Supported Catalyst Synthesis Maleic Acid Diester And Preparation Of Fumaric Acid By Paired Electrolysis

Maleic acid is an important four-carbon platform Compound,common derivatives like maleic acid diester,tartaric acid,fumaric acid,succinic acid,DL-malic acid,etc.Maleic acid diester as an important class of unsaturated carboxylic acid ester have important uses in Pigment / paint fixing agent,fibers,dispersants,synthetic plastics,paper industry,petrochemical industry and other aspects.Fumaric acid and derivatives are widely used in food preservative,seasoning,feed,Chemical and plasticizers and other fields for their non-toxic,low corrosivity,and can also synthesis of a series of compounds.We take maleic anhydride reacted with n-butanol maleate butanol as a probe reaction to study supported catalysts' effect on Esterification.Respectively discussed the effects of preparation conditions of supported catalyst,amount of catalyst,reaction time,temperature,water carrier type and amount,and repeated use of catalyst on the esterification rate.characterize the product structure.And investigate the application of Supported catalyst in synthesis of Maleic acid diester.By finding optimal conditions: when the amount of maleic anhydride 0.1mol,silicon dioxide as a carrier,supported phosphotungstic acid catalyst calcined at 400 ? 2h,anhydride alcohol molar ratio of 1: 3,the amount of catalyst 8.2%,with the amount of benzene agent as 6mL,reaction 4h,esterification rate of 96%,an ester yield of up to 84%,Recycle reuse catalyst for three times and the esterification rate is still more than 91%.used the catalyst for other synthetic test can also work well.Prepare Fumaric acid by paired electrolysis Method.Respectively discussed the effects of electrolysis,electrode materials,ion membrane type,electrolysis time,temperature,amount of catalyst,the current density and other factors on Fumaric acid Yield,And analysis product by high performance liquid chromatography.Take small scale test with 2L electrolyzer made by laboratory.Discussion on the influencing factors of amplification experiment to provide reference for large-scale experiments and Simulation of industrialization.It was found that at the anode by electrolysis bathcatalytically converted to maleic acid,fumaric acid configuration is feasible.Under conditions of electrolysis at constant voltage constant current power supply constant current,electrolytic platinum plate electrode,the cation exchange resin as the ion-exchange membrane,catalyst dosage 2%,0.1mol / L 5% of the amount of supporting electrolyte,current density of 204 A / m2,electrolysis temperature 0-10 ?,electrolytic 3h,fumaric acid yield of 82%.Further,in the cathode cell to obtain succinic acid product yield of 87%.Small scale test,using a platinum-plated titanium plate as an anode and a titanium plate as a cathode catalyst 2%,supporting electrolyte concentration 0.08 mol / L,the current density of 200 A / m2,electrolysis 4h,electrolysis efficiency up to 67%.