Performance of Tetraphenylsulfonato Disilane in Catalytic Transesterification of Crude Palm Oil and Esterification of Fatty Acids with Secondary Alcohols

Abstract

1,2-dimethyl-1,1,2,2-tetraphenylsulfonato disilane (DMTPS) has been prepared by sulfonation of 1,2–dimethyl–1,1,2,2–tetraphenyl disilane and its catalytic activities in transesterification of palm oil and esterification of fatty acids with secondary alcohols have been studied. The DMTPS was characterized by FT–IR, 1H–NMR and 13 C–NMR and showed that all phenyl rings have been sulfonated. The transesterification of crude palm oil with methanol using DMTPS as the catalyst performed in an autoclave under a temperature ranging from 120°C to 160°C. The total ester yielded from transesterification was 96%. Then, the catalyst was recovered (97%) and reused in three other successive transesterifications at 160°C to see the catalyst activity and stability. It was found that the catalyst activities remain unchanged shown from the transesterification yield which was 96% in each reaction. The FT–IR of the used DMTPS catalyst was also very similar to that of the original one. The DMTPS catalyst also used in the esterification of long chain fatty acids with two secondary alcohols i.e. 2–propanol and 2–butanol at 150°C, provided yield of 86% and 48% of esters respectively. These show that the DMTPS catalyst is a stable catalyst in moderate temperature and show a good performance in both transesterification and esterification involving secondary alcohols.