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Novel eco-efficient reactive distillation process for dimethyl carbonate production by indirect alcoholysis of urea

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Frontiers of Chemical Science and Engineering 2022年第2期16卷 316-331页

作者： Iulian Patrașcu Costin S.Bîldea Anton A.Kiss Department of Chemical and Biochemical Engineering University“Politehnica”of Bucharest011061 BucharestRomania Department of Chemical Engineering and Analytical Science The University of ManchesterManchester M139PLUK

dimethyl carbonate is an eco-friendly essential chemical that can be sustainably produced from CO_(2),which is available from carbon capture activities or can even be captured from the *** rapid increase in dimethyl carbonate demand is driven by the fast growth of polycarbonates,solvent,pharmaceutical,and lithium-ion battery *** carbonate can be produced from CO_(2)through various chemical pathways,but the most convenient route reported is the indirect alcoholysis of *** research used techniques such as heat integration and reactive distillation to reduce the energy use and costs,but the use of an excess of methanol in the trans-esterification step led to an energy intensive extractive distillation required to break the dimethyl carbonate-methanol *** work shows that the production of dimethyl carbonate by indirect alcoholysis of urea can be improved by using an excess of propylene carbonate(instead of an excess of methanol),a neat feat that we showed it requires only 2.64 kW·h·kg^(-1) dimethyl carbonate in a reaction-separation-recycle process,and a reactive distillation column that effectively replaces two conventional distillation columns and the reactor for dimethyl carbonate ***,less equipment is required,the methanol-dimethyl carbonate azeotrope does not need to be recycled,and the overall savings are ***,we propose the use of a reactive distillation column in a heat integrated process to obtain high purity dimethyl carbonate(>99.8 wt-%).The energy requirement is reduced by heat integration to just 1.25 kW·h·kg^(-1) dimethyl carbonate,which is about 52%lower than the reaction-separation-recycle *** benefit from the energy savings,the dynamics and control of the process are provided for10%changes in the nominal rate of 32 ktpy dimethyl carbonate,and for uncertainties in reaction kinetics.

关键词： dimethyl carbonate reactive distillation process design plantwide control

Effect of dimethyl carbonate on the behavior of water confined in carbon nanotube

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Chinese Journal of Chemical Engineering 2021年第3期34卷 177-185页

作者： Qingwei Gao Yumeng Zhang Aatto Laaksonen Yudan Zhu Xiaoyan Ji Shuangliang Zhao Yaojia Chen Xiaohua Lu College of Chemical Engineering State Key Laboratory of Materials-oriented Chemical EngineeringNanjing Tech UniversityNanjing 211816China Energy Engineering Division of Energy ScienceLuleåUniversity of Technology97187 LuleåSweden State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm UniversitySE-10691 StockholmSweden Centre of Advanced Research in Bionanoconjugates and Biopolymers Petru Poni Institute of Macromolecular ChemistryAleea Grigore Ghica-Voda41A700487 IasiRomania Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

The dehydration of water by dimethyl carbonate(DMC)is of great significance for its application in electrochemistry and oil *** the rapid development of nanomaterial,one-dimensional(*** nanotube(CNT))and two-dimensional(*** graphene)materials have been widely used for molecular *** this work,the molecular behavior of dimethyl carbonate/water mixture confined in CNT with varying diameters was studied based on molecular dynamics *** to different van der Waals interactions for the components in the mixtures with the solid surface,DMC molecules are preferentially adsorbed on the inner surface of the pore wall and formed an adsorption *** with the pure water molecules confined in CNT,the adsorption DMC layer shows notable effect on the local compositions and microstructures of water molecules under nanoconfinement,which may result in different water *** analysis shows that the surface-induced DMC molecules can destroy the hydrogen bonding network of water molecules and result in an uniform and dispersed distribution of water molecules in the *** clear molecular understandings can be useful in material design for membrane separation.

关键词： dimethyl carbonate Carbon nanotube Solid/fluid interface Adsorbed layer Molecular simulation

Vapor-Liquid Equilibria for dimethyl carbonate-n-Butyl Acetate Binary System at 101.325kPa

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Chinese Journal of Chemical Engineering 1999年第1期7卷 83-85页

作者：施云海李文清涂晋林华东理工大学化工所上海

The vapor-liquid equilibrium (VLE) data for the dimethyl carbonate-n-butyl acetate binary system were measured by an Ellis equilibrated distillator. The experimental data were checked for their thermodynamic consistency through statistical methods. The VLE data was correlated with Wilson and NRTL activity coefficient models and also with the calculation of the vapor phase fugacity coefficient by the modified Peng-Robinson equation of state.

关键词： vapor-liquid equilibrium binary system dimethyl carbonate n-butyl acetate

Highly active Pd containing EMT zeolite catalyst for indirect oxidative carbonylation of methanol to dimethyl carbonate

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Journal of Energy Chemistry 2021年第1期30卷 191-201,I0007页

作者： Chunzheng Wang Weisong Xu Zhengxing Qin Hailing Guo Xinmei Liu Svetlana Mintova State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina Laboratoire Catalyse et Spectrochimie(LCS) Normandie UniversiteENSICAENUN1CAENCNRS6 Boulevard Marechal JuinCaen 14050France

Palladium containing EMT zeolite catalyst(Pd/EMT) was prepared and used for the indirect oxidative carbonylation of methanol to dimethyl carbonate(DMC).The EMT zeolite was employed as a new catalyst support and compared with the conventional Pd containing FAU zeolite catalyst(Pd/FAU).The Pd/EMT in contrast to the Pd/FAU catalyst exhibited high intrinsic activity with the turnover frequency of 0.25 s^(-1) vs.0.11 s^(-1).The Pd/EMT catalyst showed high CO conversion of 82% and DMC selectivity of 79%,that maintained for at least 130 h,while the activity of the Pd/FAU catalyst rapidly deteriorated within 12 *** enhanced interactions between Pd and EMT zeolite inhibited the sintering of palladium clusters and maintained the Pd2+ active sites in the Pd/EMT *** stabilization of the mono-dispersed Pd clusters within the EMT zeolite is paramount to the excellent performance of the catalyst for the indirect oxidative carbonylation of methanol to DMC.

关键词： EMT Palladium Stability Carbonylation dimethyl carbonate

A highly efficient La-modified ZnAl-LDO catalyst and its performance in the synthesis of dimethyl carbonate from methyl carbamate and methanol

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Chinese Journal of Chemical Engineering 2023年第9期61卷 9-23页

作者： Mingxue Yin Bo Jia Kuiyi You Bo Jin Yangqiang Huang Xiao Luo Zhiwu Liang College of Chemistry and Chemical Engineering the Engineering Research Center of Advanced CatalysisMinistry of EducationHunan UniversityChangsha 410082China College of Chemical Engineering Xiangtan UniversityXiangtan 411105China

In this paper,the highly efficient ZnAlLa layered double oxide(ZnAlLa-LDO)catalyst was evaluated and used in methyl carbamate(MC)alcoholysis synthesis of dimethyl *** optimal conditions,the MC conversion was 33.5% and the dimethyl carbonate(DMC)selectivity was up to 92,4% at 443 K and in 9 *** prepared catalysts were well characterized to investigate the effect on the catalytic performance and reaction catalysis *** experimental results show that the addition of La adjusted the structure and chemical properties of ZnAl composite oxide and that the synergistic effect among Zn,Al and La play a key role in adjusting the acid-base properties and stability of the catalyst,which definitely improved the DMC selectivity and catalytic *** on the proposed reaction mechanism,two kinetic models of the catalytic reaction were established and modified:LangmuirHinshelwood and power-rate law kinetic *** good agreement between kinetic models and experimental data showed that the power-rate law kinetic model based on the elementary reactions is a suitable model for providing a theoretical *** pre-exponential factor and activation energy of the main reaction are 5.77×10^(7)and 77.60 kJ·mol^(-1),respectively.

关键词： Methanol Urea alcoholysis dimethyl carbonate Kinetic model

Synthesis of dimethyl adipate from cyclopentanone and dimethyl carbonate over solid base catalysts

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Science China Chemistry 2012年第3期55卷 380-385页

作者： WU DuDu CHEN Zhi JIA ZhenBin SHUAI Li School of Pharmacy Guangdong Medical CollegeDongguan 523808China School of Pharmacy South Central University for NationalitiesWuhan 430074China

A facile route for the synthesis of dimethyl adipate （DAP） from cyclopentanone and dimethyl carbonate （DMC） in the pres- ence of solid base catalysts has been developed. It was found that the intermediate carbomethoxycyclopentanone （CMCP） was produced from cyclopentanone with DMC in the first step, and then CMCP was further converted to DAP by reacting with a methoxide group. The role of the basic catalysts can be mainly ascribed to the activation of cyclopentanone via the abstraction of a proton in the a-position by base sites, and solid bases with moderate strength, such as MgO, favor the formation of DAP.

关键词： dimethyl adipate cyclopentanone dimethyl carbonate solid base catalysts

One-pot Synthesis of dimethyl carbonate in the Presence of a Two-component Catalyst

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Chemical Research in Chinese Universities 2005年第6期21卷 714-717页

作者： CHEN Xiu-zhi HU Chang-wen GAO Zhi-ming The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 P. R. China Department of Chemistry Beijing Institute of Technology Beijing 100081 P. R. China

The one-pot synthesis of dimethyl carbonate（DMC） with co-production of propy-lene carbonate（PC） and propylene glycol（PG） from propylene oxide（ PO）, carbon dioxide and methanol as the starting materials was investigated. The catalyst adopted here was a mixture of tetrabutyl ammonium bromide and sodium methoxide. It was found that un- der the reaction conditions of t = 150 ℃, p =3-4 MPa and 2 h, the PO conversion could reach 100%, the DMC, PC and the PG selectivities were 49. 7%, 42. 7% and 49. 8%, respectively, and the selectivity of by-products was below 10%.

关键词： dimethyl carbonate Carbon dioxide Propylene oxide Propylene carbonate Catalyst

Influence of dehydrating agents on the oxidative carbonylation of methanol for dimethyl carbonate synthesis over a Cu/Y-zeolite catalyst

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1059-1063页

作者： Dong-Ho Lee Jiin You Je-Min Woo Jung Yoon Seo Young Cheol Park Jong-Seop Lee Hyunuk Kim Jong-Ho Moon Seung Bin Park Greenhouse Gas Laboratory Korea Institute of Energy Research Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology Energy Material Laboratory Korea Institute of Energy Research

The influence of the dehydration by metal oxides on the synthesis of dimethyl carbonate （DMC） via oxidative carbonylation of methanol was studied. A Cu/Y-zeolite catalyst was prepared by the ion exchange method from CuCl2.2H2O and the commercial NH4-form of the Y type zeolite, The catalyst was characterized by X-ray fluorescence （XRF）, N2 adsorption （BET method）, X-ray diffraction （XRD）, and temperature-programmed de- sorption of ammonia （NH3-TPD） to evaluate its Cu and Cl content, surface area, structure, and acidity. Reaction tests were carried out using an autoclave （batch reactor） for 18 h at 403 K and 5.5 MPa （2CH3OH ＋ 1/2O2 ＋ CO （CH3O）2CO ＋ H2O）. The influence of various dehydrating agents （ZnO, MgO, and CaO） was examined with the aim of increasing the methanol conversion （XMeOH, MeOH conversion）. The MeOH conversion increased upon addition of metal oxides in the order CaO 〉〉 MgO 〉 ZnO, with the DMC selectivity （SDMC） following the order MgO 〉 CaO 〉 ZnO. The catalysts and dehydrating agents were characterized before and after the oxidative carbonylation of methanol by thermogravimetric and differential thermogravimetric （TG/DTG）, and XRD to con- firm that the dehydration reaction occurred via the metal oxide （MO ＋ H2O →M（OH）2）. The MeOH conversion increased from 8.7% to 14.6% and DMC selectivity increased from 39.0% to 53.1%, when using the dehydrating azent CaO.

关键词： Carbon monoxide Zeolite Catalyst dimethyl carbonate Oxidative carbonylation Dehydrating agent

Macro kinetics for synthesis of dimethyl carbonate from urea and methanol on Zn-containing catalyst

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Journal of Central South University 2012年第1期19卷 85-92页

作者： ZHAO Wen-bo HAN Bing ZHAO Ning XIAO Fu-kui WEI Wei Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650224China Institute of Coal Chemistry Chinese Academy of SciencesTaiyuan 030001China

In a stainless steel autoclave,the synthesis kinetics of dimethyl carbonate(DMC) from urea and methanol was separately investigated without catalyst and with Zn-containing *** catalyst,for the first reaction of DMC synthesis(the reaction of urea with methanol to methyl carbamate(MC)),the reaction kinetics can be described as the first order with respect to the concentrations of both methanol and *** the second reaction of DMC synthesis(the reaction of MC with methanol to DMC),the results exhibit characteristics of zero-order *** Zn-containing catalyst,the first reaction is neglected in the kinetics model since its rate is much faster than the second *** macro-kinetic parameters of the second reaction are obtained by fitting the experimental data to a pseudo-homogenous model,in which a side reaction in forming process of DMC is incorporated since it decreases the yield of DMC drastically at high *** activation energy of the reaction from MC to DMC is 104 kJ/mol while that of the side reaction of DMC is 135 kJ/*** highest yield of DMC is 23%.

关键词： macro-kinetics dimethyl carbonate urea methanol methyl carbamate