Study On The Transesterification Process Of Dimethyl Carbonate And Alcohols Catalyzed By Solid Base

Dimethyl carbonate(DMC)can be widely used in methylation,carbonylation,methoxylation,transesterification and other organic chemical reactions.Among them,DMC and alkyl alcohols or bio-based furan alcohols through the ester exchange reaction to synthesize other carbonate ester products are widely used in diesel fuel anti-wear agent,lithium battery electrolyte,lubricant base oil,resin plasticizer,pesticides and pharmaceutical intermediates and other industries.The raw materials can be derived from cheap and renewable biomass resources,with the advantages of clean,environmentally friendly,pollution-free production process.Since the ester exchange reaction is a typical reversible reaction,the efficiency of the current production process is low due to the limitation of thermodynamic equilibrium.In this work,the solid base catalyst independently developed by the research group and scaled up to industrial production was selected to study the transesterification reaction process of dimethyl carbonate and alcohol compounds,focusing on the reaction degree and process conditions of dimethyl carbonate and alcohol compounds in batch reactor and catalytic distillation integration reactor.It provides some theoretical guidance for the development and industrial production of downstream products of DMC.The main research contents and results are as follows:Through the thermodynamic analysis of transesterification reaction between DMC and series alcohols and comparative experimental study of batch kettle reaction,We Know that from low carbon alcohols to high carbon alcohols,straight chain alcohols to branched alcohols,the transesterification reaction in the forward direction becomes more difficult and less efficient.Aspen Plus software was used to simulate and analyze the thermodynamic data of transesterification reaction between dimethyl carbonate and alcohols,which provided some theoretical guidance for the downstream product synthesis and process exploration of dimethyl carbonate.DMC and furfuryl alcohol ester exchange reaction successfully synthesized a new bio-based diesel fuel antiwear agent "difurfuryl carbonate",its kinematic viscosity is 21.5mm~2 / s(40 ℃),pour point-25 ℃,freezing point-28 ℃,Acid value 5～10 mg KOH/g,cetane number 96,calorific value 39.2,are in line with the diesel fuel antiwear agent use standards.At the same time,it is expected to solve the problem of high acid(Acid value: 185～200mg KOH/g,GB/T7304)value of sour diesel fuel antiwear agent which leads to equipment corrosion,and has good application prospects.The integrated process study of forward and reverse catalytic distillation of DMC and ethylene glycol ester exchange reaction was studied.Through the optimization of process conditions,the conversion rate of forward reaction raw material and the yield of product were more than 95%;the reverse reaction process study was carried out in the same experimental equipment,under the optimal process conditions,the feedstock conversion and product yield reached more than 90%.Compared with the results of intermittent kettle reaction(positive reaction product yield: 42.37%,reverse reaction product yield: 75.07%),the product yield was greatly improved.To design pilot synthesis process of electronic grade dimethyl carbonate catalytic rectification,mainly including pilot process flow design,main equipment design,whole process material and energy balance,environmental and safety analysis,and economic benefit analysis.