Catalytic Cracking of Triglyceride by Sulphated Zirconia for Fatty Acid Methyl Ester with High Selectivity

Abstract

Conventional wet-precipitation method was used to synthesis sulphated zirconia using two different molar ratios of sulphating agents. (1) the first was using a molar ratio of 1: 45 of ZrOCh.8H₂O impregnated with 1 M H₂SO.. (wp) and (2) a molar ratio of 1: 6 was used for the modified conventional wet-precipitation method, (mwp). The properties of both catalysts were examined by various techniques: EDX, XPS, FTIR, SEM, XRDP, Py-DRIFTS and BET nitrogen adsorption techniques. The variation in the molar ratio of the sulphating agent used during preparation led to sulphated zirconias that exhibited different in terms of specific surface areas, acid sites, thermal stability and surface sulphate. Both catalysts were catalytically active for triglycerides racking for fatty acid methyl esters in a thermocatalytic reaction. The SZI not only exhibited higher conversion of triglycerides but higher FAMES yield, approximately 50% after 3 h, as compared to SZ2 (39%). Interestingly, SZI was selective towards unsaturated esters whereas SZ2 was towards saturated esters