Biodiesel from Neem oil as an alternative fuel for Diesel engine

In the current energy scene of fossil fuel, renewable energy sources such as biodiesel, bioethanol, biomethane, and biomass from wastes or hydrogen have become the subjects of great interest. These fuels contribute to the reduction of dependence on fossil fuels. In addition, energy sources such as these could partially replace the use of those fuels which are responsible for environmental pollution and may be scarce in the future. For these reasons they are known as "alternative fuels". Vegetable oil cannot be directly used in the diesel engine for its high viscosity, high density, high flash point and lower calorific value. So it needs to be converted into biodiesel to make it consistent with fuel properties of diesel. Biodiesel production is a valuable process which needs a continued study and optimization process. The present study was intended to consider aspects related to the production of biodiesel from Neem oil and investigating its fuel properties. The seeds of Neem contain 30-40 % oil. This report deals with biodiesel obtained from Neem oil which are mono alkyl esters produced using 'Transesterification' process. The optimum conditions to achieve maximum yield of biodiesel were investigated at different temperatures and with different molar ratio of Neem oil and methanol. The most expected result including layer of glycerin and soap has been investigated at 3: 1 molar ratio of methanol and Neem oil at 55 to 61 degrees C temperature ranges. It was apparent that the fuel properties of biodiesel including density, kinematic viscosity and calorific value lie within the standards biodiesel properties especially (ASTM 6751-02) recommended standard of kinematic viscosity lies between 1.90 to 6.0 centistokes. Biodiesel can make a major contribution in the future if it meets the few percent of petroleum and it can provide improved fuel properties lower emission of unburned hydrocarbons, carbon monoxide but higher level of oxides of nitrogen. (C) 2013 The Authors. Published by Elsevier Ltd.