radar: : a predictive tool for perfume family classification
Type de document :	texte imprimé
Auteurs :	Miguel A. Teixeira, Auteur ; Oscar Rodriguez, Auteur ; Alirio E. Rodrigues, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11764–11777
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Perfumery radar
Résumé :	The classification of perfumes into olfactory families has been done for years on the basis of sensorial analysis or odor descriptors, but none of these methods has attained universal acceptance. In this work is presented a methodology called perfumery radar (PR) that predicts the classification of perfumes using the olfactive families that perfumers use. The PR introduces some scientific basis, reducing the arbitrariness of perfume classification to the empirical classification of pure odorants. The odor intensity of pure fragrances in a liquid mixture is predicted using the odor value concept, considering molecular interactions between components. Radar plots are used to represent olfactory families and transform quantitative information into qualitative. Perfumery radars have been obtained for several commercial perfumes and compared with existing experimental classifications. Another validation using headspace GC analysis was also performed with satisfactory results. It is shown that the PR methodology is able to predict the primary olfactive family of perfumes, according to the experimental classification given by perfumers. The prediction of secondary and tertiary families agreed with some of the empirical classifications in most cases, although there was little agreement among those at this level.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101161v

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11760–11763

Titre :	Oxidative Desulfurization of Dibenzothiophene Catalyzed by Ionic Liquid [BMIm] HSO4
Type de document :	texte imprimé
Auteurs :	Wei Zhang, Auteur ; Ke Xu, Auteur ; Qian Zhang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11760–11763
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Ionic liquid Catalyst Oxidative
Résumé :	An acidic ionic liquid N-butyl-N-methylimidazolium hydrogen sulfate ([BMIm]HSO4) was applied as extractant and catalyst for the oxidative desulfurization of dibenzothiophenes (DBT) in the presence of H2O2 in model oil. Several parameters, e.g., catalyst amount, hydrogen peroxide quantity, reaction time, and temperature, were investigated in detail. The catalytic oxidative desulfurization rate can reach 100% for DBT in model oil. The ionic liquid [BMIm]HSO4 can be recycled 5 times with only a slight reduction in activity.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100957k

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11752–11759

Titre :	Investigation of operation regimes in a multistage internal - loop airlift reactor
Type de document :	texte imprimé
Auteurs :	Wei Yu, Auteur ; Tiefeng Wang, Auteur ; Malin Liu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11752–11759
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Multiphase Airlift reactor
Résumé :	Multiphase internal-loop airlift reactor is effective in reducing liquid back-mixing. To further improve the distribution of solid particles in different stages, a novel interstage internal, i.e., a perforated plate with several long tubes, was used to provide a separate flowing path for gas and slurry phases. With this novel internal, a gas layer was formed between the two adjacent stages and had a significant effect on the operation regimes. In this work, the effects of the opening ratio of the internal and superficial gas and liquid velocities on the operation regimes were experimentally studied for both cocurrent and countercurrent flows. The experimental results show that the superficial gas and liquid velocities have significant effects on the operation regimes. The effect of the opening ratio for gas channels on the operation regimes was more significant than that of the opening ratio for liquid channels. Compared with the traditional perforated plate internal, the novel internal showed better performance for operation flexibility. The regime map was obtained from the calculated gas layer height with the mathematical model proposed in our previous work and was in good agreement with the experiential results. The results in this work can provide guidance for design and scaleup of the multistage reactors.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100746z

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11741–11751

Titre :	Novel poly (N - vinylcaprolactam - co - 2 - (diethylamino)ethyl methacrylate) gels : characterization and detailed investigation on their stimuli - sensitive behaviors and network structure
Type de document :	texte imprimé
Auteurs :	Elcin Cakal, Auteur ; Selva Cavus, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11741–11751
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Poly Homopolymer gel
Résumé :	Poly(N-vinylcaprolactam-co-2-(diethylamino)ethyl methacrylate), P(VC-co-DEAEMA), gels were synthesized in ethanol by using free radical cross-linking polymerization method at 60 °C for 24 h in the presence of azobis(isobutyronitrile) (AIBN) as initiator. Homopolymer gels of N-vinylcaprolactam (PVC) and 2-(diethylamino)ethyl methacrylate (PDEAEMA) were also synthesized at the same conditions and used for comparison purposes. In the synthesis of homopolymer and copolymer gels, ethylene glycol dimethacrylate (EGDMA) and allyl methacrylate (AMA) cross-linking agents were employed in order to determine the effects of cross-linker type on the equilibrium swelling value (ESV) and percentage of gelation (PG). pH and temperature sensitivities of gels were investigated for both cross-linkers, and network parameters of gels were also found. In addition, detailed characterization studies were performed by Fourier transform infrared and scanning electron microscopy techniques. It was observed that PVC gel had the lowest PG and highest ESV. Compared to EGDMA, AMA increased thee percentage of gelation and decreased the equilibrium swelling value of gels. pH-sensitive profiles of gels were substantially different from each other and strongly dependent on DEAEMA content. Copolymer gels containing the highest mole percentage of N-vinylcaprolactam (95%) showed non-Fickian and Fickian swelling behavior at pH 7.4 for EGDMA and AMA cross-linkers, respectively. It was found that both monomer concentration and cross-linker type affected the polymer−solvent interaction parameters (χ), mesh size (ζ), and experimental average molecular mass between the cross-links (McE) of gels.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1007097

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11732-11740

Titre :	Palm oil mill effluent (POME) characteristic in high crop season and the applicability of high - rate anaerobic bioreactors for the treatment of POME
Type de document :	texte imprimé
Auteurs :	Phaik Eong Poh, Auteur ; Wei-Jin Yong, Auteur ; Mei Fong Chong, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11732-11740
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Bioreactor Anaerobe
Résumé :	Palm oil mill effluent (POME) is a wastewater generated from palm oil milling activities which requires effective treatment before discharge into watercourses due to its highly polluting properties. The characterization of wastewater is the essential step in the design of any wastewater treatment plant (WWTP) in the industry as conducting pilot-scale tests to obtain design and operating parameters is time-consuming and expensive. Characterization of POME had been conducted in various studies which only involve parameters that were listed as discharge standards by local environmental authorities and those that were significant to the results of the chosen treatment methods. Other important parameters that were seldom considered in the characterization of POME are as follows: total phosphorus (TP), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), total volatile solids (TVS), volatile suspended solids (VSS), lignin and sulfate concentrations, and toxicity. These parameters are very important in determining the suitable treatment method for industrial-scale WWTP designs besides detecting the operational problems of the selected treatment system due to the characteristics of POME. This would also ensure a proper process design and equipment sizing for POME treatment systems. Therefore a comprehensive POME characteristic study was conducted in the present research with two main objectives: (i) to obtain a complete, up to date, and representative characteristic of POME which is important for treatment method selection, process design, and equipment sizing for industrial-scale WWTP and (ii) to evaluate the suitability of POME to be treated anaerobically on the basis of the characteristic study. POME characteristics sampled from Golconda palm oil mill at high crop season was found to have deviated at approximately ±20-50% from the values recorded during low crop season. An overall characteristic of POME obtained from this study indicated that the biochemical oxygen demand (BOD) concentration in POME was 49000 mg/L; chemical oxygen demand (COD) was 79000 mg/; total volatile solids (TVS) concentration was 42600 mg/L; and COD:N:P ratio of POME was 250:2.9:3.2. The POME characteristic obtained in this study indicated that POME treatment using anaerobic systems was a viable option due to the high biodegradability of the POME and the versatility of high-rate anaerobic bioreactors to cope the variation and fluctuation of POME characteristics. Furthermore, the introduction of the clean development mechanism (CDM) encourages the utilization of high-rate anaerobic bioreactors for POME treatment and methane capture to earn certified emission reduction (CER) credits as a source of revenue.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437874

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11724-11731

Titre :	Transport phenomena of falling liquid film flow on a plate with rectangular holes
Type de document :	texte imprimé
Auteurs :	Ming Zhu, Auteur ; Chun Jiang Liu, Auteur ; Wei Wei Zhang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11724-11731
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Film flow Liquid film Transport process
Résumé :	Falling liquid film flow is a sort of ubiquitous transport phenomenon occurring in chemical engineering. Fundamental research on the flow and mass transfer behavior of falling liquid film flow on plates with different structures can help engineers to develop more efficient equipment. In this paper, falling liquid film flow on a plate with rectangular holes is investigated with both numerical and experimental methods. Mass transfer experiments show that opening rectangle-shaped narrow holes on a plate can enhance the mass transfer efficiency. Compared to an ordinary plate, the vapor—liquid mass transfer rate on a holed plate can be increased by 10-20%. To analyze the detailed flow and mass transfer behavior, the computational fluid dynamics model (CFD) based on the volume of fluid (VOF) method is developed. In this model, the Marangoni effect induced by mass transfer is considered. The new model was demonstrated to give more satisfactory results than the previous model.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437873

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11714-11723

Titre :	Numerical analysis of solid − liquid two - phase flow on sandstone wastewater of hydropower stations in a rectangular sedimentation tank
Type de document :	texte imprimé
Auteurs :	X. Ling Wang, Auteur ; Tao Li, Auteur ; Jian Lang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11714-11723
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Settling pond Sedimentation tank Waste water Two phase flow Numerical simulation Numerical analysis
Résumé :	The lack of knowledge on water flow and particle behavior of sandstone wastewater in sedimentation tanks of hydropower stations is a significant challenge for the design of these processes. In this study, the Euler-Lagrange two-phase model was applied to study the flow, sedimentation, and particle trajectories in a two-stage rectangular tank that is divided into two sections with different hydraulic retention times. The interfacial momentum transfer, buoyant force, and the collision force were considered, and the Lagrange approach was employed to determine the particle trajectories of the particles. The flow patterns, removal efficiency of the particles, and particle trajectories along the tank were investigated. The experimental and numerical results revealed that the two-stage rectangular tank is efficient in dealing with high turbidity sandstone wastewater. In addition, the simulated removal efficiencies were in good agreement with the experimental results. Last, the sensitivity of particle behavior to the collision force was studied, and the effect of the baffle length on particle settling in the rectangular sedimentation tank was evaluated.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437872

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11708–11713

Titre :	Isothermal dehydration of the poly (acrylic - co- methacrylic acid) hydrogel
Type de document :	texte imprimé
Année de publication :	2011
Article en page(s) :	pp. 11708–11713
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Résumé :	The isothermal thermogravimetric dehydration curves of an equilibrium swollen hydrogel of a poly(acrylic-co-methacrylic acid) (PAM) hydrogel at temperatures in the range of 293−313 K were determined. By applying a model-fitting method, it was established that the isothermal dehydration of equilibrium swollen PAM hydrogel was a phase-boundary-controlled process with kinetics limited with the rate of the decrease of the area of hydrogel pores. Based on the results of a differential isoconversional method, it was concluded that, in the degree of dehydration range of 0.1 ≤ α ≤ 0.8, the activation energy is independent of the degree of dehydration, whereas, for α > 0.8, it decreases with increasing degree of dehydration. It is assumed that the kinetics of the isothermal dehydration of hydrogel is determined with the changes in the fluctuation structure, because of dehydration. It is established that the dominant effect on the kinetics of dehydration of PAM hydrogel in the range of 0.1 ≤ α ≤ 0.8 is referred to as a so-called “λ-relaxation process”, whereas in the range of α ≥ 0.8, it is the so-called “α-relaxation process” in hydrogels.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie9016896

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11697–11707

Titre :	Molecular sieving separation of hexane isomers within nanocomposite (B) - MFI - alumina hollow fiber membranes : a modeling study
Type de document :	texte imprimé
Auteurs :	Z. Deng, Auteur ; M. Pera-Titus, Auteur ; Y. Guo, Auteur
Année de publication :	2011
Article en page(s) :	pp.11697–11707
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Nanocomposite Fiber membranes Modeling
Résumé :	High quality nanocomposite B-MFI hollow fibers were successfully prepared by pore-plugging hydrothermal synthesis. The incorporation of boron into the MFI structure modifies the n-hexane/2,2-dimethylbutane vapor separation properties of the membranes, with the materials improving the n-hexane/2,2-dimethylbutane intrinsic separation factors of Al-MFI by a factor of 2 (up to a value of 200) at comparable conditions. The permeation performance of the membranes is essentially governed by a molecular sieving mechanism driven by preferential diffusion of n-C6 and configurational diffusion effects favoring n-hexane adsorption from n-hexane/2,2-dimethylbutane mixtures. A strong confinement scenario for surface diffusion of both n-hexane and 2,2-dimethylbutane seems to prevail.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101566q

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11689-11696

Titre :	Comparing performance of CPO and IRMOF membranes for gas separations using atomistic models
Type de document :	texte imprimé
Auteurs :	Seda Keskin, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11689-11696
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Modeling
Résumé :	Atomically detailed simulations were used to present the first information about the performance of isostructural metal organic frameworks (MOFs) having different metal sites, CPO-27-M (M = Ni, Co), as adsorbents and membranes for separation of CH4/H2 mixtures. Adsorption isotherms and diffusion coefficients of both single components and CH4/H2 mixtures were computed, and this data was used to predict adsorption selectivity, diffusion selectivity, ideal selectivity, and membrane selectivity of CPO materials at various pressures and feed compositions. Separation performance of CPO materials was compared with other MOFs such as IRMOF-1, -8, -10, -14 and with well-known nanoporous materials, such as zeolites MFI, LTA, and CHA and carbon nanotubes. Results showed that CPO materials exhibit higher adsorption selectivity and membrane selectivity than IRMOFs. These results give insight into the physical properties of MOFs that will be desirable in tuning the structure of MOFs for specific gas separations.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437869

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11682–11688

Titre :	Adsorption of Pb2+ by alkali - treated citrus limetta peels
Type de document :	texte imprimé
Auteurs :	Umesh Suryavanshi, Auteur ; Sanjeev R. Shukla, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11682–11688
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Adsorption
Résumé :	The biomass Citrus limetta fruit peels was subjected to Pb2+ adsorption from aqueous PbNO3 solutions of different concentrations. Pretreatment of the biomass using cold alkali enhanced the adsorption by 87% even after considering the percentage weight loss. The biomass was characterized by scanning electron microscopy (SEM), electrokinetic analysis, and FT-IR spectroscopy. The equilibrium sorption capacity was observed to be 630 mg/g and the adsorption obeyed the Langmuir, Dubinin−Radushkevich (D−R), and ion-exchange models. The optimum pH and biomass concentration for maximum adsorption capacity were observed to be 4.5 and 0.1 g/L, respectively. Almost 80% sorption takes place within the first 15 min. The role of carboxylic and other functional groups was revealed to be ion exchange with a 1:2 stoichiometry between Pb2+ and carboxylic groups.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101491w

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11676–11681

Titre :	Prediction of Self-Diffusivity in Multicomponent Polymeric Systems Using Shell-Like Free Volume Theory
Type de document :	texte imprimé
Auteurs :	Hidenori Ohashi, Auteur ; Taichi Ito, Auteur ; Takeo Yamaguchi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11676–11681
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Multicomponent Polymeric
Résumé :	Shell-like free volume theory for multicomponent polymeric systems was developed. Molecular-diffusive motion in polymeric systems is due to a large number of microscopic molecular collisions with adjacent molecules. To embody this idea, a shell-like free volume is defined as the free space surrounding the penetrant molecule that emerges from molecular collisions. The common description of molecular collisions allows the shell-like free volume theory to include multicomponent systems. An advantage of the theory is it can estimate molecular self-diffusivity in multicomponent polymeric systems using only pure component parameters of the constituents and no arbitrary parameter or empirical equation. The required parameters can be derived from viscoelastic properties and quantum chemical calculations. Moreover, by comparing experimental and theoretical values, we find that, insofar as no strong interaction is included, this model can fairly predict penetrant self-diffusivities in several multicomponent systems with a wide range of compositions and different types of molecules, even though the model contains no adjustable parameters.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101299q

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11667-11675

Titre :	Preparation and pervaporation property of chitosan membrane with functionalized multiwalled carbon nanotubes
Type de document :	texte imprimé
Auteurs :	Shi Qiu, Auteur ; Liguang Wu, Auteur ; Guozhong Shi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11667-11675
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Membrane separation Pervaporation Preparation
Résumé :	This study was designed to prepare functionalized multiwalled carbon nanotubes (MWNTs-COOH) incorporated chitosan membrane for separation of ethanol/water mixtures by pervaporation. The pristine MWNTs were treated by mixed acid and then functionalized by diisobutyryl peroxide. The structure and property of the functionalized MWNTs were characterized by Fourier transform infrared and Raman spectroscopies and transmission electron microscopy. A series of functionalized MWNTs incorporated chitosan membranes were prepared by solution blending method. The swelling degree of the resulting membranes in ethanol/water mixtures was 6 times that of the pristine chitosan membrane. The permeation flux of the membranes increased significantly with increasing functionalized MWNTs content in blend membrane matrix in pervaporation. On the basis of the experiments of sorption equilibrium, the solubility and the diffusion coefficient of membranes in water, ethanol, and 90% ethanol/water mixtures were obtained. Compared with the calculated diffusion coefficient (D90), the measured diffusion coefficient (D90T) in 90% ethanol/water mixtures was higher, taking M(2) for an example, D90 was 0.193 x 10-6 m2/s, and D90T was 0.41 × 10-6 m2/s, which indicated the functionalized MWNTs were more prone to increased water permeation when ethanol and water penetrated into the membrane simultaneously. In addition, effects of MWNTs content in the membrane matrix and operating temperature on pervaporation performances were investigated. After introducing functionalized MWNTs, the Arrhenius activation parameters for the total permeation decreased from 28.15 to 12.91 kJ/mol, which indicated that the carbon nanotubes filled membranes were easier to penetrate and exhibited higher flux performance than a pristine membrane.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437866

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11661-11666

Titre :	Purification rate of uranyl nitrate hexahydrate crystal for transuranium elements on isothermal sweating phenomenon
Type de document :	texte imprimé
Auteurs :	Masaumi Nakahara, Auteur ; Kazunori Nomura, Auteur ; Tsutomu Koizumi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11661-11666
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Purification
Résumé :	For the purpose of further increasing decontamination performance, the purification behavior of uranyl nitrate hexahydrate (UNH) crystals was studied in the static system. The approach to purification of UNH crystals recovered from the irradiated fast reactor core fuel using a dissolver solution was examined by an isothermal sweating process, which involves heating to the melting point of the crystal. Since transuranium (TRU) elements were present as liquid impurities in the UNH crystal, their decontamination factors (DFs) were improved using this process. The DFs of Cs and TRU elements for the UNH crystals had a tendency to increase with time and were kept virtually constant by 240 min. Not having been precipitated as Cs2Pu(NO3)6 during the crystallization, Pu remained in the mother liquor and was removed by the sweating process. The purification rate coefficients of UNH crystals for Cs and TRU elements were calculated using these experimental data. These values for Pu, 137Cs, 241Am, and 242Cm were evaluated to be 2.13 x 10-4, 2.73 × 10-4, 2.1 × 10-4, and 3.13 x 10-4 s-1 at 57 °C, respectively.
DEWEY :	660
ISSN :	0888-5885

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11652–11660

Titre :	Preparation and characterization of immobilized chelate extractant in PVA gel beads for an efficient recovery of copper (II) in aqueous solution
Type de document :	texte imprimé
Auteurs :	Takashi Kobayashi, Auteur ; Makoto Yoshimoto, Auteur ; Katsumi Nakao, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11652–11660
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Aqueous Solution Copper
Résumé :	To efficiently recover metals from aqueous solutions using solvent extractions, the various types of immobilized chelate extractants have been proposed because the conventional liquid−liquid extraction requires a large quantity of organic solvents and a complicated equipment system. As a basis of developing a safer, simpler, and more environment-friendly chelate extraction process, in the present work, a commercial chelate extractant, 5-dodecylsalicylaldoxime in kerosene (LIX860-I), was originally immobilized in the polyvinylalcohol (PVA) gel beads. The PVA gel beads prepared were used for recovering copper(II) in the aqueous solutions containing cupric sulfate (0.4−0.7 wt % in CuSO4·5H2O). The gel beads of 5 mm in mean diameter were packed in a column of 5.4 cm in diameter for extracting copper(II) from the solution to the gel beads without direct contact of the solvent with the aqueous solution. The extraction was carried out in an expanded bed 8.2 cm in height by circulating the copper(II)-containing solution upward through the column. Copper(II) in the solution could steadily be extracted into the gel beads, although the process required a relatively long time due to the diffusion resistance of copper(II) in the gel phase. The progressive change of the extractant in a bead was found to be elucidated by the shrinking core model. A practical extraction process was suggested to employ the earlier stage of the extraction process where the rate was relatively high. The estimated chelation equilibrium between copper(II) and the chelate extractant in the gel beads was almost the same as that in the liquid−liquid extraction. The sorption equilibrium of copper(II) into the bead was well-described by the Langmuir-type isotherm, suggesting almost perfect utilization of the extractant immobilized in the bead. The copper(II) extracted in the gel beads was completely recovered by stripping with an aqueous sulfuric acid solution of a high concentration of 225 g/L. The gel beads could be reused at least three times with negligible leakage of the LIX860-I and no damage to the beads. The PVA gel beads are recommended to be kept in the column and cyclically utilized by extracting copper(II) from the aqueous solution and then stripping it.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101113s

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11645-11651

Titre :	Recovery of trace rare earths from high - level Fe3 + and Al 3+ waste of oil shale ash (Fe - Al - OSA)
Type de document :	texte imprimé
Auteurs :	Hualing Yang, Auteur ; Wang, Wei, Auteur ; Dongli Zhang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11645-11651
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Ash
Résumé :	An experimental investigation was undertaken to study the high-efficient and clean enrichment of trace rare earths from high-level Fe3+ and Al3+ waste of oil shale ash (Fe-Al-OSA). The optimum leaching temperature, ratio of solid to liquid, acidity, and reaction time for Fe-Al-OSA were 30 °C, 1:7, 50% (v/v), and 1 h by the Taguchi method, respectively, and the leaching rate of rare earths has been reached up to 96.24%. The optimal extraction conditions for removing Fe3+ from leaching liquor of Fe-Al-OSA were as follows: the organic phase was 30% N235 + 10% isooctyl alcohol (ROH) + 60% n-heptane, acidity of aqueous phase was about 3.00 mol/L, and phase ratio (Vo:Vw) was 8:5. More than 92.09% of Fe3+ was recovered by using countercurrent extraction process with 4—5 stages. The 99.76% of high pure Fe byproduct was obtained by stripping the loaded N235 organic phase, and it can be used as chemistry pure reagent directly. After adjusting the pH of the raffinate to 6.00 with MgO and saturated Na2CO3 solution, all of the Al3+ and rare earths were transformed to hydroxide precipitation and separated from the solution, together with other small amounts of coexisting metal ions such as Ca2+ and Mg2+. Then, the precipitation was washed, collected, and dissolved by HNO3. Rare earths can be separated from the solution by solvent extraction with 30% tributyl phosphate (TBP) +70% n-heptane at the phase ratio (Vo:Vw) 3:2. The recovery rate of rare earths from Fe-Al-OSA has reached 86.30% in the whole separation process. The residual Al3+ in solution was recycled. This work shows that such a treatment route is one kind of highly efficient and clean method for separating Fe3+ and Al3+, and concentrating rare earths from Fe-Al-OSA. The solid waste (Fe-Al-OSA) from the refinery can also be utilized effectively to solve the ecological and environmental problems caused by the waste heap.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437863

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11633-11644

Titre :	Bivariate extension of the quadrature method of moments for batch crystallization models
Type de document :	texte imprimé
Auteurs :	Shamsul Qamar, Auteur ; Saima Noor, Auteur ; Qurrat ul Ain, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11633-11644
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Modeling Crystallization Batchwise
Résumé :	This Article presents a bivariate extension of the quadrature method of moments for solving two-dimensional batch crystallization models involving crystals nucleation, size-dependent growths, aggregation, and dissolution of small nuclei below certain critical size in a dissolution unit. In this technique, orthogonal polynomials of lower order moments are used to find the quadrature abscissas (points) and weights. Several benchmark problems with different combinations of processes are considered in this Article. The accuracy and efficiency of the proposed method are validated against the analytical solutions and the high-resolution finite volume scheme. Excellent agreements were observed in all test problems. It was found that the current method is very efficient and accurate as compared to the high-resolution finite volume scheme.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437862

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11620-11632

Titre :	Molecular thermodynamic modeling of mixed solvent solubility
Type de document :	texte imprimé
Auteurs :	Martin D. Ellegaard, Auteur ; Jens Abildskov, Auteur ; John P. O’Connell, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11620-11632
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Solubility Mixed solvent Modeling
Résumé :	A method based on statistical mechanical fluctuation solution theory for composition derivatives of activity coefficients is employed for estimating dilute solubilities of 11 solid pharmaceutical solutes in nearly 70 mixed aqueous and nonaqueous solvent systems. The solvent mixtures range from nearly ideal to strongly nonideal. The database covers a temperature range from 293 to 323 K. Comparisons with available data and other existing solubility methods show that the method successfully describes a variety of observed mixed solvent solubility behaviors using solute-solvent parameters from global regression of ternary data as well as predictions based on pure solvent solubilities with an average error of about 10% on mole fractions.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437861

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11614–11619

Titre :	Gas hydrate formation process for capture of carbon dioxide from fuel gas mixture
Type de document :	texte imprimé
Auteurs :	Xiao-Sen Li, Auteur ; Zhi-Ming Xia, Auteur ; Zhao-Yang Chen, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11614–11619
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Gas Carbon Dioxide
Résumé :	To determine the suitable operating conditions for the hydrate-based CO2 separation process from a fuel gas mixture, the hydrate nucleation and growth kinetics of the simulated fuel gas (39.2 mol % CO2/H2 gas mixture) in the presence of tetra-n-butyl ammonium bromide (TBAB) are investigated. The experiments were conducted at the TBAB concentration range of 0.14−1.00 mol %, the temperature range of 275.15−282.45 K, the driving force range of 1.00−4.50 MPa, the gas/liquid phase ratio range of 0.86−6.47, and the hydrate growth time of 15−120 min. It is found that the addition of TBAB not only shortens the induction time and accelerates the hydrate growth rate, but also enhances CO2 encaged into the hydrate. However, the number of total moles of gas consumed and the number of moles of CO2 transferred into the hydrate slurry phase decrease with the increase of the TBAB concentration when the TBAB concentration is above 0.29 mol %. The induction time reduces, and the number of moles of gas consumed, the hydrate formation rate, and the number of moles of CO2 encaged into hydrate phase increase with the increase of the driving force. However, when the driving force is more than 2.5 MPa, H2 prefers to go into the hydrate phase with the increase of the driving force, as compared to CO2. In addition, the temperature has little effect on the hydrate formation process.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100851u

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11602–11613

Titre :	Solvent recovery by steamless temperature swing carbon adsorption processes
Type de document :	texte imprimé
Auteurs :	Pradeep K. Sharma, Auteur ; Phillip C. Wankat, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11602–11613
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Solvent Adsorption Processes
Résumé :	Adsorption with activated carbon followed by regeneration with steam is the most common technique for solvent recovery from gas streams. The resulting steam−solvent gaseous mixture when condensed can result in either two separate layers (immiscible) or a single liquid phase (miscible or miscible with an azeotrope). For miscible systems that form azeotropes, the downstream distillation system can easily be more expensive than the adsorbers. An alternative is to use hot nitrogen instead of steam for desorption. By adding a short oxygen/water removal step to the adsorption cycle, the need for distillation is avoided. The model system studied for the azeotropic case was recovery of 0.5 mol % isopropanol (IPA) from air with hot nitrogen for regeneration. Since the nitrogen cost dominates, nitrogen should be recovered and recycled as much as possible. Two- and four-bed adsorption schemes were studied, and the four-bed system, which recovers almost all of the nitrogen, was best. A preliminary total cost comparison showed that solvent recovery of IPA with steam regeneration has total costs that are 14% higher than for IPA recovery with hot nitrogen regeneration if the nitrogen is recovered and recycled.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1008019

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11594–11601

Titre :	Physicochemical characteristics of hollow fiber structured packings in isopropanol / water distillation
Type de document :	texte imprimé
Auteurs :	Zhihong Yang, Auteur ; Guoliang Zhang, Auteur ; Feini Liu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11594–11601
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Fiber Water Distillation
Résumé :	Three kinds of hollow fiber membrane contactors, polyether sulfone (PES), polysulfone (PS), and polypropylene (PP), were applied in IPA/water distillation to check how the material and structure of membranes would affect the performance. The Hansen solubility parameter (HSP) was calculated to analyze the compatibility between polymers and IPA in operation. It was found that a hydrophobic asymmetric microporous membrane coating thin dense layer on the liquid side with good compatibility worked better in the process, while the membrane with interconnected porous morphology was more favorable for decreasing Rm and more sensitive to vapor load, which might worsen operation stability. Even a slight wetting (<20%) of membrane could result in a sharp decrease as high as 70% of the mass transfer across membrane. As before, all self-made modules in distillation could easily operate at a vapor velocity 5−6 times higher than the flooding limits for conventional packings and achieved an attractive low value of the height of transfer umit (HTU) less than 0.1 m, in which PES hollow fibers performed with excellent stability and gained the highest mass transfer coefficient KL in the experiment.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100437e

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11587-11593

Titre :	Experimental and theoretical studies of VOC adsorption on acid - activated bentonite in a fixed - bed adsorber
Type de document :	texte imprimé
Auteurs :	Abdelfattah Amari, Auteur ; Mohamed Chlendi, Auteur ; Abdelaziz Gannouni, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11587-11593
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Adsorber Fixed bedAdsorption Volatile organic compound
Résumé :	In this work, the adsorption of toluene onto acid-activated bentonite in a fixed bed using an inverse gas chromatography was investigated. Adsorbent was prepared according to an optimized activation process. Experimental and theoretical studies were established to evaluate the removal efficiency of toluene by adsorption on acid-activated bentonite and to predict kinetics parameters. A suitable adsorption model has been developed to simulate the measured data based on linear driving force approximation. The fourth-order Runge—Kutta method was used to integrate the partial differential equations, and the resulting functions were simultaneously solved to obtain the breakthrough profiles. Theoretical predictions from the model were compared with column adsorption data to ensure the validity of the model. Adequate agreement between simulations and experimental data was reached.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437857

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11582-11586

Titre :	Reduction of gold ions to gold particles by reusable soluble poly (tyramine) polymerized by horseradish peroxidase
Type de document :	texte imprimé
Auteurs :	Hidetaka Kawakita, Auteur ; Yuko Yoshimura, Auteur ; Keisuke Ohto, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11582-11586
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Gold Ions
Résumé :	A novel recovery method is proposed for gold ions using poly(tyramine), which is reductive and has easily manipulated solubility. Tyramine, which has phenol and amino groups, was polymerized using horseradish peroxidase. When the HCl concentration in solution was increased, poly(tyramine) solubility decreased, probably due to chloride ion coordination with the poly(tyramine) amino group. Poly(tyramine) was highly soluble at pH <4.0 in the pH region. When the polymer was reacted with gold ion solution in HCl for 48 h, the maximum amount of gold ions obtained was 4.0 mol/kg in a two-step reduction isotherm curve. Filtered reduced gold particles with poly(tyramine) were immersed in 0.1 M HCl solution, resulting in dissolution of the poly(tyramine), and the gold particles were then easily recovered by filtration. Adjusting the pH of the filtered solution to 7.5 allowed recovery of the poly(tyramine) as a precipitate, which could then be reused to reduce further gold ions.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100127g

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11572-11581

Titre :	Step response identification under inherent - type load disturbance with application to injection Molding
Type de document :	texte imprimé
Auteurs :	Tao Liu, Auteur ; Feng Zhou, Auteur ; Yi Yang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11572-11581
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Injection molding
Résumé :	Motivated by autotuning of injection velocity in an industrial injection molding machine, a step response identification method is proposed for practical application subject to inherent-type load disturbance. Both models of the process and the inherent-type load disturbance can be simultaneously derived from a step test. Identification algorithms are detailed for obtaining the widely used low-order models of first-order plus dead time (FOPDT) and second-order plus dead time (SOPDT). Based on the identified process and disturbance models, a two-degree-of-freedom (2DOF) internal model control (IMC) structure plus feed-forward control is proposed for improving load disturbance rejection. Analytical controller design formulas and tuning guidelines are developed accordingly. A practical application to the velocity control of an injection molding machine is shown to illustrate the effectiveness and merits of the proposed identification method and control strategy.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437855

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11564-11571

Titre :	Heuristic design of reaction / separation processes
Type de document :	texte imprimé
Auteurs :	William L. Luyben, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11564-11571
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Separation process Design
Résumé :	The dominant trade-off in chemical process design is between reactor size and recycle flow rate. Big reactors require larger capital investments in vessels and catalyst, but they result in smaller recycle flow rates for a given yield, which means lower capital investments and energy costs in the separation section of the process. Small reactors have reverse effects. Therefore, an economic optimum exists that balances the costs of the reaction section and the separation section of the process. This paper presents a heuristic approach to quickly determine this optimum trade-off during preliminary conceptual design. The basic idea is to start with a very large reactor and find the recycle flow rate required to meet some specified conversion/yield/selectivity criterion. This is the minimum recycle flow rate. Then a heuristic similar to that used in distillation column design is employed. The actual recycle flow rate is set equal to 1.2 times the minimum, and the reactor and separation sections are designed with this recycle. The heuristic recycle ratio has some dependence on the phase equilibrium (decreases as relative volatility decreases) and catalyst cost (increases as catalyst cost increases). The process studied has a continuous stirred-tank reactor, two distillation columns, and one recycle stream. Two consecutive reactions (A + B → C and A + C → D) produce a desired product C and an undesired product D. Achieving high selectivity requires low concentrations of A and C, so there is a large recycle of mostly B. Relative volatilities are assumed to be αA > αB >αC > αD, so there is one recycle from the overhead of the first distillation column containing unreacted A and B. The second column separates C and D. A second process is also studied involving an actual chemical system.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437854

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11557–11563

Titre :	Modified problem table algorithm for energy targeting
Type de document :	texte imprimé
Auteurs :	Santanu Bandyopadhyay, Auteur ; Gopal Chandra Sahu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11557–11563
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Energy
Résumé :	A simple modification of the original problem table algorithm (PTA) to target the minimum utility requirements in a heat exchanger network is proposed in this paper. The modified problem table algorithm (MPTA) eliminates the requirement of identification of streams to determine the net heat capacity flow rate at each temperature interval. Targeted utility requirements and the grand composite curve for the heat exchanger network problem are identical for both the original PTA and the proposed MPTA. This simple but fundamental change in the proposed MPTA, enhances its applicability to target the minimum external utility requirements in some special cases of heat-integrated water allocation networks. Pedagogical importance of the proposed MPTA is also discussed.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101472h

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11547–11556

Titre :	Operating parameters and selectivity in batch reactive distillation
Type de document :	texte imprimé
Auteurs :	Wei Qi, Auteur ; Michael F. Malone, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11547–11556
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Reactive distillation
Résumé :	This Article provides new predictions for selectivity in batch reactive distillation, identifying the reflux or reboil ratio and a Damköhler number (Da) as the key operating parameters. The dimensionless Da incorporates the influence of liquid holdup, vapor rate, and rate of reaction. Example results for a system of serial isomerization reactions and for the synthesis of ethylene glycol are provided. The results show that selectivity improvements in BRD are limited for high values of Da or for high values of the reflux or reboil ratio and that selectivity is enhanced as Da or reflux or reboil ratio is decreased. However, decreasing Da can cause conversion loss, which can be mitigated by increasing the reflux (or reboil) ratio at the expense of selectivity. Consequently, there is an optimum value of reflux or reboil ratio that gives a maximum yield for systems operated at low or moderate Da. For the isomerization in a BRD, the heat released by reaction can improve selectivity at the expense of conversion. For ethylene glycol synthesis at a low reboil ratio, BRD has a negative impact on both conversion and selectivity by causing separation of the reactants. We also show that decreasing the reboil ratio near the end of the BRD can increase the removal rate of EG and thereby improve selectivity. This operating strategy is different from a common operating strategy in distillation of increasing reboil ratio near the end of a batch or cut. We also find that an operation with a constant volumetric liquid flow rate provides lower selectivity than a constant molar liquid flow rate.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101417m

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11530-11546

Titre :	Development of self - validating soft sensors using fast moving window partial least squares
Type de document :	texte imprimé
Auteurs :	Jialin Liu, Auteur ; Ding-Sou Chen, Auteur ; Jui-Fu Shen, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11530-11546
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Software sensor Partial least squares
Résumé :	In the development of soft sensors for an industrial process, the colinearity of the predictor variables and the time-varying nature of the process need to be addressed. In many industrial applications, the partial least-squares (PLS) has been proven to capture the linear relationship between input and output variables for a local operating region; therefore, the PLS model needs to be adapted to accommodate the time-varying nature of the process. In this paper, a fast moving window algorithm is derived to update the PLS model. The proposed approach adapted the parameters of the inferential model with the dissimilarities between the new and oldest data and incorporated them into the kernel algorithm for the PLS. The computational loading of the model adaptation was therefore independent of the window size. In addition, the prediction performance of the model is only dependent on the retained latent variables (LVs) and the window size that can be predetermined from the historical data. Since a moving window approach is sensitive to outliers, the confidence intervals for the primary variables were created based on the prediction uncertainty. The inferential model would not be misled by the outliers from the online analyzers, whereas the model could be updated during the transition stage. The prediction performance of a soft sensor is not only dependent on the capability of the inferential model, but also relies on the data quality of the input measurements. In this paper, the input sensors were validated before performing a prediction. The deterioration of the prediction performance due to the failed sensors was removed by the reconstruction approach. A simulated example of a continuous stirred tank reactor (CSTR) with feedback control systems illustrated that the process characteristics captured by the PLS could be adapted to accommodate a nonlinear process. An industrial example, predicting oxygen concentrations in the air separation process, demonstrated the effectiveness of the proposed approach for the process industry.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437851

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11517-11529

Titre :	Determination of catalyst loading and shortcut design for binary reactive distillation
Type de document :	texte imprimé
Auteurs :	Jian Kai Cheng, Auteur ; Jeffrey D. Ward, Auteur ; Yu, Cheng-Ching, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11517-11529
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Distillation with reaction Design Loading Catalyst
Résumé :	Determination of the catalyst mass is a challenging problem in the conceptual design of reactive distillation systems. In this work, we use the concept of countercurrent cascaded vapor-liquid reactors (CCRs) to develop a shortcut method for the design of binary reactive distillation columns. An analytical expression for the theoretical minimum catalyst loading can be derived as the number of CCRs approaches infinity. On the basis of this theoretical catalyst loading, we present a calculation procedure to obtain the catalyst mass and other basic process parameters, for example, number of reactive stages and number of separation stages, without a detailed model. Three real binary systems are used to illustrate this shortcut method, and the results show that the estimated shortcut designs are similar to the optimal designs.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437850

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11506-11516

Titre :	Energy integration and analysis of solid oxide fuel cell based microcombined heat and power systems and other renewable systems using biomass waste derived syngas
Type de document :	texte imprimé
Auteurs :	Jhuma Sadhukhan, Auteur ; Yingru Zhao, Auteur ; Matthew Leach, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11506-11516
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Synthesis gas Biomass Solid oxide fuel cell
Résumé :	The objective of this paper was to design energy integrated solid oxide fuel cell (SOFC) based microcombined heat and power (micro-CHP) systems using syngas derived from lignocellulosic biomass waste. The novel contributions of this work include (1) integration of syngas between a community-scale biomass gasification plant and SOFC-based micro-CHP systems in buildings; (2) heat integrated designs of SOFC-based micro-CHP systems; and (3) integration between SOFC and other heat-led renewable technologies, such as, syngas boilers, ground source heat pump (GSHP), and air source heat pump (ASHP). Conceptual process design frameworks including detailed heat recovery strategies were developed using Aspen plus. It is demonstrated that increases in heat integration between the SOFC inlet and outlet gases enhance the power-to-heat generation ratio from the SOFC, albeit at a higher cost of heat exchanger area. A straw (14.6 MJ/kg LHV) based community-scale gasification plant can generate 50-100 kWe of electricity at an overall CHP generation efficiency of ∼42%, while if integrated to SOFC-based micro-CHP systems (I kWe) in individual dwellings via syngas, the overall energy efficiency can be greatly enhanced to ∼85%. It is envisaged that the SOFC should be operated at the highest electrical efficiency based on optimal heat integration; however, this needs to be coupled to other heat-led renewable technologies in order to meet the high residential heat to power demand ratio in the UK. Around 2.2 times more syngas may be required in boilers for supplementing residential heating. In integration with a GSHP loop, the flue gas from SOFC can itself be used as a refrigerant, and energy integration between the two systems can achieve an overall efficiency of ∼90%.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437849

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11491–11505

Titre :	Optimal Scheduling of Pipeline Systems with a Resource−Task Network Continuous-Time Formulation
Type de document :	texte imprimé
Auteurs :	Pedro M. Castro, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11491–11505
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Pipeline systems
Résumé :	This work addresses the short-term scheduling problem involved in the pipeline transportation of refined petroleum products to distribution centers serving local markets. A new continuous-time formulation is proposed that can handle complex treelike systems involving multiple refineries and depots. The novelty concerns the modeling of the complex storage policy associated with the flow of multiple products inside the pipeline. This is accomplished through the use of real and accumulated volume resources for every product, coupled with filling, moving, and emptying tasks, under the scope of the resource−task network process representation. Computational studies are performed to compare the performance of the new approach to three models from the literature that rely on the concept of batches rather than events to model what is in reality a continuous system. The results show that the proposed approach is wider in scope with the typical drawback of being less efficient for structural subclasses of the general problem.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1010993

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11482–11490

Titre :	Design of a robust nonlinear model predictive controller based on a hybrid model and comparison to other approaches
Type de document :	texte imprimé
Auteurs :	Rosendo Diaz-Mendoza, Auteur ; Hector Budman, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11482–11490
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hybrid Robust Nonlinear
Résumé :	A methodology to systematically design a model-based nonlinear model predictive controller is presented. The controller is referred to as hybrid since it uses the first-principles model to calculate the value of the controlled variables along the prediction and control horizons whereas uses the empirical model to ensure a terminal condition that accounts for model errors. The empirical Volterra series model was split into nominal and uncertain parts that were then used to formulate a structured singular value based robustness test. The proposed hybrid controller was compared against a robust empirical that uses solely an empirical model and to a nonrobust first principles model based nonlinear model predictive controller. To show the benefits of considering robustness in the controller formulation, extensive simulation studies were conducted that considered mismatch between the real process parameters and the model parameters. It is shown that in some case the performance of the hybrid controller can be superior to the purely empirical and to the first principles based controllers.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1016283

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11471-11481

Titre :	Smith predictor - based control schemes for dead - time unstable cascade processes
Type de document :	texte imprimé
Auteurs :	Pedro Garcia, Auteur ; Tito Santos, Auteur ; Julio E. Normey-Rico, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11471-11481
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Cascade processes.
Résumé :	This paper presents two simple and efficient Smith predictor (SP) based control schemes which can be used to control open-loop stable or unstable time-delay cascade processes. The proposed structures have two control loops, a secondary inner loop and a primary outer loop. Similar to previous approaches, the secondary loop uses an internal model control (IMC) structure. Two different schemes are proposed for the outer loop that has an unstable open-loop behavior. Contrary to previous proposed controllers, where a delayed model should be used in the stabilization and tuning procedure by considering some kind of polynomial approximation of the dead time, in the proposed structures, internal stability is naturally achieved through a suitable implementation and tuning of the controller without using any delay approximation. To illustrate this, simulation comparative results with some of the schemes recently presented in the literature are presented, showing the simplicity of the proposed design. Moreover, the simulations show that the proposed schemes allow one to obtain some improvement in disturbance rejections performance.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1009958

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11464–11470

Titre :	Effect of internal structure on flue gas mesulfurization with rapidly hydrated sorbent in a circulating fluidized bed at moderate temperatures
Type de document :	texte imprimé
Auteurs :	Jie Zhang, Auteur ; Changfu You, Auteur ; Changhe Chen, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11464–11470
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Gas desulfurization Sorbent
Résumé :	A moderate-temperature desulfurization process at 600−800 °C was studied in a pilot-scale circulating fluidized bed flue gas desulfurization (CFB-FGD) experimental facility with the addition of the internal structure. The rapidly hydrated sorbent and the desulfurization products were analyzed to clarify the influence mechanism of the internal structure on the moderate-temperature desulfurization process. The results show that the desulfurization efficiency with the internal structure at 600−800 °C was 74−93% for the calcium to sulfur (Ca/S) molar ratio of 2.0, which was higher than the desulfurization efficiency without the internal structure of 67−83%. As for the calcium-containing compositions, the desulfurization products included about 70% cyclone recirculation sample and about 30% bag filter sample. The cyclone recirculation sample was mainly composed of CaSO4 and CaO. The bag filter sample not only contained high contents of CaSO4 and CaO but also contained a considerable amount of CaCO3 and even some unreacted Ca(OH)2. With the addition of the internal structure, the calcium conversion rate of the cyclone recirculation sample greatly increased from 42.8 to 47.4% while that of the bag filter sample just increased from 29.4 to 30.7%. It demonstrated that the main contributor for the improved desulfurization efficiency was the cyclone recirculation sample due to the improved solids concentration distribution and the enhanced gas−solid contact efficiency. The calcium conversion rate for the bag filter sample depended on the solids concentration distribution as well as the particle residence time in the moderate temperature range, which indicated that prolonging the particle residence time for the fresh sorbent and the fall off calcium-containing particles was important to further improve the desulfurization performance. These results provided good guidance for realizing high desulfurization efficiency and low flow resistance in dry FGD processes.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100988r

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11453-11463

Titre :	Simultaneous cyclic scheduling and control of tubular reactors : single production lines
Type de document :	texte imprimé
Auteurs :	Antonio Flores-Tlacuahuac, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11453-11463
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Production Tubular reactor Scheduling
Résumé :	In this work, we propose a simultaneous scheduling and control optimization formulation to address both optimal steady-state production and dynamic product transitions in continuous multiproduct tubular reactors. The simultaneous scheduling and control problem for continuous multiproduct tubular reactors is cast as a Mixed-Integer Dynamic Optimization (MIDO) problem. The dynamic behavior of the tubular reactor is represented by a set of nonlinear partial differential equations that are merged with the set of algebraic equations representing the optimal schedule production model. By using the method of lines, the process dynamic behavior is approximated by a set of nonlinear ordinary differential equations. Moreover, time discretization of the underlying system allows us to transform the problem into a Mixed-Integer Nonlinear Programming (MINLP) problem. Three multiproduct continuous tubular reactors are used as examples for testing the simultaneous scheduling and control optimization formulation.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437844

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11443–11452

Titre :	Design of nonlinear unknown input observer for process fault detection
Type de document :	texte imprimé
Auteurs :	Jafar Zarei, Auteur ; Javad Poshtan, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11443–11452
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Nonlinear dynamic system
Résumé :	The objective of this paper is to design a robust fault detection scheme for nonlinear systems. A novel procedure for the design of a nonlinear unknown input observer (UIO) is proposed. The basic principle of unknown input observers is to decouple disturbances from the state estimation error. In the proposed method, the linear UIO design algorithm is extended to nonlinear systems and then observer gain is obtained using unscented transformation (UT). To illustrate the efficiency of the proposed method, it is adopted to detect sensor faults of a highly nonlinear dynamic system. The faulty behavior of output sensors in a jacketed continuous stirred tank reactor (CSTR) is investigated. A single full-order observer is designed to detect sensor faults in the presence of unknown inputs (disturbances). Simulation results show that disturbances and, therefore, a certain degree of model uncertainties can be distinguished from a response to a sensor fault.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100477m

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11434-11442

Titre :	Recursive least squares - based adaptive control of a biodiesel transesterification reactor
Type de document :	texte imprimé
Auteurs :	Ho Yong Kuen, Auteur ; Farouq S. Mjalli, Auteur ; Yeoh Hak Koon, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11434-11442
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Reactor Transesterification Adaptive control
Résumé :	Proper control of biodiesel reactors poses a number of challenges. These arise from the presence of multiple chemical reactions, the complex heat and mass transfer characteristics, and the highly nonlinear dynamics. In this work, a new adaptive control scheme was implemented to automatically tune the controller on the basis of the most recent updated process dynamics. This scheme demonstrates the powerful integration of an online process modeling tool (recursive least squares, RLS) into a renowned and yet simple model-based controller design method (internal model control, IMC). Two adaptive control loops were designed, in which the sampling time of the RLS algorithm and the IMC closed loop time constant were determined by constrained optimization with the genetic algorithm. Comparison with conventional PID controllers revealed the superiority of the new adaptive control scheme in set point tracking. Good disturbance rejection properties were also demonstrated by the new adaptive control scheme. The results attained in this work demonstrate that a good adaptive control scheme can be implemented for the biodiesel transesterification reactors with minimal knowledge about the process model.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437842

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11421–11433

Titre :	Design and maintenance of multichannel protective systems
Type de document :	texte imprimé
Auteurs :	Yue-Cheng Liao, Auteur ; Chuei-Tin Chang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11421–11433
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Multichannel protective systems
Résumé :	To mitigate the undesirable effects caused by accidents in chemical plants, it is a common practice to install protective systems on processing units operated under hazardous conditions. Because hardware failures are basically random events, the availability of the protective system is highly dependent on its structural properties and also the maintenance programs. The aim of this study is to improve and generalize the current practice(1) for generating the design specifications and maintenance policies. Specifically, instead of monitoring only a single condition, in this work, the emergency system status is detected according to the measurements of several different process variables (or “alarm channels”) so as to optimize alarm performance. Because each of these channels can be consist of more than one online sensor, a modified version of the spare-supported corrective maintenance policy is also devised in this study to enhance availability. By solving the corresponding mathematical programming model, the optimal configurations of sensors and shutdown units, the best corrective and preventive maintenance procedures, and alarm/shutdown logic can all be identified automatically. Two examples are provided in this article to demonstrate the feasibility and effectiveness of the proposed approach.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie901818e

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11415-11420

Titre :	Cyclic voltammetric preparation of palladium nanoparticles for ethanol oxidation reaction
Type de document :	texte imprimé
Auteurs :	Keqiang Ding, Auteur ; Guokai Yang, Auteur ; Suying Wei, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11415-11420
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Oxidation Nanoparticle Preparation
Résumé :	By simple cyclic voltammetry of a PdO-coated glassy carbon (GC) electrode for a few cycles with the potential swept from -1.0 to -1.2 V versus saturated calomel electrode in an alkaline solution containing ethanol, a Pd particle modified GC electrode was fabricated. It showed satisfactory catalysis toward the ethanol oxidation reaction.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437840

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11408-11414

Titre :	Poly (ethyleneimine) - loaded silica monolith with a hierarchical pore structure for H2S adsorptive removal
Type de document :	texte imprimé
Auteurs :	Qingjun Chen, Auteur ; Feichao Fan, Auteur ; Donghui Long, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11408-11414
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydrogen sulfides Pore structure Monolithic construction
Résumé :	Poly(ethyleneimine) (PEI) loaded hierarchical porous silica monolith has been developed as a recycle H2S sorbent at low temperature. The sorbent was characterized by N2 adsorption, scanning electron microscope, transmission electron microscope, Fourier transform infrared spectra, and activity tests. The effects of the amount of PEI loading, the operating temperature, and the PEI polymerization degree on H2S removal were studied. The sorbent demonstrated a large H2S breakthrough capacity of 1.27 mmol of H2S/(g of sorbent) at 22 °C, which is about 60% larger than that of PEI-loaded SBA-15 or MCM-41 sorbent. The optimal PEI loading is 65 wt %, and the most ideal PEI molecular weight is 600. As the decrease of the temperature, the sorption performance of the sorbent increases greatly. There are two important factors affecting the performance of H2S sorption: the amount of available PEI in the sorbent and the interaction between H2S and amine functional groups of PEI. In addition, the developed sorbent can be regenerated easily at 75 °C, and it exhibits excellent regenerability and stability. These results indicate that PEI-loaded hierarchical porous silica sorbent will be promising for removing H2S in the future.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437839

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11402–11407

Titre :	Debonding performance of various cationic surfactants on networks made of bleached kraft fibers
Type de document :	texte imprimé
Auteurs :	Pedram Fatehi, Auteur ; Kevin C. Outhouse, Auteur ; Huining Xiao, Auteur
Année de publication :	2011
Article en page(s) :	pp.11402–11407
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Cationic Fibers
Résumé :	Debonding agents are applied in the paper industry for various purposes, for example, to increase the softness of tissue paper. In this work, the debonding capacities of three cationic aliphatic ammonium surfactants and one alkoxylated amine surfactant on kraft fibers were determined. The results showed that the adsorption of the alkoxylated amine surfactant (AAS) was higher than that of others on the fibers, but a cationic cetyltrimethyl ammonium surfactant (cetyltrimethyl ammonium bromide, CAB) was the most effective debonding agent, probably because of its relatively long hydrophobic chain. By applying CAB at levels of up to 20 mg/g, the tensile and burst indices were reduced by 37% and 41%, respectively. By applying AAS at levels of up to 20 mg/g, the tensile and burst indices of the networks were reduced by 18.6%, and 14.2%, respectively. The tear index of the fiber networks negligibly changed upon application of AAS, but increased by 19% upon application of CAB. The strain of the fiber networks prior to rupturing increased upon application of AAS, whereas it decreased upon application of CAB, which implies that the surfactants have different debonding mechanisms. The debonding efficiency of CAB was independent of both the refining revolutions and basis weights of the fiber networks.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101442p

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11393–11401

Titre :	Prediction and evaluation of styrenic block copolymers as surface modifiers for multiwalled carbon nanotubes in a - terpineol - based pastes
Type de document :	texte imprimé
Auteurs :	Sung Chul Hong, Auteur ; Jeong Eun Shin, Auteur ; Hee Jung Choi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11393–11401
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Copolymers Nanotubes
Résumé :	A well-defined styrenic block copolymer was prepared through controlled/“living” radical polymerization technique and evaluated as a polymeric surface modifier for multiwalled carbon nanotube (MWCNT) in α-terpineol-based paste. First, poly(maleic anhydride-co-p-acetoxystyrene)-block-poly(p-acetoxystyrene) copolymer was prepared through a nitroxide-mediated polymerization (NMP) technique in an efficient “one-pot” reaction. The copolymer was then functionalized with pyrene through an imidization reaction (SPM). Finally, p-acetoxystyrene units were converted to p-hydroxystyrene units through hydrolysis, affording pyrene-functionalized poly(maleic acid-co-p-hydroxystyrene)-block-poly(p-hydroxystyrene) (HSPM). Pyrene units in one block afforded efficient attachment points to the surface of MWCNT through π−π interaction, while poly(p-hydroxystyrene) or poly(p-acetoxystyrene) tails afforded enhanced affinities with α-terpineol, as predicted by Hansen solubility parameter theory. Fabrications of electrodes through screen printing procedures employing MWCNT/HSPM or MWCNT/SPM pastes were facilitated through the surface modification of MWCNTs with the block copolymers, as evidenced by low viscosity, more homogeneous and smooth pastes, homogeneous/uniform MWCNT coatings, and low sheet resistance of the electrode.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1013822

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp 11385–11392

Titre :	Electrochemical deposition of Co - Sb thin films and nanowires
Type de document :	texte imprimé
Auteurs :	Dat V. Quach, Auteur ; Ruxandra Vidu, Auteur ; Joanna R. Groza, Auteur
Année de publication :	2011
Article en page(s) :	pp 11385–11392
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Electrochemical Nanowires
Résumé :	Co−Sb thin films and nanowires were grown on gold-coated polymer templates by electrochemical deposition under different potentiostatic conditions from −0.8 to −1.0 V vs Ag/AgCl. The growth of nanowires was 3D and went through several growth stages starting from the gold-coated wall. Overgrowth of nanowires out of the porous template did not produce a fully dense film; instead, Sb-rich columnar structures (mushroom caps) were developed and connected by Co-rich needle-like structures. Compared to nanowires, the mushroom caps had a lower content of Co. With a more negative deposition potential, the content of Co in the nanowires and the mushroom caps increased. A composition of Co:Sb = 1:3 in nanowires was obtained at a constant deposition potential of −0.965 V.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101173u

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11380-11384

Titre :	Primarily Industrialized Trial of Novel Fibers Spun from Cellulose Dope in NaOH/Urea Aqueous Solution
Type de document :	texte imprimé
Auteurs :	Ran Li, Auteur ; Chunyu Chang, Auteur ; Jinping Zhou, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11380-11384
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Aqueous solution
Résumé :	Faced with the serious pollution caused by the viscose method (use of CS2), a primarily industrialized trial via a "green" wet-spinning process based on dissolution of cellulose in NaOH/urea aqueous solution precooled to -12.5 °C was performed. In a dissolution tank of 1000 L capacity, the cellulose could be dissolved completely in the NaOH/urea system within 5 min, and cellulose fibers were spun successfully from the transparent dope. A 15:10 H2SO4/Na2SO4 aqueous solution was adopted as the first coagulants in the bath, and a 5 wt % H2SO4 aqueous solution was used as the second coagulant to fabricate new regenerated cellulose fibers. There was no evaporation of any chemical agent during dissolution and regeneration. The structure of the fibers was characterized with scanning electron microscope, wide-angle X-ray diffraction, 13C NMR, and tensile testing. The cellulose fibers exhibited a bright surface and a circular section, and their tensile strength reached 1.63-1.97 cN/dtex, which is close to commercial viscose fiber, although the drawing orientation in the production process was not performed. Therefore, we created a novel and simple approach combining a nonpolluting, low-cost, and quick process for the production of cellulose fibers, which was important for environmental conservation.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437835

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11369-11379

Titre :	Dissipative particle dynamics and flory − huggins theories for predicting the rheological behavior of ultrahigh molecular weight polyethylene blends
Type de document :	texte imprimé
Auteurs :	Jing-Gang Gai, Auteur ; Guo-Hua Hu, Auteur ; Hui-Lin Li, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11369-11379
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Prediction
Résumé :	This work aims to experimentally and theoretically study the effects of normal molecular weight polymers (NMWP) such as high-density polyethylene, low-density polyethylene, and polypropylene as processing aids on the morphology and rheological behavior of ultrahigh molecular weight polyethylene (UHMWPE). As is shown by scanning electron microscope observations, rheological measurements, and dissipative particle dynamics simulations, formation of a lubricating phase between the UHMWPE particles is responsible for the viscosity reduction of the UHMWPE. Besides, phase diagram studies on the UHMWPE/NMWP blend suggest that the optimum composition ratio of the blends lies in their composition-sensitive region when the parameter χ and molecular weight of each component are fixed at low shear rates. Meanwhile, the optimum range of parameter χ is above but close to the corresponding binodal curve at high shear rates.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437834

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11363-11368

Titre :	Effect of graphite and carbon nanofiber additives on the performance efficiency of a gear pump driven hydraulic circuit using ethanol
Type de document :	texte imprimé
Auteurs :	Philip Martorana, Auteur ; Ilker S. Bayer, Auteur ; Adam Steele, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11363-11368
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Pump Additive
Résumé :	We show that fine graphite flake and carbon nanofiber dispersed ethanol solutions can potentially replace conventional hydraulic fluids in gear pump-driven hydraulic circuits operating below I MPa gauge pressure. Low-viscosity hydraulic fluids are generally detrimental to pump life. However, both graphite and carbon nanofiber dispersions in ethanol within a concentration range of 195-1500 ppm can sustain hydraulic circuits with increases in pump efficiency and without modifying the viscosity of ethanol. Pump inlet pressure, volumetric flow rate, and electric power consumption data were recorded over a range of pump discharge pressures. Pump power consumption at a given differential pump pressure was found to remain approximately constant for all suspensions. However, increases in both volumetric flow rate and overall pump efficiency were observed when pure ethanol was replaced by the nanostructured carbon/ethanol solutions. The presence of the additives can partially or collectively improve a number of lubrication mechanisms which exist in a gear pump such as boundary, hydrodynamic, hydrostatic, elastohydrodynamic, and mixed-film lubrication. Additionally, we observed that the additives deposited permanently on gear and enclosure surfaces creating low shear strength films which can help reduce friction. Qualitative examination of environmental scanning electron microscope images of colloidal graphite and carbon nanofiber additive morphology before and after extended run periods indicated that graphite retained significant resilience, whereas carbon nanofibers appear to have undergone some scission.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437833

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11357-11362

Titre :	Development of green composites from furfuryl palmitate
Type de document :	texte imprimé
Auteurs :	Ershad Mistri, Auteur ; N. R. Bandyopadhyay, Auteur ; Santi Nath Ghosh, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11357-11362
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Composite material
Résumé :	Renewable materials like furfuryl alcohol, palmitic acid, and jute were used for the first time to develop green biocomposites. Furfuryl ester of palmitic acid was prepared by enzymatic route and was used as the matrix material for developing green composite materials. The Diels-Alder reaction was carried out between furfuryl palmitate and maleic anhydride which resulted in a new material. Crystal growth was observed on Diels-Alder reaction along with a noncrystalline, semisolid part. The Diels-Alder product was characterized by nuclear magnetic resonance (NMR), IR, optical microscopy. Jute reinforced composites were prepared by solvent impregnation method followed by compression molding. The resulting composites were tested for their mechanical properties and the fiber/matrix bonding was investigated under SEM.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437832

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11351-11356

Titre :	Enhanced surface wetting of pigment coated paper by UVC irradiation
Type de document :	texte imprimé
Auteurs :	Anni Maattanen, Auteur ; Petri Ihalainen, Auteur ; Roger Bollstrom, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11351-11356
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Pigments Wetting
Résumé :	The effect of UVC (λmax = 254 nm) treatment on wettability of pigment-coated papers was examined. The paper samples were coated with conventional pigments including ground calcium carbonate (GCC), precipitated calcium carbonate aragonite (PCC), and Kaolin. The coating formulation also included poly(styrene-butadiene) (SB) latex binder and a dispersing agent, sodium polyacrylate (NaPA), for formation of a colloidally stable pigment slurry at a relatively high solids content. A significant decrease of contact angle of water on the studied pigment-coated papers was observed as a result of UVC treatment. The effect was most pronounced for carbonate-based coatings. In addition, the UVC treatment showed long-term stability. A detailed analysis of the surface chemical composition of the PCC-based coatings indicated that the UVC treatment leads to photooxidation and photodegradation, and eventual desorption of a thin NaPA overlayer from the pigment surface. This in turn increases the polarity of the surface and enhances its wettability.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437831

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11344-11350

Titre :	Crystallization of Calcium Sulfate Dihydrate in the Presence of Colloidal Silica
Type de document :	texte imprimé
Auteurs :	Fulin Wang, Auteur ; Thomas E. Davis, Auteur ; Volodymyr V. Tarabara, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11344-11350
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Crystallization
Résumé :	The effects of silica colloids on calcium sulfate dihydrate (gypsum, CaSO4·2H2O) crystallization are studied using feed solutions of varying degrees of supersaturation. A combination of light transmittance and electrical conductivity measurements is employed to characterize various aspects of the crystallization process. The induction time, nucleation rate, surface energy, and rate of crystallization of gypsum crystals are measured as functions of the saturation and the presence of noncrystallizing (SiO2) colloids. Scanning electron microscopy (SEM) imaging is used to characterize the morphology of formed crystals. The induction time and the rate of crystallization are both shown to increase when gypsum crystal formed from solutions containing suspended colloids. The findings are rationalized in terms of a mechanistic model that links the random motion of colloids with nucleation and crystal growth processes. The results have important implications for a variety of industrially relevant processes such as heat exchange and membrane separation and related fouling phenomena.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437830

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11331–11343

Titre :	Modeling of advanced oxidation of trace organic contaminants by hydrogen peroxide photolysis and fenton’s reaction
Type de document :	texte imprimé
Auteurs :	Mario R. Rojas, Auteur ; Fernando Perez, Auteur ; Daniel Whitley, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11331–11343
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydrogen Photolysis
Résumé :	The kinetics of nonylphenol and p-cresol destruction by hydrogen peroxide photolysis and Fenton’s reaction was investigated under a variety of operating conditions in homogeneous, laboratory-scale batch reactor experiments. Models with no adjustable parameters successfully accounted for radical initiation by photolysis of H2O2 or radical initiation by Fenton’s mechanism, reaction of organic targets with hydroxyl radical, and radical scavenging and recombination mechanisms, as well as changes in solution pH due to evolution of carbon dioxide because of target mineralization. Simulations of the UV/H2O2 and Fenton-based models can be used to anticipate the kinetics of advanced oxidation involving any target compound for which there is a known apparent second-order rate constant for reaction with hydroxyl radical. The presence of radical scavengers was successfully treated by the model, suggesting that the model can be generalized to the treatment of complex matrixes.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101592p

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11321-11330

Titre :	Adsorption and photocatalytic degradation of reactive brilliant red K - 2BP by TiO2/AC in bubbling fluidized bed photocatalytic reactor
Type de document :	texte imprimé
Auteurs :	Qijin Geng, Auteur ; Wenwen Cui, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11321-11330
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Photocatalysis Photochemical reactor Catalytic reactor Fluidized bed Fluidization Bubbling Titanium oxide Photochemical degradation Adsorption
Résumé :	An activated carbon-supported titanium dioxide photocatalyst (TiO2/AC) was prepared by a spinning coating method and applied in a designed bubbling fluidized bed photocatalytic reactor (BFBPR). Adsorption and photocatalytic degradation of reactive brilliant red K-2BP in BFBPR were investigated considering the pH value, Na2SO4 added, and initial dye concentration. The experimental results indicated that the adsorption and photocatalytic degradation efficiencies of K-2BP were influenced by the pH value, Na2SO4 added, and initial dye concentration. The adsorption and photocatalytic degradation of K-2BP was approximated to the maximum value at pH value 5.7. The complex influence of Na2SO4 added on photocatalytic degradation of K-2BP at alkaline suspension was observed and explained according to the adsorption models proposed and degradation mechanism of a new free radical (SO4•−) produced. In addition, the presence of Na2SO4 plays dual functions, i.e., salt bridge-role in adsorption for Na+ and competition adsorption between anion dye molecules and SO42−, conformed by adsorption models proposed and FT-IR spectra for dye adsorption on TiO2/AC. The mass-transfer limited and screening effect that resulted from variation of the initial dye concentration may be approximated to the minimum effect at concentration of 3.75 mg L−1, with the maximum degradation efficiency above 80%. The Langmuir−Hinshelwood kinetic model was applied to explore the adsorption and degradation. Finally, the special reaction paths were inferred with variation of experimental environments.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437828

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11310-11320

Titre :	Design and packaging of microreactors for high pressure and high temperature applications
Type de document :	texte imprimé
Auteurs :	Samuel Marre, Auteur ; Andrea Adamo, Auteur ; Soubir Basak, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11310-11320
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Microreactor Packaging Design
Résumé :	The development of chemically compatible microsystems that can operate across expanded process conditions, such as high pressures (HP) and high temperatures (HT), is of great interest for many applications, including high pressure chemistry and hydrothermal and supercritical fluid processes. We present a methodology for the successful design and use of HP/HT microsystems. Key parameters for the fabrication of microreactors and modular fluidic packaging able to withstand severe pressure and temperature conditions (30 MPa, 400 °C) are described. Applications of these HP/HT plug and play microsystems are illustrated with examples, including multiphase flow visualization through the transition of liquid-liquid immiscible hexane-water segmented flow to homogeneous supercritical flow, on chip supercritical water oxidation, and synthesis of iron oxide nanoparticles.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437827

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11302-11309

Titre :	Studies on the adsorption and kinetics of photodegradation of pharmaceutical compound, indomethacin using novel photocatalytic adsorbents (IPCAs)
Type de document :	texte imprimé
Auteurs :	Shaik Basha, Auteur ; David Keane, Auteur ; Anne Morrissey, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11302-11309
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Photocatalysis Photochemical degradation Kinetics Adsorption
Résumé :	Integrated photocatalytic adsorbents (IPCAs) based on TiO2-activated carbon synthesized by an ultrasonic impregnation technique have been used for the photodegradation of indomethacin (IND) in aqueous solutions. The IPCAs in dark adsorption studies had high affinity toward IND with the amount adsorbed proportional to the TiO2 loading. The adsorption capacity increased from 0.597 to 0.657 mmol/g with increase in TiO2 content from 0.5 to 10% in IPCAs. Three adsorption models, Langmuir, Freundlich and Sips, were used to describe the adsorption isotherms while the adsorption kinetic data were fitted to pseudofirst order and pseudosecond order models. The adsorption isotherm study showed that the adsorption followed both Sips and Langmuir models with high regression coefficients (R2) and low standard error (SE) and sum of residual square error (SSE) values. The adsorption kinetic data are well represented by pseudosecond order model. The kinetics of photocatalytic degradation under UV were found to follow a Langmuir-Hinshelwood model for the various IPCAs. The adsorption rate constant (Kads) was considerably higher than the photocatalytic rate constant (kL-H), suggesting that the photocatalysis of IND is the rate-determining step during the adsorption/ photocatalysis process. The proportion of TiO2 played a significant role upon the photoefficiency of the IPCAs. The photocatalytic efficiency of the 10% TiO2 IPCA remained greater than 70% after five cycles of use.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437826

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11294–11301

Titre :	Tar reduction by primary measures in an autothermal air - blown fluidized bed biomass gasifier
Type de document :	texte imprimé
Auteurs :	Manuel Campoy, Auteur ; Alberto Gomez-Barea, Auteur ; Diego Fuentes-Cano, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11294–11301
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Biomass Fluidized bed Fluidization
Résumé :	An experimental investigation in a 100 kWLh bubbling fluidized bed gasifier (FBG) was conducted to study the effect of primary measures on the tar composition in the gas. The measures tested included the variation of the stoichiometric ratio, SR, defined as the ratio of fed to stoichiometric air, secondary-air injection in the freeboard, and addition of lime and alumina to the reference bed material (ofite). The reactor was operated nearly adiabatic, with the aim of simulating the performance of industrial autothermal air-blown FBG units. An optimum value of SR was found at approximately 0.3, where the cold gasification efficiency was maximum (70%) and the tar concentration was reduced by a factor of 3 with respect to reference conditions. Addition of secondary air (keeping SR constant) reduced the gravimetric tar and the water-soluble tar compounds up to 20 and 30%, respectively; a fixed ratio of secondary to total air of I I% was investigated in this work for three valued of SR. The use of lime allowed for the reduction of the overall tar content up to 50%, whereas the decrease using alumina was rather low. None of the measures tested effectively reduced the heavy tar compounds, so the minimum value computed for the tar dew point was 170 °C.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437825

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11287-11293

Titre :	Dehydrogenation of methylcyclohexane to produce high - purity hydrogen using membrane reactors with amorphous silica membranes
Type de document :	texte imprimé
Auteurs :	Kazunori Oda, Auteur ; Kazuki Akamatsu, Auteur ; Takashi Sugawara, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11287-11293
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Membrane reactor High purity Dehydrogenation
Résumé :	We developed a membrane reactor that can produce high-purity hydrogen in one step from methylcyclohexane. This membrane reactor combined a hydrogen-selective amorphous silica membrane prepared with dimethoxy-diphenylsilane and oxygen and employing counter-diffusion chemical vapor deposition, and Pt/Al2O3 catalyst. The silica membrane showed excellent hydrogen permeance at 573 K of the order of 10-5 mol m-2 s-1Pa-1 and high hydrogen/sulfur hexafluoride permselectivity of around 104. The membrane reactor exhibited equilibrium shifts as expected under reaction temperatures ranging from 473 to 553 K and reaction pressures ranging from 0.1 to 0.25 MPa, and these performances were successfully predicted using a simulation model, which was also developed in this study. Finally, we demonstrated that hydrogen with purity as high as 99.95% was produced from methylcyclohexane in the membrane reactor without using carrier gas or sweep gas.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101210x

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11280–11286

Titre :	Effect of polymer size on heterogeneous catalytic polystyrene hydrogenation
Type de document :	texte imprimé
Auteurs :	Laura Beth Dong, Auteur ; Salomon Turgman-Cohen, Auteur ; George W. Roberts, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11280–11286
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydrogenation Catalytic reaction
Résumé :	The effect of polymer coil size on the rate of polystyrene (PS) hydrogenation was studied in a slurry reactor with mixtures of decahydronaphthalene (DHN) and carbon dioxide (CO2) as the solvent for the polymer. The PS coil size was changed by varying the polymer molecular weight from 9300 g/mol to 357 000 g/mol and by varying the CO2 concentration. Using a 5% Pd/5% Ru/SiO2 catalyst, the rate of aromatic ring hydrogenation at 150 °C was found to be strongly dependent on the size of a polymer coil relative to the average pore diameter of the catalyst. Significant pore diffusion limitations, as indicated by values of the Weisz modulus, were observed with increasing polymer molecular weight. Increasing the concentration of CO2 resulted in increased reaction rates, with an improvement of nearly 2 orders of magnitude at the highest PS molecular weight.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437823

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11269–11279

Titre :	Determination of the low - temperature water − gas shift reaction kinetics using a cu - based catalyst
Type de document :	texte imprimé
Auteurs :	Diogo Mendes, Auteur ; Vania Chibante, Auteur ; Adelio Mendes, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11269–11279
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Gas Kinetics
Résumé :	An integral packed-bed reactor was used to determine the kinetics of the water−gas shift (WGS) reaction over a CuO/ZnO/Al2O3 catalyst, under operating conditions such that there was no film or intraparticle resistance. Experiments were carried out over a wide range of temperatures and space times using a typical reformate gas mixture (4.70% CO, 34.78% H2O, 28.70% H2, 10.16% CO2, balance N2). In the first part of the work, three different mechanistic-rate equations and two empirical kinetic models are proposed to describe the WGS kinetic data throughout the entire range of temperatures. To improve the independence of the parameters in using the Arrhenius and van’t Hoff equations, the temperature was centered. Good agreement was obtained between the Langmuir−Hinshelwood (LH) rate equations and the experimental results. Further, analysis using two different temperature ranges for parameter estimation revealed distinct rate-controlling mechanisms for each range. For temperatures of 180−200 °C, the associative (LH) mechanism was predominant, whereas the redox pathway showed the best fit to the experimental reaction rates in the range of 230−300 °C. Finally, an isothermal plug-flow reactor model was used to simulate the packed-bed tubular reactor for the WGS reaction using the composed kinetics. The reactor model was assessed against the experimental CO outlet concentration, and satisfactory agreement was found between the model predictions and the experimental results.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101137b

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11260-11268

Titre :	Synergistic process for coker gas oil and heavy cycle oil conversion for maximum light production
Type de document :	texte imprimé
Auteurs :	Gang Wang, Auteur ; Ze-kun Li, Auteur ; He Huang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11260-11268
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Production Gas oil Synergism
Résumé :	Coker gas oil (CGO), heavy cycle oil (HCO), and a CGO-HCO blend were treated by solvent refinement and then cracked in a FCC pilot plant over a commercial Y zeolite-based catalyst at selected reaction conditions. The experimental setup simulates the cracking behavior of different feed streams in an FCC unit using different processing schemes. The processing alternative that can yield the highest conversion and maximum light oil production was evaluated. Blending unrefined CGO into FCC feedstock results in decreased feed conversion and retarded desirable product yields. This is attributed to the large amount of basic nitrogen compounds and polycyclic aromatics found in unrefined CGO. Solvent refinement of CGO, however, produced significant improvements in product yield, denitrification and contaminant-removal rates, and product quality. The same observations are true for feedstocks blended individually with refined HCO and a refined mixture of CGO and HCO. Refined oils are also superior to RFCC feedstocks for their improved feed conversion, product yield and product quality.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437821

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11254–11259

Titre :	Desulfurization of gasoline over nanoporous nickel - loaded Y - type zeolite at ambient conditions
Type de document :	texte imprimé
Auteurs :	Majid Dastanian, Auteur ; Fakhry Seyedeyn-Azad, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11254–11259
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Zeolite Desulfurization
Résumé :	Desulfurization of heavy straight-run gasoline (HSRG) was accomplished over Ni(II)-Y zeolite. Na—Y zeolite, a nanoporous adsorbent, was synthesized and ion-exchanged with NH4NO3 to obtain NH4-Y zeolite. The obtained material was then converted to H-Y zeolite by calcination. Ni—Y zeolite was prepared by solid-state ion exchange (SSIE) of H-Y zeolite using Ni(NO3)2·6H2O. The breakthrough curve for desulfurization of HSRG containing about 140 ppmw of sulfur compounds was obtained in a batch reactor at ambient conditions. The effects of temperature, Ni content in the zeolite framework, and aging of the zeolite on the desulfurization process were investigated. Ni-Y zeolite exhibited a high capability for the desulfurization of gasoline at ambient conditions.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437820

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11250–11253

Titre :	Effect of reactive distillation on the yield of tetraacetylethylenediamine (TAED)
Type de document :	texte imprimé
Auteurs :	Eun-Seon Kim, Auteur ; Kyun Young Park, Auteur ; Jung-Moo Heo, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11250–11253
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Tetraacetylethylenediamine
Résumé :	Tetraacetylethylenediamine (TAED) was prepared by acetylation of diacetylethylenediamine (DAED) with acetic anhydride in a 5 L reactor coupled with a packed distillation column, 2.5 cm in inside diameter and 1 m in length. The reaction temperature was set at 135 °C and the reflux ratio at 6. The molar ratio of acetic anhydride to DAED was varied from 3 to 5. A TAED yield as high as 80% was obtained, higher by 15% than in the absence of distillation. The temporal variation of the TAED yield was calculated using the kinetic parameters in the literature. Calculated and experimental values showed good agreement.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100886n

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11244–11249

Titre :	Hydrolysis of ethyl lactate coupled by vapor permeation using polydimethylsiloxane / ceramic composite membrane
Type de document :	texte imprimé
Auteurs :	Weixing Li, Auteur ; Xiujuan Zhang, Auteur ; Weihong Xing, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11244–11249
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Hydrolysis Composite membrane
Résumé :	As a reversible reaction, the hydrolysis conversion of ethyl lactate is controlled by thermodynamic equilibrium. In order to improve the yield and conversion rate of hydrolysis of ethyl lactate, ethanol in the products should be removed in time. Hydrolysis of ethyl lactate coupled by vapor permeation (VP) for removing ethanol in the products was proposed. Here, the vapor permeation was carried out with a new polydimethylsiloxane (PDMS)/ceramic composite membrane prepared by our team. The PDMS/ceramic composite membrane was first characterized by scanning electron microscopy (SEM) images, pervaporation, and vapor permeation of ethanol/water mixtures. The characterization results showed that the PDMS/ceramic composite membrane was dense and uniform and had good separation performances. The permeate flux of pervaporation of 5 wt % ethanol arrived at 2541 g·m−2·h−1, and the separation factor was 7.5 at 353 K. As for vapor permeation of 10 wt % ethanol, the permeate flux was above 400 g·m−2·h−1 and separation factor was around 11. Then, the VP aided hydrolysis of ethyl lactate was investigated with the prepared PDMS/ceramic composite membrane. By coupling with VP, the final conversion of the ethyl lactate increased from 77.1% to 98.2% with the initial molar ratio of water to ethyl lactate 10:1 at 358 K. The larger initial molar ratio of water to ethyl lactate was helpful to improve the conversion of VP aided hydrolysis of ethyl lactate. The VP aided hydrolysis of ethyl lactate with the prepared PDMS/ceramic composite membrane was significantly enhanced.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100413n

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11232–11243

Titre :	Industrial loop reactor for catalytic propylene polymerization : dynamic modeling of emergency accidents
Type de document :	texte imprimé
Auteurs :	Zheng-Hong Luo, Auteur ; Pei-Lin Su, Auteur ; Wei Wu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11232–11243
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Catalytic Propylene Polymerization
Résumé :	In industrial loop reactors for catalytic propylene polymerization, the reactor pressure can influence the polymerization rate, feed flow rate, and product properties, especially safe operation of the reactor. To predict the pressure change during polymerization and check the performance of pressure-relief devices in response to emergency accidents, a dynamic model was developed based on mass and energy balances as well as thermodynamics and kinetics. In this model, the pressure was related to the temperature by a state equation for high-pressure liquid. The pipeline equations of the reactors described by the conservation of mechanical energy were incorporated into the model to better predict the pressure. In addition to the pressure, the model can also predict other variables, such as temperature, slurry density, and solids holdup in the reactors. Dynamic data from an industrial plant were used for model validation. Furthermore, the application of the model was demonstrated by simulating several typical emergency accidents.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1003784

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11221–11231

Titre :	Visbreaking studies in the presence of soaker internals
Type de document :	texte imprimé
Auteurs :	Rohit P. Kulkarni, Auteur ; Aniruddha B. Pandit, Auteur ; Jyeshtharaj B. Joshi, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11221–11231
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Visbreaking
Résumé :	Coil-soaker visbreaking is a well-proven technology in terms of lower capital investment, lower operating cost, and low susceptibility to operational upsets. A significant improvement in the performance of this technology can be achieved by incorporating suitable internals in the soaker. In the present work, visbreaking studies using vacuum residues obtained from Indian refineries were performed in a pilot plant equipped with soaker. The soaker was retrofitted with a set of in-house-developed internals. Two different configurations of internals along with a benchmark case of soaker without internals were studied for three vacuum residue feeds. The coil outlet temperature was varied in the range of 410−440 °C, while the soaker outlet pressure was maintained constant at 1.2 MPa. The resulting visbroken products, namely, gas (G, C1−C4), gasoline (60−150 °C), light gas oil (LGO, 150−350 °C), vacuum gas oil (VGO, 350−500 °C), and vacuum residue (VR, lumped product consisting of compounds with normal boiling point above 500 °C [500 °C+]) were quantified and characterized in detail. The effect of internals has been studied on the conversion and the selectivity of the visbreaking reactions. The work brings out the advantages of internals in the visbreaking technology.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie901954z

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11214-11220

Titre :	Application of Photo-oxidative Processes for the Remediation of Bleached Kraft Pulp Effluent
Type de document :	texte imprimé
Auteurs :	Teresa Cristina Fonseca Silva, Auteur ; Claudio Mudado Silva, Auteur ; Cesar Reis, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11214-11220
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Decontamination Oxidation
Résumé :	Photo-Fenton, H2O2/UV, and H2O2/TiO2/UV processes were tested and optimized to remediate organic material from bleached pulp mill effluent. Those processes were considered as part of a tertiary treatment protocol in which the optimal pH conditions for successful installation of the processes were analyzed. In the photo-Fenton and H2O2/TiO2/UV processes, a response curve was constructed to obtain the best relative proportions for the concentrations of the reagents inside and outside the experimental space. All experimental conclusions were drawn by the analysis of the relevant COD, color, and TOC data. One of the chief findings in this work is that among the photo-oxidative paths employed, the photo-Fenton treatment furnished the highest reduction in COD (78%) and TOC (91%) via the application of a concentration ratio of H2O2 to Fe2+ of 700:3.8 (mg L 1). The H2O2/UV process demonstrated a high removal of COD (61%), color (100%), and TOC (86%) when the H2O2 concentrations were 500 mg L-1. The application of a photo-Fenton process, a heterogeneous photocatalysis coupled with hydrogen peroxide (H2O2/Fe2+/UV), can be considered as more meritorious in a materials sense relative to the H2O2/UV process because lower H2O2 amounts are used. In a broad tertiary remediation perspective, all photo-oxidative processes using high H2O2 concentrations achieved COD reductions in the range of 60-70% removal, 100% color removal, and a 70-90% reduction range for TOC.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437815

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11206–11213

Titre :	Amine, melamine, and amide N - halamines as antimicrobial additives for polymers
Type de document :	texte imprimé
Auteurs :	Xinbo Sun, Auteur ; Zhengbing Cao, Auteur ; Nuala Porteous, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11206–11213
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Amine Melamine Antimicrobial Polymers
Résumé :	N-Chloro-2,2,6,6-tetramethyl-4-piperidinol laurate (Cl-TMPL) was prepared by reacting 2,2,6,6-tetramethyl-4-piperidinol hydrochloride (TMP·HCl) with lauroyl chloride, followed by chlorination with sodium dichloroisocyanurate. The chemical structure of Cl-TMPL was characterized with FT-IR, NMR, DSC, and TGA analyses. The antimicrobial performance of Cl-TMPL against Gram-positive and Gram-negative bacteria was compared with 1-chloro-3-dodecyl-5,5-dimethylhydantoin (Cl-DDMH), an amide N-halamine, and chloro-2,4-diamino-6-dodecyl-1,3,5-triazine (Cl-DADT), a melamine (imino) N-halamine. The three classes of N-halamines were used as additives for polyurethane (PU). Visible light transparency data indicated that up to 6% of Cl-DDMH or Cl-DADT could be compatibly mixed with PU, but Cl-TMPL had low compatibility with PU at higher than 2% of Cl-TMPL. With the same additive content, Cl-DDMH and Cl-DADT provided more powerful antimicrobial and biofilm-controlling effects than Cl-TMPL. In stability studies, however, PU samples with Cl-TMPL released the lowest amount of active chlorine into the immersing solution, suggesting the highest stability of the antimicrobial and biofilm-controlling efficacy.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101519u

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11200-11205

Titre :	An Approach to Industrial Application : Influence of Black Liquor and pH on Xylanase Efficiency in Bleaching of Eucalyptus Kraft Pulp
Type de document :	texte imprimé
Auteurs :	Ursula Fillat, Auteur ; M. Blanca Roncero, Auteur ; Alexandre Bassa, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11200-11205
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Bleaching pH Black liquor
Résumé :	To obtain a more realistic appraisal of the potential efficiency of xylanases in the industrial bleaching, the influence of pH and the presence of black liquor (measured as COD) on the bleaching efficiency of two commercial xylanases was studied at high temperature. These pH’s, CODs, and temperatures are close to those used in the storage tower of the B fiber line in Jacareí unit of Fibria (Brazil). The pulp samples obtained after each bleaching stage were analyzed for kappa number, brightness, viscosity, and hexenuronic acid content, and so were the effluents for COD, TOC, color, turbidity, and pH after the enzymatic stage. On the basis of the results, the xylanases were found to increase pulp brightness in the treatment involving the most unfavorable conditions (viz. high COD and pH). However, an initial COD above 9 kgO2 t−1 and/or a pH higher than 9.5 detracted from their bleaching efficiency. The effect on the kappa number and hexenuronic acids content of the pulp was apparent immediately after the enzymatic stage, and the most marked increase in brightness was observed after the chlorine dioxide stage.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437813

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11195–11199

Titre :	Conversion of ceramic UO2 pellets for HTR - 10 Fuel elements into nitrate with N2O4
Type de document :	texte imprimé
Auteurs :	Liyang Zhu, Auteur ; Wuhua Duan, Auteur ; Jingming Xu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11195–11199
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Ceramic Pellets
Résumé :	A 10 MW high-temperature gas-cooled reactor (HTR-10) has been constructed in China. It is important to study reprocessing of spent nuclear fuel from high-temperature gas-cooled reactor (HTGR) for recovery of nuclear resource and reduction of nuclear waste. Ceramic UO2 pellets of 0.5 mm in diameter for HTR-10 fuel elements were converted into nitrate with N2O4. When the molar ratio of water to uranium was 6, the conversion efficiency was above 99% after 180 min at 80 °C, and the conversion product was a mixture of UO2(NO3)2·3H2O and UO2(NO3)2·6H2O. When ceramic UO2 pellets were transformed to U3O8 powder with a particle size below 100 μm under an O2 stream and high temperature, the U3O8 powder was quickly converted into nitrate with N2O4 within 45 min. Water showed a significant effect on the reaction of U3O8 powder with N2O4, whereas other operation conditions had little effect on the reaction.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101325n

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11188–11194

Titre :	Effect of phenyl derivatization on the stabilities of antimicrobial N - chlorohydantoin derivatives
Type de document :	texte imprimé
Auteurs :	Hasan B. Kocer, Auteur ; S. D. Worley, Auteur ; R. M. Broughton, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11188–11194
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Antimicrobial
Résumé :	Phenyl substitution at position 5 on the hydantoin ring of a series of N-halamine derivatives, including an antimicrobial siloxane used for coating surfaces, has been employed to better understand the biocidal activities and stabilities of these compounds in the presence of water and exposure to ultraviolet irradiation. This phenyl derivatization of the hydantoin ring at its 5 position does, in fact, affect the antimicrobial efficacy of the siloxane against Staphylococcus aureus and Escherichia coli O157:H7, and its stability toward hydrolyses and ultraviolet light exposure. The phenyl substitution caused weakening of the N−Cl bond at the 1 position on the hydantoin ring, leading to an increase in biocidal activity but a decrease in stability. Model compounds were studied experimentally and theoretically at the (U)B3LYP/6-311++G(2d,p) level of theory in order to better explain the observations. It was found that the phenyl moiety at position 5 on the hydantoin ring can interact with the oxidative chlorine atom bonded to the amide nitrogen atom at position 1 which then results in a less stable N−Cl bond.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101258s

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11182–11187

Titre :	Enhanced cyanogen chloride removal by the reactive zirconium hydroxide substrate
Type de document :	texte imprimé
Auteurs :	Gregory W. Peterson, Auteur ; George W. Wagner, Auteur ; Jennifer H. Keller, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11182–11187
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Microporous Zirconium Hydroxide
Résumé :	A novel microporous sorbent consisting of zirconium hydroxide impregnated with triethylenediamine (TEDA) was evaluated for the removal of cyanogen chloride. Breakthrough data were collected on packed beds, illustrating the efficacious nature of TEDA and the enhanced cyanogen chloride removal from the basic zirconium hydroxide structure. NMR and XPS analyses revealed the fate of cyanogen chloride, with inorganic chloride byproducts deposited on the surface of the material and polymerized urea condensates physically adsorbed in the pore structure. The zirconium hydroxide media were found to provide significantly enhanced removal capabilities as compared to traditionally impregnated activated carbons, allowing for the development of respirators with reduced encumbrance.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101204e

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11176–11181

Titre :	Preparation of 5 - fluorouracil / B - cyclodextrin complex intercalated in layered double hydroxide and the Controlled drug release properties
Type de document :	texte imprimé
Auteurs :	Lan Jin, Auteur ; Qing Liu, Auteur ; Zhiyong Sun, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11176–11181
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Preparation Fluorouracil Cyclodextrin Hydroxide
Résumé :	Hydrophobic anticancer drug 5-fluorouracil (5-FU) has been included in the carboxymethyl modified β-cyclodextrin (CMCD), and the inclusion complex (5-FU/CMCD) was further intercalated into galleries of a zinc aluminum layered double hydroxide (ZnAl-LDH) by the ion-exchange method. Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and UV-vis spectroscopy indicate a successful intercalation of 5-FU/CMCD into the LDH gallery. The release behavior of 5-FU from drug/CMCD-LDH composite at different pH values was studied. It was found that 5-FU was released faster in pH 7.2 than in the acidic mediums (pH 4.8), and the released amount was higher. The introduction of CMCD into the LDH matrix could prolong the drug release time in comparison to that from LDH without CMCD, which can be attributed to the inclusion of 5-FU by the CMCD cavity. Studies on mathematical modeling of drug release show that the release of 5-FU from the drug/CMCD-LDH composite follows the Korsmeyer-Peppas equation very well at different pH values. The drug/CMCD inclusion complex intercalated LDH composite in this work provides a supramolecular formulation for controlled release behavior, which can be potentially applied for nonionic and hydrophobic drugs.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100990z

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11170-11175

Titre :	Investigations of the thermal properties, nucleation kinetics, and growth of y - aminobutyric acid in aqueous ethanol solution
Type de document :	texte imprimé
Auteurs :	Wenge Yang, Auteur ; Ziyu Lei, Auteur ; Yonghong Hu, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11170-11175
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Kinetics Thermal properties
Résumé :	DSC studies show that a sample starts to melt at 190.6 °C with a high melting enthalpy of 343.4 J/g. Using a laser monitoring system, the solubility of γ-aminobutyric acid in aqueous ethanol solution was measured by a synthetic method at temperatures ranging from 288.2 to 313.2 K and at atmospheric pressure; these are important data for the crystallization process of γ-aminobutyric acid from its aqueous solution. The measured solubility was correlated with the Buchowski-Ksiązczak equation and the modified Apelblat equation. Then, the induction of γ-aminobutyric acid in ethanol was estimated at different temperatures. The study reveals that the induction period of γ-aminobutyric acid decreases with increasing supersaturation. Interfacial tension was estimated from the experimentally determined induction period values. Nucleation parameters were also investigated based on classical nucleation theory. The grown crystals were also subjected to structural and thermal studies.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=23437808

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11142–11169

Titre :	Less - common nanostructures in the forms of vegetation
Type de document :	texte imprimé
Auteurs :	Oxana V. Kharissova, Auteur ; Boris I. Kharisov, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11142–11169
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Nanostructures
Résumé :	Nanostructures in the forms of varieties of vegetation are reviewed, in particular nanotrees and their agglomerates, nanobushes, nanomushrooms, nanoflowers, nanograss, and nanosheafs, among many others. Synthesis methods, influence of reaction conditions on the structural types of products, properties, formation mechanisms, and current and future applications are discussed. These nanostructures possess a series of useful properties (magnetic, semiconducting, field-emission, etc.) and applications, mainly in catalysis, as well as for creation of nanomaterials, solar cells, and in medicine for tumor treatments, among other uses.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1017139

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11131–11141

Titre :	Industrial requirements for thermodynamics and transport properties
Type de document :	texte imprimé
Auteurs :	Eric Hendriks, Auteur ; Georgios M. Kontogeorgis, Auteur ; Ralf Dohrn, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11131–11141
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Thermodynamics Transport properties
Résumé :	This work reports the results of an investigation on industrial requirements for thermodynamic and transport properties carried out by the Working Party on Thermodynamic and Transport properties (http://www.wp-ttp.dk/) of the European Federation of Chemical Engineering, EFCE (http://www.efce.info/). A carefully designed questionnaire was sent to a number of key technical people in companies in the oil and gas, chemicals, and pharmaceutical/biotechnology sectors. Twenty-eight companies have provided answers which formed the basis for the analysis presented here. A number of previous reviews, specifically addressed to or written by industrial colleagues, are discussed initially. This provides the context of the survey and material with which the results of the survey can be compared. The results of the survey have been divided into the themes: data, models, systems, properties, education, and collaboration. The main results are as follows. There is (still) an acute need for accurate, reliable, and thermodynamically consistent experimental data. Quality is more important than quantity. Similarly, there is a great need for reliable predictive, rather than correlative, models covering a wide range of compositions, temperatures, and pressures and capable of predicting primary (phase equilibrium) and secondary (enthalpy, heat capacity, etc.) properties. It is clear that the ideal of a single model covering all requirements is not achievable, but there is a consensus that this ideal should still provide the direction for future development. The use of new methods, such as SAFT, is increasing, but they are not yet in position to replace traditional methods such as cubic equations of state (especially in oil and gas industry) and the UNIFAC group contribution approach. A common problem with novel methods is lack of standardization, reference data, and correct and transparent implementations, especially in commercially available simulation programs. The survey indicates a great variety of systems where further work is required. For instance, for electrolyte systems better models are needed, capable of describing all types of phase behavior and mixtures with other types of components. There is also a lack of data and methods for larger complex molecules. Compared with the previous reviews, complex mixtures containing carbon dioxide associated with a wide range of applications, such as capture, transport, and storage are becoming interesting to a number of survey participants. Despite the academic success of molecular simulation techniques, the survey does not indicate great interest in it or its future development. Algorithms appear to be a neglected area, but improvements are still needed especially for multiphase reactive systems (simultaneous chemical and physical equilibrium). Education in thermodynamics is perceived as key, for the future application of thermodynamics in the industry. A number of suggestions for improvement were made at all three levels (undergraduate, postgraduate, and professional development) indicating that the education is correctly perceived as an ongoing process.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie101231b

[article]
in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11121–11130

Titre :	Reflections on the solubility of cellulose
Type de document :	texte imprimé
Auteurs :	Andre Pinkert, Auteur ; Kenneth N. Marsh, Auteur ; Shusheng Pang, Auteur
Année de publication :	2011
Article en page(s) :	pp. 11121–11130
Note générale :	Chimie industrielle
Langues :	Anglais (eng)
Mots-clés :	Cellulose Biopolymers Biofuels
Résumé :	Wood cellulose can be used for producing biofuels and biopolymers, thus offering a solution to global concerns on the excessive use of fossil fuels. This requires a cellulose solvent that also allows the ecofriendly processing of selective wood components. Some ionic liquids (ILs) have shown promising results as cellulose solvents with many advantages over traditional approaches. It is agreed that their ionic nature is responsible for cleaving hydrogen bonds between cellulose chains, resulting in dissolution of the biopolymer. However, it is still necessary to establish a structural relationship between IL cations and anions, which explains why only certain ion combinations show the ability to dissolve cellulose. This work aims to analyze the structural similarities displayed by common cellulose solvents focusing on requirements for ionic liquids to qualify as such. A mutual relationship between IL anions and cations is postulated that offers an explanation for the ability or disability of certain ion combinations to dissolve the biopolymer.
DEWEY :	660
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie1006596

Industrial & engineering chemistry research / Paul, Donald R. . Vol. 49 N° 22

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