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Adsorption and photocatalytic degradation kinetics of gaseous cyclohexane in an annular fluidized bed photocatalytic reactor / Qijin Geng in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4644–4652 Titre : Adsorption and photocatalytic degradation kinetics of gaseous cyclohexane in an annular fluidized bed photocatalytic reactor Type de document : texte imprimé Auteurs : Qijin Geng, Auteur ; Qingjie Guo, Auteur ; Xuehai Yue, Auteur Année de publication : 2010 Article en page(s) : pp. 4644–4652 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetics  Photocatalytic Résumé : The adsorption and photocatalytic degradation kinetics of gaseous cyclohexane using nano-titania agglomerates were investigated in an annular fluidized bed photocatalytic reactor (AFBPR). A series of adsorption and photocatalytic degradation kinetic equations were developed to explore the relationship of adsorption/degradation efficiency and operating variables based on Langmuir adsorption law and photocatalytic elementary reactions. The adsorption equilibrium constant, adsorption active sites, and apparent reaction rate coefficient of cyclohexane were determined by linear regression analysis with variation of gas velocity and relative humidity (RH). It has been demonstrated that the initial concentration, RH, and gas velocity have obviously influenced the adsorption/photocatalytic degradation efficiency and corresponding kinetic parameters. In the adsorption process, the variation of adsorption sites and adsorption efficiency with gas velocity indicated that the adsorption controlling step was related to gas velocity. In the photocatalytic degradation process, the relationship of photocatalytic degradation efficiency and RH indicates that the water molecule played a promotion role in photocatalytic degradation of cyclohexane below a humidity inflection point, while it played an inhibition role in photocatalytic degradation of cyclohexane after this point. In addition, the optimal operating conditions were determined according to the maximum degradation efficiency with respect to RH at 20% and the fluidization number at 1.62. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100114e [article] Adsorption and photocatalytic degradation kinetics of gaseous cyclohexane in an annular fluidized bed photocatalytic reactor [texte imprimé] / Qijin Geng, Auteur ; Qingjie Guo, Auteur ; Xuehai Yue, Auteur . - 2010 . - pp. 4644–4652. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4644–4652 Mots-clés : Kinetics  Photocatalytic Résumé : The adsorption and photocatalytic degradation kinetics of gaseous cyclohexane using nano-titania agglomerates were investigated in an annular fluidized bed photocatalytic reactor (AFBPR). A series of adsorption and photocatalytic degradation kinetic equations were developed to explore the relationship of adsorption/degradation efficiency and operating variables based on Langmuir adsorption law and photocatalytic elementary reactions. The adsorption equilibrium constant, adsorption active sites, and apparent reaction rate coefficient of cyclohexane were determined by linear regression analysis with variation of gas velocity and relative humidity (RH). It has been demonstrated that the initial concentration, RH, and gas velocity have obviously influenced the adsorption/photocatalytic degradation efficiency and corresponding kinetic parameters. In the adsorption process, the variation of adsorption sites and adsorption efficiency with gas velocity indicated that the adsorption controlling step was related to gas velocity. In the photocatalytic degradation process, the relationship of photocatalytic degradation efficiency and RH indicates that the water molecule played a promotion role in photocatalytic degradation of cyclohexane below a humidity inflection point, while it played an inhibition role in photocatalytic degradation of cyclohexane after this point. In addition, the optimal operating conditions were determined according to the maximum degradation efficiency with respect to RH at 20% and the fluidization number at 1.62. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100114e

Electricity generation from wastewater using an anaerobic fluidized bed microbial fuel cell / Weifang Kong in Industrial & engineering chemistry research, Vol. 50 N° 21 (Novembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12225-12232 Titre : Electricity generation from wastewater using an anaerobic fluidized bed microbial fuel cell Type de document : texte imprimé Auteurs : Weifang Kong, Auteur ; Qingjie Guo, Auteur ; Xuyun Wang, Auteur Année de publication : 2011 Article en page(s) : pp. 12225-12232 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Fuel  cell  Fluidized  bed  Fluidization  Anaerobe  Waste  water Résumé : The anaerobic fluidized bed microbial fuel cell (AFBMFC) was developed to generate electricity while simultaneously treating wastewater. During a complete cycle, the AFBMFC continuously generated electricity with a maximum power density of 1100 mW/m2 and removal of total chemical oxygen demand (COD) of 89%. To achieve this power density, the artificial electron-mediator neutral red (NR) was employed in the anode chamber. Granular biological electrodes, fluidization behavior, electron mediators, and temperature were evaluated to improve power production and wastewater treatment efficiency. The results showed that the maximum power density production of granule-graphite AFBMFC was 530 mW/m2, much higher than 410 mW/m2 using a granular activated carbon AFBMFC in the same reactor. Fluidization behaviors enhance the mass transfer and momentum transfer between activated carbon and wastewater. The power density increased with increasing methylene blue (MB) and NR concentration. Furthermore, power density reveals a slight increase as MB and NR concentrations exceed 0.5 and 1.7 mmol/L. The optimum temperature ranges from 23 to 40 °C. The Coulombic efficiency was 9.3% under the best operating conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697541 [article] Electricity generation from wastewater using an anaerobic fluidized bed microbial fuel cell [texte imprimé] / Weifang Kong, Auteur ; Qingjie Guo, Auteur ; Xuyun Wang, Auteur . - 2011 . - pp. 12225-12232. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12225-12232 Mots-clés : Fuel  cell  Fluidized  bed  Fluidization  Anaerobe  Waste  water Résumé : The anaerobic fluidized bed microbial fuel cell (AFBMFC) was developed to generate electricity while simultaneously treating wastewater. During a complete cycle, the AFBMFC continuously generated electricity with a maximum power density of 1100 mW/m2 and removal of total chemical oxygen demand (COD) of 89%. To achieve this power density, the artificial electron-mediator neutral red (NR) was employed in the anode chamber. Granular biological electrodes, fluidization behavior, electron mediators, and temperature were evaluated to improve power production and wastewater treatment efficiency. The results showed that the maximum power density production of granule-graphite AFBMFC was 530 mW/m2, much higher than 410 mW/m2 using a granular activated carbon AFBMFC in the same reactor. Fluidization behaviors enhance the mass transfer and momentum transfer between activated carbon and wastewater. The power density increased with increasing methylene blue (MB) and NR concentration. Furthermore, power density reveals a slight increase as MB and NR concentrations exceed 0.5 and 1.7 mmol/L. The optimum temperature ranges from 23 to 40 °C. The Coulombic efficiency was 9.3% under the best operating conditions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697541

Flow characteristics in a jetting fluidized bed with acoustic assistance / Qingjie Guo in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7638–7645 Titre : Flow characteristics in a jetting fluidized bed with acoustic assistance Type de document : texte imprimé Auteurs : Qingjie Guo, Auteur ; Chongdian Si, Auteur ; Zhang, Jian, Auteur Année de publication : 2010 Article en page(s) : pp. 7638–7645 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Acoustic  Fluidized  Bed Résumé : A jetting fluidized bed with acoustic assistance was employed to investigate the jet penetration depth and particle concentration profiles using an optical fiber probe. One type of FCC and two types of quartz sand particles were used as bed materials in this study. Experimental results indicated that the jet penetration depth is increased with increasing fluidizing number, jet nozzle diameter, and jet gas velocity, respectively. The jet penetration depth is decreased with an increase in particle diameter and in particle density. The semitheoretical correlations were developed to predict the jet penetration depth with and without the sound assistance. In the bubbling region, particle concentration increased with an increase in sound pressure level, which had a maximal value at a sound frequency of 150 Hz. The sound excitation had a slight influence on the particle concentration profiles in the jetting region and dense-phase particle compression region. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9016573 [article] Flow characteristics in a jetting fluidized bed with acoustic assistance [texte imprimé] / Qingjie Guo, Auteur ; Chongdian Si, Auteur ; Zhang, Jian, Auteur . - 2010 . - pp. 7638–7645. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7638–7645 Mots-clés : Acoustic  Fluidized  Bed Résumé : A jetting fluidized bed with acoustic assistance was employed to investigate the jet penetration depth and particle concentration profiles using an optical fiber probe. One type of FCC and two types of quartz sand particles were used as bed materials in this study. Experimental results indicated that the jet penetration depth is increased with increasing fluidizing number, jet nozzle diameter, and jet gas velocity, respectively. The jet penetration depth is decreased with an increase in particle diameter and in particle density. The semitheoretical correlations were developed to predict the jet penetration depth with and without the sound assistance. In the bubbling region, particle concentration increased with an increase in sound pressure level, which had a maximal value at a sound frequency of 150 Hz. The sound excitation had a slight influence on the particle concentration profiles in the jetting region and dense-phase particle compression region. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9016573

Fluidization characteristics of binary mixtures of biomass and quartz sand in an acoustic fluidized bed / Chongdian Si in Industrial & engineering chemistry research, Vol. 47 N° 23 (Décembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N° 23 (Décembre 2008) . - p. 9773–9782 Titre : Fluidization characteristics of binary mixtures of biomass and quartz sand in an acoustic fluidized bed Type de document : texte imprimé Auteurs : Chongdian Si, Auteur ; Qingjie Guo, Auteur Année de publication : 2009 Article en page(s) : p. 9773–9782 Note générale : Chemistry engineering Langues : Anglais (eng) Mots-clés : Fluidization  characteristics  Binary  mixtures  Biomass  Quartz  sand  Acoustic  fluidized  bed Résumé : The fluidization behaviors of binary mixtures of biomass and quartz sand were investigated in an acoustic bubbling fluidized bed. Two kinds of biomass particles, sawdust and wheat stalk, were employed in this test. The experiments indicated that the addition of quartz sand can improve the fluidization quality of biomass. The minimum fluidization velocity of the mixtures increased with increasing biomass content in the mixtures. A new correlation was developed for predicting the minimum fluidization velocity of different binary mixtures. The minimum fluidization velocity decreased with increasing sound pressure level and had a minimum value over the sound frequency range of 100−200 Hz. Such an acoustic fluidized bed operated in a stable or unstable fluidization regime depending on the operating conditions. According to the slope of a plot of standard deviations, unstable fluidization can be expected if the slope is greater than 50, and stable fluidization can be expected if the value is less than or equal to 50. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801070z [article] Fluidization characteristics of binary mixtures of biomass and quartz sand in an acoustic fluidized bed [texte imprimé] / Chongdian Si, Auteur ; Qingjie Guo, Auteur . - 2009 . - p. 9773–9782. Chemistry engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N° 23 (Décembre 2008) . - p. 9773–9782 Mots-clés : Fluidization  characteristics  Binary  mixtures  Biomass  Quartz  sand  Acoustic  fluidized  bed Résumé : The fluidization behaviors of binary mixtures of biomass and quartz sand were investigated in an acoustic bubbling fluidized bed. Two kinds of biomass particles, sawdust and wheat stalk, were employed in this test. The experiments indicated that the addition of quartz sand can improve the fluidization quality of biomass. The minimum fluidization velocity of the mixtures increased with increasing biomass content in the mixtures. A new correlation was developed for predicting the minimum fluidization velocity of different binary mixtures. The minimum fluidization velocity decreased with increasing sound pressure level and had a minimum value over the sound frequency range of 100−200 Hz. Such an acoustic fluidized bed operated in a stable or unstable fluidization regime depending on the operating conditions. According to the slope of a plot of standard deviations, unstable fluidization can be expected if the slope is greater than 50, and stable fluidization can be expected if the value is less than or equal to 50. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801070z

Hydrodynamics and axial dispersion in a gas−liquid−(solid) EL-ALR with different sparger designs / Changqing Cao in Industrial & engineering chemistry research, Vol. 47 n°11 (Juin 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°11 (Juin 2008) . - p. 4008–4017 Titre : Hydrodynamics and axial dispersion in a gas−liquid−(solid) EL-ALR with different sparger designs Type de document : texte imprimé Auteurs : Changqing Cao, Auteur ; Shuqin Dong, Auteur ; Qijin Geng, Auteur ; Qingjie Guo, Auteur Année de publication : 2008 Article en page(s) : p. 4008–4017 Note générale : Bibliogr. p. 4017 Langues : Anglais (eng) Mots-clés : Gs−liquid−(solid);  External-loop  airlift  reactor Résumé : The gas−liquid−(solid) three-phase hydrodynamics in an external-loop airlift reactor (EL-ALR) with an upward pipe 0.47 m in diameter and 2.5 m in height, two external loop downward pipes 0.08 m in diameter and 2.5 m in height, were investigated using four different gas sparger designs. The microconductivity probe and the three-dimensional (3-D) laser Doppler anemometry (LDA) techniques were, respectively, implemented to measure the local gas holdup in the riser (αGr) and liquid phase velocity in the downcomer (ULd) using air as the gas phase, water as the liquid phase, and alginate gel beads as the solid phase, over a wide range of operation conditions. The tracer age distribution was measured using the pulse-pursuit response technology. Axial dispersion model (ADM) was used to estimate the model parameter Peclet number (Pe) values as a fitted parameter with the measured data, using the gold partition method for nonlinear programming strategy inequation restrict conditions. The ADM gave better fits to the experimental data at high axial locations and lower superficial gas velocity (UG) for an EL-ALR used with a large L/DR ratio. A synergistic effect of ULd, αGr, Pe, solids loading (SL), and sparger designs on the performance of an EL-ALR was observed in our experiments. The sparger designs were determined to have a noticeable effect on the αGr and Pe in the lower gas velocity and lower solid loading ranges (UG < 0.025 m/s and SL < 2%), but only a slight effect in the high gas velocity and high solid loading ranges (UG > 0.030 m/s and SL > 3%). However, the effect of sparger designs on the ULd is greater in the gas velocity from 0.025 m/s to 0.045 m/s. For the lower solids loading, the increase of orifice diameter leads to a decrease in αGr. This is in accordance with what was presented in the gas−liquid two-phase system. Moreover, the influence of orifice diameters of the spargers is negligible for solids loading of >3%. Although the Pe values decreased with the operating gas velocity, the gas velocity change from 0.03 m/s to 0.04 m/s yielded lower Pe values, as a result of the reduced bubble size. As the gas velocity further increased to 0.06 m/s, the αGr and the ULd values increased, while the Pe values negligibly increased. For a gas−liquid two-phase system, Pe decreases with the orifice diameter and, for 1% of solids, Pe is also lower for sparger P-2 (ϕ 0.6 mm) than for sparger P-1 (ϕ 0.3 mm). For higher amounts of solids (3%), Pe does not have a defined trend. In addition to the gas velocity and sparger design effects, the solids loading had the effect of decreasing the ULd values, while such effect became small and flattened at high solid loadings. The ULd values, especially with VO = 100%, are ~20% lower in three-phase flow than that in two-phase flow. In addition, the ULd profiles in three-phase flow are flatter than that in two-phase flow with VO = 50%−100%, actually showing a parabolic shape rather than the almost linear one encountered in two-phase flow. This is very important for design and optimum operation that are used to systemically investigate the synergistic effect of ULd, αGr, Pe, solid loading (SL), and sparger designs on hydrodynamic performance of an EL-ALR. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0715254 [article] Hydrodynamics and axial dispersion in a gas−liquid−(solid) EL-ALR with different sparger designs [texte imprimé] / Changqing Cao, Auteur ; Shuqin Dong, Auteur ; Qijin Geng, Auteur ; Qingjie Guo, Auteur . - 2008 . - p. 4008–4017. Bibliogr. p. 4017 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°11 (Juin 2008) . - p. 4008–4017 Mots-clés : Gs−liquid−(solid);  External-loop  airlift  reactor Résumé : The gas−liquid−(solid) three-phase hydrodynamics in an external-loop airlift reactor (EL-ALR) with an upward pipe 0.47 m in diameter and 2.5 m in height, two external loop downward pipes 0.08 m in diameter and 2.5 m in height, were investigated using four different gas sparger designs. The microconductivity probe and the three-dimensional (3-D) laser Doppler anemometry (LDA) techniques were, respectively, implemented to measure the local gas holdup in the riser (αGr) and liquid phase velocity in the downcomer (ULd) using air as the gas phase, water as the liquid phase, and alginate gel beads as the solid phase, over a wide range of operation conditions. The tracer age distribution was measured using the pulse-pursuit response technology. Axial dispersion model (ADM) was used to estimate the model parameter Peclet number (Pe) values as a fitted parameter with the measured data, using the gold partition method for nonlinear programming strategy inequation restrict conditions. The ADM gave better fits to the experimental data at high axial locations and lower superficial gas velocity (UG) for an EL-ALR used with a large L/DR ratio. A synergistic effect of ULd, αGr, Pe, solids loading (SL), and sparger designs on the performance of an EL-ALR was observed in our experiments. The sparger designs were determined to have a noticeable effect on the αGr and Pe in the lower gas velocity and lower solid loading ranges (UG < 0.025 m/s and SL < 2%), but only a slight effect in the high gas velocity and high solid loading ranges (UG > 0.030 m/s and SL > 3%). However, the effect of sparger designs on the ULd is greater in the gas velocity from 0.025 m/s to 0.045 m/s. For the lower solids loading, the increase of orifice diameter leads to a decrease in αGr. This is in accordance with what was presented in the gas−liquid two-phase system. Moreover, the influence of orifice diameters of the spargers is negligible for solids loading of >3%. Although the Pe values decreased with the operating gas velocity, the gas velocity change from 0.03 m/s to 0.04 m/s yielded lower Pe values, as a result of the reduced bubble size. As the gas velocity further increased to 0.06 m/s, the αGr and the ULd values increased, while the Pe values negligibly increased. For a gas−liquid two-phase system, Pe decreases with the orifice diameter and, for 1% of solids, Pe is also lower for sparger P-2 (ϕ 0.6 mm) than for sparger P-1 (ϕ 0.3 mm). For higher amounts of solids (3%), Pe does not have a defined trend. In addition to the gas velocity and sparger design effects, the solids loading had the effect of decreasing the ULd values, while such effect became small and flattened at high solid loadings. The ULd values, especially with VO = 100%, are ~20% lower in three-phase flow than that in two-phase flow. In addition, the ULd profiles in three-phase flow are flatter than that in two-phase flow with VO = 50%−100%, actually showing a parabolic shape rather than the almost linear one encountered in two-phase flow. This is very important for design and optimum operation that are used to systemically investigate the synergistic effect of ULd, αGr, Pe, solid loading (SL), and sparger designs on hydrodynamic performance of an EL-ALR. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0715254

Investigation into photocatalytic degradation of gaseous ammonia in CPCR / Qijin Geng in Industrial & engineering chemistry research, Vol. 47 N° 13 (Juillet 2008) 

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Investigation into the behavior of reductive decomposition of calcium sulfate by carbon monoxide in chemical-looping combustion / Hongjing Tian in Industrial & engineering chemistry research, Vol. 48 N° 12 (Juin 2009) 

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Preparation and characterization of Fe2O3/Al2O3 using the solution combustion approach for chemical looping combustion / Jianshe Zhang in Industrial & engineering chemistry research, Vol. 51 N° 39 (Octobre 2012) 

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Reaction mechanism of coal chemical looping process for syngas production with CaSO4 oxygen carrier in the CO2 atmosphere / Yongzhuo Liu in Industrial & engineering chemistry research, Vol.51 N° 31 (Août 2012) 

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Stage difference equation and its application in distillation synthesis / Wende Tian in Industrial & engineering chemistry research, Vol. 48 N° 14 (Juillet 2009) 

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