KINETICS OF TRANSESTERIFICATION OF VEGETABLE OILS FOR THE PRODUCTION OF BIODIESEL

Abstract

Efforts are under way in many countries, including India, to search for suitable alternative diesel fuels that are environment friendly. The need to search for these alternatives arises mainly from the standpoint of preserving the global environment and conserving long-term supplies of conventional hydrocarbon-based diesel fuels. Among the different possible sources, diesel fuel derived from triglyceridees (vegetable oils/animal fats), known as biodiesel, present a promising alternative to substitute diesel fuels in conventional diesel engines. Although triglycerides can be directly used in diesel engines, their high viscosities, low volatilities and poor cold flow properties have led to the investigation of various derivatives of vegetable oils. Fatty acid methyl esters, known as biodiesel, derived from triglycerides by transesterification with methanol/ethanol has received the most attention. But main problem in this process is its batch application. It is very necessary to make a process continuous for large production. For a continuous process, there is need to design a continuous reactor and it needs kinetics of reaction. In this study, efforts has been made to find out the kinetics of transesterification reaction for biodiesel production from cottonseed oil and pongamia oil. Result of the study shows that reaction constant increases with increase in temperature and molar ratio, optimum condition for both the oils are 70 °C & 6:1 molar ratio. The main advantages of using biodiesel are its renewability, better quality exhaust gas emissions, its biodegradability and given that all the organic carbon present is iii photosynthesis in origin, it does not contribute to a rise in the level of carbon dioxide in the atmosphere and consequently to the greenhouse effect.