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Adsorptive removal of saturated and unsaturated fatty acids using Ion - exchange resins / Ganesh L. Maddikeri in Industrial & engineering chemistry research, Vol. 51 N° 19 (Mai 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 19 (Mai 2012) . - pp. 6869–6876 Titre : Adsorptive removal of saturated and unsaturated fatty acids using Ion - exchange resins Type de document : texte imprimé Auteurs : Ganesh L. Maddikeri, Auteur ; Aniruddha B. Pandit, Auteur ; Parag R. Gogate, Auteur Année de publication : 2012 Article en page(s) : pp. 6869–6876 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Acids  Ion  exchange Résumé : One of the pretreatment approaches for decreasing the initial acid content of waste vegetable oil or nonedible oils with high initial free fatty acid content, with an objective of obtaining a suitable starting raw material for the production of biodiesel, is the adsorption of the free acids using ion-exchange resins. The present work deals with investigation of adsorption characteristics of saturated (stearic) and unsaturated (oleic) fatty acids on different ion exchange resins (polymeric strong (Indion 810) and weak (Indion 850 and Indion 860) anion exchange resins). The ion exchange resins contain tertiary or quaternary amino functional groups on the styrene-divinyl benzene copolymer matrix which can facilitate the adsorption of acids. Kinetic adsorption studies have been carried out initially to determine the contact time required to reach the adsorption equilibrium between fatty acid adsorbed on the resin and remaining fatty acid present in the oil. Equilibrium adsorption studies have been carried out at different temperatures viz. 293, 303, and 313 K. It has been observed that adsorption of saturated and unsaturated fatty acids increased with its concentration in the liquid at constant temperature and decreased with an increase in the temperature at constant concentration. Also, the adsorption equilibrium data have been found to be well described by the Freundlich type isotherm. The negative values of ΔG and ΔH showed that the adsorption of both saturated and unsaturated acids on the ion exchange resins was spontaneous and also exothermic. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000562 [article] Adsorptive removal of saturated and unsaturated fatty acids using Ion - exchange resins [texte imprimé] / Ganesh L. Maddikeri, Auteur ; Aniruddha B. Pandit, Auteur ; Parag R. Gogate, Auteur . - 2012 . - pp. 6869–6876. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 19 (Mai 2012) . - pp. 6869–6876 Mots-clés : Acids  Ion  exchange Résumé : One of the pretreatment approaches for decreasing the initial acid content of waste vegetable oil or nonedible oils with high initial free fatty acid content, with an objective of obtaining a suitable starting raw material for the production of biodiesel, is the adsorption of the free acids using ion-exchange resins. The present work deals with investigation of adsorption characteristics of saturated (stearic) and unsaturated (oleic) fatty acids on different ion exchange resins (polymeric strong (Indion 810) and weak (Indion 850 and Indion 860) anion exchange resins). The ion exchange resins contain tertiary or quaternary amino functional groups on the styrene-divinyl benzene copolymer matrix which can facilitate the adsorption of acids. Kinetic adsorption studies have been carried out initially to determine the contact time required to reach the adsorption equilibrium between fatty acid adsorbed on the resin and remaining fatty acid present in the oil. Equilibrium adsorption studies have been carried out at different temperatures viz. 293, 303, and 313 K. It has been observed that adsorption of saturated and unsaturated fatty acids increased with its concentration in the liquid at constant temperature and decreased with an increase in the temperature at constant concentration. Also, the adsorption equilibrium data have been found to be well described by the Freundlich type isotherm. The negative values of ΔG and ΔH showed that the adsorption of both saturated and unsaturated acids on the ion exchange resins was spontaneous and also exothermic. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000562

Intensification approaches for biodiesel synthesis from waste cooking oil / Ganesh L. Maddikeri in Industrial & engineering chemistry research, Vol. 51 N° 45 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14610–14628 Titre : Intensification approaches for biodiesel synthesis from waste cooking oil : A review Type de document : texte imprimé Auteurs : Ganesh L. Maddikeri, Auteur ; Aniruddha B. Pandit, Auteur ; Parag R. Gogate, Auteur Année de publication : 2013 Article en page(s) : pp. 14610–14628 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Biodiesel Résumé : The use of biodiesel as an alternative fuel has become more attractive recently because of its environmental benefits such as nontoxicity and biodegradability. However, due to the unfavorable economics and other problems for design and operation of large scale reactors, commercialization of biodiesel has not been significantly effective. The specific challenges in the synthesis route based on transesterification include higher separation times, high operating cost, high energy consumption, and low production efficiency due to equilibrium limitations. The present work highlights the potential use of waste cooking oil as a cheap and economical feedstock discussing the advantages of the process and limitations for transesterification reaction. Improvements in the synthesis process based on the different pretreatment methods and process intensifying techniques are discussed with specific reference to transesterification of waste cooking oil. Different physical and chemical pretreatment methods required for the preparation of feedstock include filtration, drying, acidic esterification, adsorption, crystallization, and distillation for the removal of fatty acids and other contaminants. The critical review also highlights the different process intensification techniques such as cavitational reactors, microwave irradiation, microchannel reactor, oscillatory flow reactor, use of cosolvent, and supercritical transesterification process that can be used for biodiesel production process with an objective of enhancing the reaction rate, reduction in the molar ratio of alcohol to oil, and energy input by intensifying the transport processes and overcoming the equilibrium limitations. Guidelines for the selection of optimum operating parameters have also been given with comparative analysis of the different approaches of process intensification. Finally, some recommendations have been made for the possible research that needs to be done for successful commercialization of biodiesel synthesis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301675j [article] Intensification approaches for biodiesel synthesis from waste cooking oil : A review [texte imprimé] / Ganesh L. Maddikeri, Auteur ; Aniruddha B. Pandit, Auteur ; Parag R. Gogate, Auteur . - 2013 . - pp. 14610–14628. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14610–14628 Mots-clés : Biodiesel Résumé : The use of biodiesel as an alternative fuel has become more attractive recently because of its environmental benefits such as nontoxicity and biodegradability. However, due to the unfavorable economics and other problems for design and operation of large scale reactors, commercialization of biodiesel has not been significantly effective. The specific challenges in the synthesis route based on transesterification include higher separation times, high operating cost, high energy consumption, and low production efficiency due to equilibrium limitations. The present work highlights the potential use of waste cooking oil as a cheap and economical feedstock discussing the advantages of the process and limitations for transesterification reaction. Improvements in the synthesis process based on the different pretreatment methods and process intensifying techniques are discussed with specific reference to transesterification of waste cooking oil. Different physical and chemical pretreatment methods required for the preparation of feedstock include filtration, drying, acidic esterification, adsorption, crystallization, and distillation for the removal of fatty acids and other contaminants. The critical review also highlights the different process intensification techniques such as cavitational reactors, microwave irradiation, microchannel reactor, oscillatory flow reactor, use of cosolvent, and supercritical transesterification process that can be used for biodiesel production process with an objective of enhancing the reaction rate, reduction in the molar ratio of alcohol to oil, and energy input by intensifying the transport processes and overcoming the equilibrium limitations. Guidelines for the selection of optimum operating parameters have also been given with comparative analysis of the different approaches of process intensification. Finally, some recommendations have been made for the possible research that needs to be done for successful commercialization of biodiesel synthesis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301675j

Intensification of degradation of 2,4,6-trichlorophenol using sonochemical reactors / Akshaykumar K. Shriwas in Industrial & engineering chemistry research, Vol. 50 N° 16 (Août 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 16 (Août 2011) . - pp. 9601-9608 Titre : Intensification of degradation of 2,4,6-trichlorophenol using sonochemical reactors : understanding mechanism and scale-up aspects Type de document : texte imprimé Auteurs : Akshaykumar K. Shriwas, Auteur ; Parag R. Gogate, Auteur Année de publication : 2011 Article en page(s) : pp. 9601-9608 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Scale  effect  Extrapolation  Reactor  Sonochemical  reaction Résumé : Degradation of 2,4,6-trichlorophenol (TCP) has been investigated using two types of sonochemical reactors viz. ultrasonic horn and ultrasonic bath reactors with an objective of investigating the effect of different operating parameters and intensifying the extent of degradation using different additives. Effect of different operating parameters such as operating temperature, power input, operating pH, and use of different additives such as solid particles, air, and hydrogen peroxide has been investigated. Experiments have been performed at two different scales of operation with an objective of illustrating the guidelines for possible scale-up strategies for cost-effective operation. As the extent of degradation was significantly lower in large scale reactor, intensification studies have been carried out by combining sonication with UV light and ozone. Possible mechanisms for intensification due to the use of different additives and combining oxidation techniques have also been illustrated based on the observed results. Maximum degradation has been obtained in the presence of air in the horn type reactor and in the presence of TiO2 as catalyst in larger capacity reactor. It has been observed that the use of additives which enhance the overall cavitational activity is more recommended due to the dominant pyrolytic mechanism of degradation. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24425203 [article] Intensification of degradation of 2,4,6-trichlorophenol using sonochemical reactors : understanding mechanism and scale-up aspects [texte imprimé] / Akshaykumar K. Shriwas, Auteur ; Parag R. Gogate, Auteur . - 2011 . - pp. 9601-9608. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 16 (Août 2011) . - pp. 9601-9608 Mots-clés : Scale  effect  Extrapolation  Reactor  Sonochemical  reaction Résumé : Degradation of 2,4,6-trichlorophenol (TCP) has been investigated using two types of sonochemical reactors viz. ultrasonic horn and ultrasonic bath reactors with an objective of investigating the effect of different operating parameters and intensifying the extent of degradation using different additives. Effect of different operating parameters such as operating temperature, power input, operating pH, and use of different additives such as solid particles, air, and hydrogen peroxide has been investigated. Experiments have been performed at two different scales of operation with an objective of illustrating the guidelines for possible scale-up strategies for cost-effective operation. As the extent of degradation was significantly lower in large scale reactor, intensification studies have been carried out by combining sonication with UV light and ozone. Possible mechanisms for intensification due to the use of different additives and combining oxidation techniques have also been illustrated based on the observed results. Maximum degradation has been obtained in the presence of air in the horn type reactor and in the presence of TiO2 as catalyst in larger capacity reactor. It has been observed that the use of additives which enhance the overall cavitational activity is more recommended due to the dominant pyrolytic mechanism of degradation. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24425203

Intensification of synthesis of biodiesel from nonedible oils using sonochemical reactors / Vitthal L. Gole in Industrial & engineering chemistry research, Vol. 51 N° 37 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 37 (Septembre 2012) . - pp. 11866–11874 Titre : Intensification of synthesis of biodiesel from nonedible oils using sonochemical reactors Type de document : texte imprimé Auteurs : Vitthal L. Gole, Auteur ; Parag R. Gogate, Auteur Année de publication : 2012 Article en page(s) : pp. 11866–11874 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Biodiesel Résumé : Biodiesel synthesis from nonedible oils, which offer excellent potential as sustainable feed stock, is highly energy-intensive and slow operation, because it requires considerable processing due to higher initial acid values and due to the fact that the reaction is mass-transfer-controlled. The present work reports the intensification of synthesis of biodiesel from the high-acid-value Nagchampa oil using sonochemical reactors. The synthesis process is a two-step method of esterification in the presence of homogeneous acid catalyst followed by transesterification using an alkaline (KOH) catalyst. The synthesis has also been attempted using conventional methods of reflux for analyzing the degree of intensification. With an objective of avoiding possible saponification reaction in the transesterification based on use of an alkaline catalyst, the acid value of oil was reduced from 18.4 mg KOH/g of oil to 1.4 mg KOH/g of oil, using the first-stage esterification method. The reduction in the acid value allows for an efficient second transesterification stage. The reaction temperature, molar ratio, and catalyst concentration were optimized for esterification and transesterification stages for the ultrasound and conventional techniques. It has been observed that the reaction temperature and reaction time required for esterification, as well as the transesterification stages, are substantially lower in the case of sonochemical reactors, compared to the conventional heating method. Also, the percentage excess of the reactants is significantly reduced, leading to energy savings in the subsequent separation processes for getting the purified product. Overall, the present work has clearly established the efficacy of sonochemical reactors for the intensification of biodiesel synthesis based on a sustainable raw material. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2029442 [article] Intensification of synthesis of biodiesel from nonedible oils using sonochemical reactors [texte imprimé] / Vitthal L. Gole, Auteur ; Parag R. Gogate, Auteur . - 2012 . - pp. 11866–11874. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 37 (Septembre 2012) . - pp. 11866–11874 Mots-clés : Biodiesel Résumé : Biodiesel synthesis from nonedible oils, which offer excellent potential as sustainable feed stock, is highly energy-intensive and slow operation, because it requires considerable processing due to higher initial acid values and due to the fact that the reaction is mass-transfer-controlled. The present work reports the intensification of synthesis of biodiesel from the high-acid-value Nagchampa oil using sonochemical reactors. The synthesis process is a two-step method of esterification in the presence of homogeneous acid catalyst followed by transesterification using an alkaline (KOH) catalyst. The synthesis has also been attempted using conventional methods of reflux for analyzing the degree of intensification. With an objective of avoiding possible saponification reaction in the transesterification based on use of an alkaline catalyst, the acid value of oil was reduced from 18.4 mg KOH/g of oil to 1.4 mg KOH/g of oil, using the first-stage esterification method. The reduction in the acid value allows for an efficient second transesterification stage. The reaction temperature, molar ratio, and catalyst concentration were optimized for esterification and transesterification stages for the ultrasound and conventional techniques. It has been observed that the reaction temperature and reaction time required for esterification, as well as the transesterification stages, are substantially lower in the case of sonochemical reactors, compared to the conventional heating method. Also, the percentage excess of the reactants is significantly reduced, leading to energy savings in the subsequent separation processes for getting the purified product. Overall, the present work has clearly established the efficacy of sonochemical reactors for the intensification of biodiesel synthesis based on a sustainable raw material. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2029442

Intensification of synthesis of cumene hydroperoxide using sonochemical reactors / Vivek P. Chavan in Industrial & engineering chemistry research, Vol. 50 N° 22 (Novembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 22 (Novembre 2011) . - pp. 12433-12438 Titre : Intensification of synthesis of cumene hydroperoxide using sonochemical reactors Type de document : texte imprimé Auteurs : Vivek P. Chavan, Auteur ; Parag R. Gogate, Auteur Année de publication : 2012 Article en page(s) : pp. 12433-12438 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Reactor  Sonochemical  reaction Résumé : Intensification of chemical synthesis is a key research area due to the current constraints before the chemical industry due to competition as well as economics and demand for greener routes of processing. The present work illustrates the use of sonochemical reactors for the intensification of synthesis of cumene hydroperoxide from cumene. Air oxidation of cumene in the presence of cupric oxide powder as a catalyst has been investigated using a conventional approach and different sonochemical reactors such as an ultrasonic bath and a probe sonicator. Optimization of different operating parameters such as stirrer speed, temperature, catalyst quantity, air flow rate, and cumene hydroperoxide as an initiator have been investigated using conventional stirring method. The optimum conditions for the air oxidation of the cumene process have been obtained as stirrer speed of 300 rpm, temperature as 110 °C, catalyst quantity of 3 g, and air flow rate as 500 mL/min, and cumene hydroperoxide as an initiator had a very marginal effect. In the case of ultrasound assisted synthesis approach, various parameters studied were pulse of ultrasound, power of ultrasound, and frequency of ultrasound. Enhancement in conversion of cumene and reduction in the reaction time was observed in the presence of ultrasound as compared to silent conditions. The selectivity toward cumene hydroperoxide was marginally affected by the use of ultrasonic conditions. The maximum conversion obtained using ultrasound was 67.1% when 40 kHz frequency of ultrasound horn was used in 4 h, while 50.4% conversion was obtained in 8 h of reaction under otherwise similar operating conditions. The obtained selectivity was always greater than 95% for all conditions considered in the work. The present work has clearly revealed that substantial intensification is obtained for the synthesis of cumene hydroperoxide using ultrasound as compared to the conventional approach. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24745716 [article] Intensification of synthesis of cumene hydroperoxide using sonochemical reactors [texte imprimé] / Vivek P. Chavan, Auteur ; Parag R. Gogate, Auteur . - 2012 . - pp. 12433-12438. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 22 (Novembre 2011) . - pp. 12433-12438 Mots-clés : Reactor  Sonochemical  reaction Résumé : Intensification of chemical synthesis is a key research area due to the current constraints before the chemical industry due to competition as well as economics and demand for greener routes of processing. The present work illustrates the use of sonochemical reactors for the intensification of synthesis of cumene hydroperoxide from cumene. Air oxidation of cumene in the presence of cupric oxide powder as a catalyst has been investigated using a conventional approach and different sonochemical reactors such as an ultrasonic bath and a probe sonicator. Optimization of different operating parameters such as stirrer speed, temperature, catalyst quantity, air flow rate, and cumene hydroperoxide as an initiator have been investigated using conventional stirring method. The optimum conditions for the air oxidation of the cumene process have been obtained as stirrer speed of 300 rpm, temperature as 110 °C, catalyst quantity of 3 g, and air flow rate as 500 mL/min, and cumene hydroperoxide as an initiator had a very marginal effect. In the case of ultrasound assisted synthesis approach, various parameters studied were pulse of ultrasound, power of ultrasound, and frequency of ultrasound. Enhancement in conversion of cumene and reduction in the reaction time was observed in the presence of ultrasound as compared to silent conditions. The selectivity toward cumene hydroperoxide was marginally affected by the use of ultrasonic conditions. The maximum conversion obtained using ultrasound was 67.1% when 40 kHz frequency of ultrasound horn was used in 4 h, while 50.4% conversion was obtained in 8 h of reaction under otherwise similar operating conditions. The obtained selectivity was always greater than 95% for all conditions considered in the work. The present work has clearly revealed that substantial intensification is obtained for the synthesis of cumene hydroperoxide using ultrasound as compared to the conventional approach. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24745716

Optimization of a hydrodynamic cavitation reactor using salicylic acid dosimetry / Lekhraj P. Amin in Chemical engineering journal, Vol. 156 N° 1 (Janvier 2010) 

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Removal of p-nitrophenol using hydrodynamic cavitation and Fenton chemistry at pilot scale operation / Amey A. Pradhan in Chemical engineering journal, Vol. 156 N° 1 (Janvier 2010) 

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Ultrasound assisted cooling crystallization of sodium acetate / Ujwal N. Hatkar in Industrial & engineering chemistry research, Vol. 51 N° 39 (Octobre 2012) 

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Ultrasound-assisted synthesis of biodiesel from palm fatty acid distillate / Vishwanath G. Deshmane in Industrial & engineering chemistry research, Vol. 48 N° 17 (Septembre 2009) 

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