The Research On The Preparation Of Fumaric Acid From Maleic Acid Catalysed By Metalloporphyrins

Fumaric acid also known as trans-butenedioic acid,is taken as a kind of four carbon binary carboxylic acid,meanwhile,it is a kind of important chemical intermediates.As fumaric acid is widely used in different areas,especially as an important platform for the four carbon compounds,its application is paid more and more attention.There are two main methods to prepare fumaric acid:chemical synthesis and biosynthesis method.This article used chemical synthesis to prepare fumaric acid,we mainly used maleic acid as reaction substrate,metalloporphyrin or immobilized metalloporphyrins as catalyst,then we studied the different reaction conditions on the maleic acid C=C double bond cis-trans isomerization on preparation of fumaric acid,the influence of the main contents are as follows:(1)the catalyst preparation.This article first mainly introduced the synthesis of tetraphenylporphyrin was prepared with both benzaldehyde and pyrrole as raw material and propionic acid as solvent,then we used tetraphenylporphyrin as raw materials and DMF as solvent with different metal salts to synthese different center single metalloporphyrin catalysts.Meanwhile,the synthesis way of the supported metalloporphyrin is also introduced,which included two kinds of immobilized metalloporphyrin respectively mesoporous SBA-15 immobilized manganese porphyrins and imidazole-modified chloropropyl functionalized SBA-15 immobilized manganese p orphyrins.(2)catalyst characterization.Tetraphenylporphyrin and metalloporphyrin was mainly characterized by UV-vis,FT-IR and TOF.Characterization and analysis showed that the synthesis of tetraphenylporphyrin and metalloporphyrin was successed.Two kinds of immobilized metalloporphyrins was mainly characterized by UV-vis,FT-IR,low angle XRD,N2 adsoption-desoption,TG and ICP.Characterization and analysis showed that fixed load variation of two kinds supported metalloporphyrin and metalloporphyrin carrier crystal,the structure of the channel,thermal stability changes before and after fixed load.(3)the catalytic experiment.This work contained homogeneous catalysis and heterogeneous catalysis,as two perspective of cis-trans isomerization of maleic acid to fumaric acid.Homogeneous catalysis was under atmospheric pressure conditions、oxygen atmosphere and MnTPPCl as catalyst,reaction conditions to the effects of maleic acid cis-trans isomerization conversion was taken into consideration such as reaction temperature,reaction time,catalyst dosage,oxygen flow and got the best reaction condition,at the some time,we also examined the different center of metalloporphyrin to maleic acid cis-trans isomerization,and we had made the preliminary elaboration to interpret the reaction mechanism.Research process of heterogeneous catalysis similar to homogeneous catalyst,reaction catalysts are both manganese porphyrins immoblized on SBA-15 and manganese porphyrins supported on imidazole-modified chloropropyl functionalized SBA-15 solid,and oxygen atmosphere under the atmospheric pressure condition,respectively for the immobilized catalysts,the influence of reaction conditions such as reaction temperature,reaction time,catalyst dosage,oxygen flow affected maleic acid cis-trans isomerization conversion rate,we could got the corresponding optimal reaction conditions for two catalysts.