Experimental optimization and analysis of rice bran oil methyl ester

Abstract

The rapid growth and increasing aspirations of society, particularly in developing economies like India and China continue to drive demand for petroleum fuels. Limited resources of fossil fuels have led to higher prices of oil and natural gas in recent years. In a country like India, where we depend largely on oil imports, it is imperative that we accelerate our search for alternative sources of energy. Biofuels hold promise but require major R&D efforts. The main concern with biodiesel fuel is its high price. One of the future aims in biodiesel research is on the selection of inexpensive feedstock with high value added byproducts. Rice bran is a by-product of the rice milling process that contains 15-23 % lipids and a significant amount of nutraceutical compounds. Due to the presence of lipase in bran and the lack of economic stabilization methods, most bran is used as livestock feed or boiler fuel and most rice bran oil produced is not of edible grade. Thus rice bran oil is relatively an inexpensive raw material for production of biodiesel. Rice bran was sourced from small scale rice millers. The chemical composition of biodiesel was analyzed by GCMS test. The biodiesel was produced from rice bran through transesterification process using methanol as reagent and potassium hydroxide as catalyst. No pretreatment with an acid was necessary as the free fatty acid is below 3%. The concentration of catalyst was varied to identify optimum yield of biodiesel. The dependence of biodiesel yield on various parameters was theoretically predicted using MINITAB 17 software. The chemical composition of biodiesel was analyzed by GCMS test. The test result showed that the components of oil have converted into their corresponding methyl esters after transesterification. The performance test was conducted in four stroke single cylinder diesel engine using blends of biodiesel B5, B10, B20 and commercial diesel as fuel. The mechanical efficiency for B5 was better compared to other blends and diesel. The brake thermal efficiency was almost same for B5, B10, B20 but falls short of commercial diesel. The SFC was found to be least for diesel compared to blends. Thus rice bran oil biodiesel can be used as an alternate fossil fuel. It will go a long way in poverty reduction in line with the millennium development goals.