Epoxidation of allyl chloride with hydrogen peroxide catalyzed by titanium silicalite 1

Abstract

In this paper, different parameters affecting the epoxidation of allyl chloride with hydrogen peroxide, as well as the kinetic characteristics are described. The influence of the amount of catalyst and the concentration of oxidant and substrate, the effect of solvent and additive have been investigated. The epoxidation of allyl chloride is first order with respect to the amount of catalyst and between zero and unity order in the substrate and oxidant concentration. The epoxidation was accelerated and the selectivity was improved with increasing the concentration of substrate and the amount of TS-1. Finally, a possible kinetic model was supposed according to Eley-Rideal isotherms, which was in agreement with experimental data. Both the weak acidity of TS-1 surface and the proton produced by the interaction of active sites of TS-1 with hydrogen peroxide can catalyze the solvolysis of oxirane product. The best solvent for epoxidation of allyl chloride is methanol or methanol/water mixture. Small amount of additives can affect the reaction seriously. Inorganic basic compounds and fluorides can suppress the epoxidation completely, while acidic materials can promote the solvolysis of product.