TRANSESTERIFICATION OF GLYCEROL WITH METHYL ACETATE OVER TUNGSTOPHOSPHORIC ACID

Abstract

Transesterification of glycerol with methyl acetate was carried out in the presence of tungstophosphoric acid immobilized on silica. Tugnstophosphoric acid was immobilized by sol–gel technique on silica. A series of PW immobilized on silica with different PW loadings from 2.5 wt.% to 6.5 wt.% were prepared. It was observed that the PW2-S (with 4.2 wt.%) shows the highest catalytic activity on transesterification of glycerol with methyl acetate. Catalytic stability of the PW2-S was evaluated by performing consecutive batch runs with the same catalyst sample. After the second batch it was observed a stabilisation of the initial activity. A kinetic model was developed assuming that the glycerol is consumed according to the successive reaction network. Since the concentration profiles of the reagent and the products do not exhibit any pronounced initial inductive period, the external and internal diffusion of the reagents and products on the catalyst were not considered. It was observed that the kinetic model fits experimental concentration data quite well.