Kinetics and mechanism of maleic acid hydroxylation by hydrogen peroxide. Part I: Formal kinetic studies by immobilized catalysis in a pseudo‐homogeneous system

Abstract

AbstractFormal kinetic studies of the epoxidation and hydroxylation of maleic acid by hydrogen peroxide (H2O2) have been carried out in the presence of a molybdenum salt, as catalyst, immobilized on Amberlite IRA‐400 polymer resin in the chloride form. Immobilization of the catalyst on the resin was by a sorption process. Hydroxylation by immobilized catalysis afforded higher H2O2 selectivity and increased product yield in excess of 85%. Analysis of kinetic results shows that the reaction in the pseudo‐homogeneous system follows the typical pseudo‐zero order dependence on H2O2 concentration and is first order with respect to maleic acid concentration. However, the rate model developed for the immobilized catalyst fits the experimental data smoothly and parameter estimation using the Lineweaver–Burk plot fulfils the kinetic consistency tests without additional mathematical manipulation. The problem of activity and stability of the present catalyst was also investigated.