Liquid-phase acrylic acid hydration over solid-phase catalysts is a key reaction for the industrial productionof 3-hydroxypropionic acid. However, the relevant literature primarily focuses on the experimental aspects ...Liquid-phase acrylic acid hydration over solid-phase catalysts is a key reaction for the industrial productionof 3-hydroxypropionic acid. However, the relevant literature primarily focuses on the experimental aspects of catalystscreening and exploring reaction conditions, with few accurate descriptions of the reaction kinetics and determination ofthe reaction mechanism. Here, we combined kinetics experiments and theoretical calculations to elucidate the kinetics andmechanism of acrylic acid hydration on a resin catalyst. The pseudo-homogeneous model, and Langmuir-Hinshelwood-Haugen-Watson and Elie-Riedel (ER) heterogeneous models were used to explain the experimental kinetics data. TheER model can explain the experimental data very well, suggesting strong adsorption of acrylic acid on the surface of theresin catalyst. Furthermore, density functional theory calculations show that the hydration follows a stepwise, rather than aconcerted, reaction pathway. The present study provides theoretical insights into the reaction mechanism and kinetics, fillingthe gap in our understanding of the reaction on a fundamental level.展开更多
Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether （ETBE）, from etha-nol and tert-butyl alcohol （TBA） has been studied in catalytic distillation column （CDC） using ion exchange...Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether （ETBE）, from etha-nol and tert-butyl alcohol （TBA） has been studied in catalytic distillation column （CDC） using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found：reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.展开更多
Ethoxymethxoymethane （EMM） was conveniently prepared by acetalization of aqueous formaldehyde with methanol andethanol in a batch reactive distillation mode using a cation-exchange resin catalyst for the first time....Ethoxymethxoymethane （EMM） was conveniently prepared by acetalization of aqueous formaldehyde with methanol andethanol in a batch reactive distillation mode using a cation-exchange resin catalyst for the first time. EMM was found tO be asignificant cosolvent of methano1/gasoline blends, ？ 2009 Ai You Hao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.展开更多
A synthetic technology for the production of methyl-ethyl-ketone (MEK) is introduced, which makes use of butylene catalytic hydration to produce secondary butanol (SBA) and this is followed by dehydrogenation of SBA. ...A synthetic technology for the production of methyl-ethyl-ketone (MEK) is introduced, which makes use of butylene catalytic hydration to produce secondary butanol (SBA) and this is followed by dehydrogenation of SBA. By optimizing the operating conditions of a commercial unit, the running results showed that the recom-mended process was successful and that the catalysts had high activity, good selectivity, and long lifespan, which ensured long-term running in commercial units.展开更多
In this work, free tall oil fatty acids were epoxidized with in-situ generated peroxyacetic acid. Reaction kineticsof epoxidation was investigated by oxirane content and iodine value titrimetric determination, as well...In this work, free tall oil fatty acids were epoxidized with in-situ generated peroxyacetic acid. Reaction kineticsof epoxidation was investigated by oxirane content and iodine value titrimetric determination, as well as FTIRspectra analysis. A highly functional biobased polyol was synthesized by functionalizing epoxidized tall oilfatty acids with triethanolamine using Montmorillonite K10 as a catalyst. The obtained polyol was analyzed byFTIR and MALDI-TOF MS. The most common chemical and physical characteristics of obtained polyol weredetermined.展开更多
文摘Liquid-phase acrylic acid hydration over solid-phase catalysts is a key reaction for the industrial productionof 3-hydroxypropionic acid. However, the relevant literature primarily focuses on the experimental aspects of catalystscreening and exploring reaction conditions, with few accurate descriptions of the reaction kinetics and determination ofthe reaction mechanism. Here, we combined kinetics experiments and theoretical calculations to elucidate the kinetics andmechanism of acrylic acid hydration on a resin catalyst. The pseudo-homogeneous model, and Langmuir-Hinshelwood-Haugen-Watson and Elie-Riedel (ER) heterogeneous models were used to explain the experimental kinetics data. TheER model can explain the experimental data very well, suggesting strong adsorption of acrylic acid on the surface of theresin catalyst. Furthermore, density functional theory calculations show that the hydration follows a stepwise, rather than aconcerted, reaction pathway. The present study provides theoretical insights into the reaction mechanism and kinetics, fillingthe gap in our understanding of the reaction on a fundamental level.
基金Part of this paper was included in the proceedings of World Congress on Engineering and Computer Science,San Francisco,USA,22-24 October,2008,pp.79-84(ISBN 978-988-98671-0-2)The first author is grateful to Higher Education Commission of Pakistan for funding this research under indigenous scheme
文摘Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether （ETBE）, from etha-nol and tert-butyl alcohol （TBA） has been studied in catalytic distillation column （CDC） using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found：reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.
文摘Ethoxymethxoymethane （EMM） was conveniently prepared by acetalization of aqueous formaldehyde with methanol andethanol in a batch reactive distillation mode using a cation-exchange resin catalyst for the first time. EMM was found tO be asignificant cosolvent of methano1/gasoline blends, ？ 2009 Ai You Hao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.
文摘A synthetic technology for the production of methyl-ethyl-ketone (MEK) is introduced, which makes use of butylene catalytic hydration to produce secondary butanol (SBA) and this is followed by dehydrogenation of SBA. By optimizing the operating conditions of a commercial unit, the running results showed that the recom-mended process was successful and that the catalysts had high activity, good selectivity, and long lifespan, which ensured long-term running in commercial units.
文摘In this work, free tall oil fatty acids were epoxidized with in-situ generated peroxyacetic acid. Reaction kineticsof epoxidation was investigated by oxirane content and iodine value titrimetric determination, as well as FTIRspectra analysis. A highly functional biobased polyol was synthesized by functionalizing epoxidized tall oilfatty acids with triethanolamine using Montmorillonite K10 as a catalyst. The obtained polyol was analyzed byFTIR and MALDI-TOF MS. The most common chemical and physical characteristics of obtained polyol weredetermined.
