Esterification of methacrylic acid with ethylene glycol over heteropolyacid supported on ZSM-5

Abstract

Esterification of methacrylic acid with ethylene glycol was carried out over Heteropolyacids [HPA: H4SiW12O40 (STA) and H3PW12O40 (PTA)] supported on ZSM-5. For comparison, the same reaction was carried out over unsupported HPA, H 2SO4, BF3 and PTSA. Among the catalysts studied, HPA showed better activity compared to H2SO4, BF3 and PTSA. Catalytic activity was compared with HPA supported ZSM-5 catalysts. Typical results indicated that 30 wt% PTA supported on ZSM-5 showed nearly the same activity as that of bulk PTA. It was found that the reaction follows first order kinetics with respect to methacrylic acid. The reaction products were identified by 1H-NMR and FT-IR.