Inorganic‐organic hybrid material based on amine‐functionalized zeolite Y: A study of catalytic activity in transesterification

Abstract

Three different structures of amine compound, 3‐aminopropyl trimethoxysilane (N1), N‐[3‐(trimethoxysilyl)propyl] ethylenediamine (N2), and N‐[3‐(trimethoxysilyl)propyl] diethylenetriamine (N3), functionalized on zeolite Y, were used to enhance catalyst lifetime in the transesterification reaction. The presence of amine compound was confirmed by FTIR. Moreover, the grafting percentage of amine on zeolite Y was also considered, since it affected the basicity and basic strength of the catalyst. The catalytic activity testing for transesterification of glyceryl tributyrate (GTB) and methanol was carried out in an autoclave reactor at reaction conditions of 30:1 molar ratio of methanol to GTB and a catalyst loading level of 0.35 g/g (35 mass% of GTB). The highest methyl butyrate production per active site was obtained by N3, due to its having the highest basic strength. The highest methyl butyrate yield was given by N1, due to its having the highest amino group concentration (basicity). Therefore, the catalytic activity, in terms of methyl butyrate yield and methyl butyrate production per active site, was affected by both basic strength and basicity. The reusability of the catalysts showed that the methyl butyrate yield slightly declined to ∼13.8 % yield after four cycles, but the methyl butyrate production per active site remained constant across four cycles.