The Effect of Fatty Acid Composition on Combustion Characteristics of Vegetable Oils

Abstract

Vegetable oil is triglyceride molecules consisting of glycerol with three carbon chains as the backbone and three branches of fatty acids. Fatty acid molecules contain carboxylic acid and methyl ester (biodiesel). The properties of methyl esters from vegetable oils are almost similar to those of diesel oil. Therefore, fatty acids are a good potential source for diesel oil. This study aims to elucidate the effect of fatty acid composition on the combustion characteristics of vegetable oil. In this study, the combustion characteristics of the oil were observed experimentally by burning a single droplet on a heated stainless-steel plate. The results show that vegetable oil is burned in three stages: burning unsaturated fatty acids, saturated fatty acids, and glycerol at the first, second, and third stages, respectively. Compared to ceiba pentandra, cotton, and coconut oils, the combustion characteristics of jatropha curcas linn oil resemble most of the diesel oil. The burning of ceiba pentandra oil has two small explosions, while jatropha curcas linn, cottonseed, and diesel oils have only one small explosion, and no explosion occurs during the coconut oil burning. Unsaturated fatty acids and glycerol are highly explosive. The burning rate of the vegetable oil droplet is influenced by the flashpoints, fatty acid content, and dissociation energy of fatty acid bonds. The larger the number of the unsaturated fatty acid component, the higher the burning rate of the oil.