Production of biodiesel from soybean oil using Li4SiO4 as a heterogeneous catalyst

摘要

This study synthesized biodiesel from soybean oil using transcsterification over a lithium orthosilicate (Li4SiO4) catalyst. Under the optimal reaction condition of a methanol/oil molar ratio of 18:1, a 4 % (wt/wt oil) catalyst amount, and a reaction at 65°C for 2 h, the conversion to biodiesel could achieve 93.3 %. Prepared using a solid-state reaction, the Li4SiO4 can be directly used for biodiesel production without being further dried or thermal pretreated, avoiding the usual activation of solid catalysts at high temperature, The effects of the methanol/oil ratio, catalyst amounts, reaction time and reaction temperature on the conversion were also examined and are reported in this paper. The solid base catalyst was highly active, air-insensitive and can be reused for at least ten cycles without loss of activity. The catalysts were characterized by means of XRD (X-Ray Diffraction), and Hammett indicator method.