Quantitative study on production of methyl ester (biodiesel) from castrol oil and nannochloropsis salina (microalgae)

Abstract

Due to the awareness of adverse effects of conventional fuels to environment and the frequent rise in crude oil’s price, the need for sustainable and environment friendly alternate source of energy has grown manifold in recent years. Biodiesel is proved to be the best replacement for diesel because of its unique properties like significant reduction in green house gas emissions, non-sulfur emissions, non-particulate matter pollutants, low toxicity. The most widely used feedstocks for biodiesel production were vegetable oils. But beside this traditional feedstock, microalgae is also of growing interest as a potential feedstock for biodiesel production due to its high lipid content when cultured under certain environment. In this work, biodiesel has been produced from Castor oil and Nannochloropsis Salina. The Castor oil methyl ester production has been optimized at 93.6% yield at catalyst concentration 1.5%, alcohol to oil ratio 6:1 (mol/mol), at 55^oC for 120 minutes of reaction time. The lipid content from Nannochloropsis has been extracted and converted into methyl ester using Soxhlet extraction (using two different solvents- n-hexane and chloroform and methanol mixture) followed by transesterification and using microwave assisted in-situ transesterification. The highest biodiesel from microalgae is 20% on dry weight basis. The results showed that the production of methyl ester from Castor oil is more compared to Nannochloropsis Salina methyl ester and therefore it was concluded that Castor Oil methyl ester is a better choice for diesel blending.