A REVIEW OF GLOBAL SCENARIO OF BIODIESEL, SOURCES AND SLUDGE PALM OIL WASTE FOR THE BIODIESEL PRODUCTION

Abstract

The uncontrolled usage of fossil fuel and its by-products has largely contributed to global warming which is by far irreversible; these non-renewable reserves if exhausted might have a major impact on human development. This urges the need of discovering a sustainable renewable energy source which could potentially replace the fossil fuel in future, this is also the main focus researchers working on field of energy. A more sustainable biodiesel, which also is biodegradable and a clean energy has drawn a significant amount of attention and interest across the globe in recent years. Steady raise in the price of petroleum products and importantly the environmental concerns, highlighted the need of alternative fuels. Biodiesel primarily consists of Fatty Acid Methyl Esters (FAME), which are derived through transesterification of various sources such as vegetable oils, animal fat etc. In addition, the recycled oil from the food industry when processed with a suitable catalyst along with methanol produces mono alkyl esters, which are further segregated and purified. Bio-diesel can be produced through many techniques including acid & base catalysis, enzymatic conversion, solid catalysis, non-catalytic conversion and super-critical methanolysis. Multiple factors such as, amount of alcohol, catalysts and reaction temperature, reaction time and FFA and water content of oils or fats impact the transesterification reaction. The multiple advantages of Biodiesel include safety, non-toxicity and biodegradable in comparison with petroleum based products, thus justifying its title as “Green fuel”. The reduced polluting ability of Biofuels is due to the fact that they are oxygenated and are relatively free of sulfur and other aromatic compounds, thus being a effective fuel with reduced emission of Sulfuric oxides, Carbon monoxide, residual hydrocarbons and particulate matter. Thus no engine modification is required with the prior blending proportion with normal petroleum diesel. The major physicochemical properties are similar between biodiesel and the petroleum fuel. The present review made an attempt to cover the scenario of worldwide concerned towards biodiesel production, its scope and need, various sources adopted for biodiesel preparation, the various catalysts, reaction condition adopted, maintained during production of biodiesel and its fuel properties (depends on Free Fatty Acid profile of the feedstock) and an exclusive role of Sludge Palm Oil (SPO) form palm oil processing industries, a cost effective feedstock for biodiesel preparation.