Catalytic decarboxylation of fatty acids

Abstract

Biodiesel, defined as the mono-alkyl esters of vegetable oils or animal fats, is an environmentally attractive alternative to conventional petroleum diesel fuel, generally produced by transesterification with a monohydric alcohol, usually methanol. Biodiesel has many important technical advantages over petrodiesel, such as inherent lubricity, low toxicity, derivation from a renewable and domestic feedstock, superior flash point and biodegradability, negligible sulfur content, and lower exhaust emissions. However, important disadvantages of biodiesel include high feedstock cost, inferior storage and oxidative stability, lower volumetric energy content, inferior low-temperature operability. To overcome these problems, research is been focused mainly on the production of second generation biodiesel. They are produced through the process of decarboxylation including simple transformation of fatty acids into hydrocarbon based fuel. Second generation biodiesel contains almost all properties of a petro-diesel which simple biodiesel obtained by transesterification is lacking. In the present study, decarboxylation of short to long chain fatty acids were carried out using silver nitrate and lead acetate as a catalyst. Observations of the present study clearly indicate that catalytic efficiency of lead acetate is approximately similar to silver nitrate and shows a good correlation in between catalytic efficiency of both. The use of lead acetate, therefore, is being suggested as an effective alternative for decarboxylation of free fatty acids to produce second generation biodiesel.