Development and experimental investigation of a biodiesel from a nonedible woody plant: The Neem

The escalation of oil prices is irremediably accompanied by the rise of the prices of products of broad consummation and commodities. This results in a dramatic impoverishment of the neediest populations. This situation makes renewable energies like biodiesel a very attractive alternative to overcome the lack of fossil energy, because they respect the notion of sustainability and because of their ease of extraction. Because of its slight impact on food safety, Neem can be regarded as an adequate raw material to produce esters via an esterification process. The goal of this study is to extract oil from Neem fruits and to esterify it in order to obtain a biofuel. Then, the obtained product is tested within Direct Injection DI diesel conditions. The Neem Methyl Ester (NME) produced in the laboratory is then characterized according to different standards. It turns out that its chemical and physical characteristics, are close to that of classical esters of vegetable oils with acceptable lowest values. The output of the oil extraction is estimated at 27.5% and the Low Calorific Value (LCV) found is estimated to be 38.7 MJ/kg. The measure of opacity shows that chloride and potassium account respectively for 61.00 and 2.19 mol(-1) (thresholds values: 74.00 per mol). The principal pollutants such as CO, CO2 and unburned hydrocarbons are found to be at the lowest acceptable values. The biofuel elaborated has been tested thanks to a single cylinder (DI) diesel engine under the same burning conditions than those of petroleum based fuels. It has been observed that the performances of NME are acceptable compared to diesel fuel. The highest level of CO found for NME engine combustion mode is 698 mg/kg which is 18.83% less than mineral diesel. The Neem's NOx emission is 5.64% higher than that of diesel fuel at the same load condition. (C) 2015 Elsevier Ltd. All rights reserved.