NaOH-impregnated oyster shell as a solid base catalyst for transesterification of soybean oil

Abstract

There is significant interest in developing renewable solid base catalysts from agricultural wastes for use in the transesterification of fats into fatty acid methyl esters (FAME). In this study, an inexpensive base catalyst was synthesized by impregnating waste oyster shell with 50% sodium hydroxide solution, followed by calcination at 1000 ℃ for 3h. The resulting solid catalyst was used to catalyze transesterification of soybean oil. Transesterification using the catalyst was studied by systematically varying molar ratio (MR) (methanol to oil) and catalyst loading (CL). Results indicated that the highest FAME yield was 93.9% using MR of 12 and CL of 10%. Reusability tests suggested that the catalyst could be used for at least three runs without any significant decrease in FAME yield.