Mixed Dicarboxylic Acid Dimethyl (h) Ester Synthesis Process

In this paper,we took a systemic study on esterification reaction of dicarboxylic acid with methanol and isooctanol.Via the characterization of raw materials qualitative and quantitative analysis,we designed and prepared a range of catalysts which contain zeolite, solid superacid and solid acid,and established a comprehensive evaluation system including the esterification reaction conversion rate and esterification product examination analysis and the catalyst response performance research technique,obtained the optimal reaction conditions of mixed dicarboxylic acid with methanol and isooctanol.We also studied product's operational performance.The experiment indicates that,with the sodium hydrogen sulfate monohydrate as catalyst,the optimized reaction conditions of the dibasic acid dimethyl esters were:mixed dibasic acids 0.1mol,n(mixed dibasic acids):n(methanol)=1:13,the catalyst 0.8g,refluxing and water segregating for 5.0h,The yield of the esters could reach 94.95%.The optimized reaction conditions of the dioctyl dicarboxylate were:mixed dibasic acids 0.1 mol,n(mixed dibasic acids):n(iso-Octanol)=1:2.7,reaction temperature is about from 108℃to 155℃,the amounts of dimethylbenzene is 15ml,the amounts of sodium bisulfate is 0.50g,and the conversion rate is 99.90%.when used the solid superacid for catalyst,the optimized reaction conditions of the dibasic acid dimethyl esters were:mixed dibasic acids 0.1mol,n(mixed dibasic acids):n(methanol)=1:12,the catalyst 0.3g,refluxing and water segregating for 4.0h,The yield of the esters could reach 94.60%.The optimized reaction conditions of the dioctyl dicarboxylate were:mixed dibasic acids 0.1mol,n(mixed dibasic acids):n(iso-Octanol)=1:3.4,the reaction temperature is about from 160℃to 220℃,the reaction time is 4h,the amounts of catalyst is 0.30g,and the conversion rate is 99.91%.The optimal reaction conditions of sodium bisulfate catalysis synthesis dioctyl dicarboxylate are that theThe product is characterized by MS.Simultaneity,the physical properties of target product is measured by boiling point,acid value,ester content and so on.