Biodiesel Production Using Solid Catalyst

Abstract

Biodiesel is a cleaner burning fuel than diesel and suitable replacement. It is made from non-toxic, biodegradable, renewable resources, such as vegetable oil and animal fats. Fats and oils are chemically reacted with alcohols to produce chemical compound known as fatty acid methyl esters (Biodiesel). Glycerol, used in the pharmaceuticals and cosmetics industry along with many other applications, is produced in this reaction as a by-product. Jatropha oil which has no economically significant use and hence can be come an ideal raw material for the manufacture of Biodiesel. Currently, nearly all biodiesel is produced via homogeneous catalysis. The use of homogeneous catalysts allows carrying out the transesterification of lipid feedstock with small alcohols under mild conditions. However, the advantage of having a production process at low temperatures is most likely counteracted by the additional separation procedures the products require. Residual catalyst must be removed and catalyst loss is inherent, raising the overall cost of production. In contrast, processes using heterogeneous catalysts need higher temperatures to be as effective in a reasonable time. On the other hand, products do not necessitate complex separation procedures and in most cases, catalysts can be recycled and reused for long periods of time Heterogeneous catalysts offer exciting possibilities for improving the economics of biodiesel synthesis. In this work, Extraction of oil from jatropha seed kernels was done by three phase partitioning method. Effect of sonication on oil yield was also studied. In this method 80 % of oil was extracted from jatopha seed kernels. By applying sonication for 5 min 85 % of oil was extracted. Transesterification of jatropha oil with methanol has been studied in a heterogeneous system, using alumina loaded with potassium nitrate as a solid base catalyst. After loading KNO3 of 35 wt. % on alumina followed by calcination at 773K for 4 h, the catalyst gave the highest basicity and the best catalytic activity for this reaction. Moreover, the dependence of the conversion of jatropha oil on the reaction variables such as the catalyst loading, the molar ratio -iii- ivof methanol to oil, reaction temperature, agitation speed and the reaction time was studied. The conversion was over 84% under the conditions of 70°C, methanol/oil mole ratio of 12:1, reaction time 6 h , agitation speed 600 rpm and catalyst amount (catalyst/oil) of 6% (w). Kinetic study of biodiesel production method was done. Properties of Jatropha oil, biodiesel and its blend with diesel was found out. Besides, catalyst reusability study was also done.