CATALYSIS COMMUNICATIONS
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2019
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IF 3.674
Tingwei Zhang,Wenzhi Li,Haosheng Xin,Lele Jin,Qiying Liu
An Al 3+ -modified formaldehyde-p-hydroxybenzenesulfonic acid resin catalyst (Al-SPFR) was synthesized through a hydrothermal method. N 2 adsorption–desorption experiment and acid–base titration revealed that the Al-SPFR catalyst had better texture properties and higher strong acid content than the previously prepared unmodified SPFR . The effects of reaction time and temperature, catalyst loading, and water content in water/GVL mixture were investigated for glucose dehydration using Al-SPFR as the catalyst. An HMF yield of 47.4% was obtained at 170 °C for 2 h in the biphasic GVL/H 2 O medium. Further performing a five-cycle experiment, the HMF yield initially decreased and then remained fairly constant, and the recyclability of the Al-SPFR was reasonable.
研究领域:
化学工程
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2020
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IF 2.627
Xiaoda Wang,Wenkai Li,Shiwei Wang,Qinglian Wang,Ling Li,Hongxing Wang,Ting Qiu
Producing 2-ethyl-1-hexyl thioglycolate (ETE) via esterification reaction with thioglycolic acid (TGA) aqueous solution as raw material by reactive-separation coupling technology is a promising process intensification method. To choose suitable reactive-separation coupling strategy, the kinetic studies of the esterification of TGA with 2-ethyl-1-hexanol (EHL) were carried out in a batch system. The commercial ion exchange resin was employed as an eco-friendly catalyst. The effects of temperature, catalyst concentration and molar ratio were determined. It was interesting to observe that the equilibrium conversion of TGA increased with the increase of catalyst mass fraction due to the adsorption of product water onto resin surface. The activity-based pseudo-homogeneous (PH), Eley-Rideal (ER) and Langmuir-Hinshelwood-Hougen-Watson (LHHW) models were used to fit the kinetics data of the resin-catalyzed reaction. The models of ER and LHHW performed better than the PH model. The kinetics of the TGA-self-catalyzed reaction was also determined. An activity-based homogeneous kinetics model could well describe this self-catalyzed reaction. These results would be meaningful to the selection and design of an appropriate reaction-separation strategy for the production of ETE, to realize the process intensification.
研究领域:
化学工程
·
反应动力学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Hongbin Xia,Yuxin Wang,Rui Xia,Xinyang Xiong,Guangwen Xu,Jinggang Zhao,Jun Zhou,Lei Shi
An acetate-functionalized heterogeneous catalyst, N + -(Ac), was successfully synthesized via directed substitution of an inert site in quaternary ammonium resin by a weak-base active center and applied to the transesterification of dimethyl oxalate (DMO) with ethanol to prepare diethyl oxalate (DEO). When the optimal N + -(Ac) catalyst catalyzed the DMO transesterification with ethanol for 2 h, the DMO conversion, DEO yield, and corresponding turnover frequency (TOF) reached 93.4%, 49.7%, and 13.04 h −1 , respectively. Additionally, the synthesized N + -(Ac) exhibited catalytic universality for DMO transesterification with different alcohols, and the catalytic efficiency decreased with increasing difficulty of cleaving the hydrogen–oxygen bond from C 2 to C 4 and steric hindrance of isomeric alcohols. The pretreatment experiments of catalyst with different water content and raw materials were designed and the resin matrix, fresh catalyst, deactivated catalyst and regenerated sample were systematically analyzed using various characterization techniques to investigate the catalytic deactivation mechanism of the transesterification reaction between DMO and ethanol to synthesize DEO. The results showed that DMO played a key role in catalyst deactivation and the catalyst was deactivated upon replacement of the active sites by monomethyl oxalate anions from hydrolysis side reaction of DMO. Finally, an efficient raw material regeneration strategy for the catalyst was proposed. Herein, new theoretical support is introduced for the structural evolution of weak-base catalysts and will aid in developing heterogeneous catalysts for oxalate transesterification.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
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IF 8.198
Xiaojie Shao,Lijuan Su,Jiaojiao Zhang,Zishang Tian,Ning Zhang,Yingxiong Wang,Hongliang Wang,Xiaojing Cui,Xianglin Hou,Tiansheng Deng
The production of chemicals such as phthalic anhydride (PA) from renewable biomass is of crucial significance for sustainable social development. Herein, we demonstrate that a 99.0 mol % yield of PA can be achieved from a Diels–Alder adduct of furan and maleic anhydride on an acid resin catalyst. The active sites on the catalyst were produced by pretreating the resin with acetic anhydride. The excellent performance of the resin catalyst is attributed to its surface enrichment effect on the reactant and good ability to suppress the side reactions. Moreover, the catalyst deactivation mechanism was clarified to be the destruction of the resin skeleton during the reaction. These results will provide a practical route for the future industrial production of PA from renewable biomass.
研究领域:
化学工程
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绿色化学
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催化
·
可再生能源
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2020
·
IF 3.573
Xin Gao,Runnan Zhao,Haifeng Cong,Jian Na,Yang Shi,Hong Li,Xingang Li
The objective of the present work is to find a potential way for a great decrease in the biodiesel production energy requirement and CO2 emission from the aspects of the reactor and process. Here, for the first time, a series of pilot-scale reactive distillation (RD) experiments were conducted using the cation-exchange resin catalysts and used for biodiesel synthesis from esterification of soybean oil deodorized distillate with methanol. The reaction kinetics was also investigated at different temperatures and mole ratios of methanol to free fatty acids (FFAs). Moreover, a rigorous biodiesel synthesis model of the RD process, based on the kinetics obtained in this work, was developed and validated on the basis of experimental data. The developed modeling can be used to optimize the process and design parameters while also providing a foundation guide for industrial applications. The results demonstrated that the use of RD technology increases the conversion of FFA to 99% and keeps energy consumption and CO2 emission at a low level. Furthermore, the RD technology over cation-exchange resin catalysts will open a new path to develop a better process for biodiesel synthesis from waste oil to reduce the production energy consumption, decrease CO2 emission, and thus further increase the commercial competitiveness of this green fuel.
研究领域:
化学工程
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环境科学
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能源技术
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过程工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Yi Guo,Rui Wang,Chang Shu,Hong Li,Xin Gao
Reactive distillation (RD) can be effectively used to improve the selectivity of the intermediate product for complex multi-reaction schemes, which involves using distillation to manipulate the column profiles in the RD column (RDC) to attribute the desired reaction and the manipulating reactions to facilitate separation. As the demand for ethyl methyl carbonate (EMC) has increased significantly due to its structural characteristics, the selective synthesis of EMC from the consecutive transesterification of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of azeotropes between reactants and products was studied as featured reaction schemes. The basic resin catalyst KC161 is utilized to build the kinetic reaction model and supplement the primary data for the process design. The pilot-scale RD experiments are explored to verify the feasibility and the reliability of the model. The impact of critical operation and structure parameters on the conversion and selectivity of the reaction and the azeotropes formed in the system were analyzed. A hybrid distillation process containing an RDC, pressure-swing distillation columns, and a regular distillation column, was designed and optimized based on minimized total annual cost (TAC) using a sequential iterative algorithm. 0. 9997 (mole purity) EMC and 0. 9999 (mole purity) diethyl carbonate (DEC) were obtained with EMC selectivity up to 0.863%.
研究领域:
化学工程
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工艺化学
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工业化学
✓ 已验证
产品关联
DOI
高影响因子
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