Utilization of palm oil alkyl esters as an additive in ethanol-diesel and butanol-diesel blends

Abstract

Diesohol is a blend of diesel fuel, alcohol and an additive. The major impact of diesohol on engine performance is a significant reduction in visible smoke and particulate matter emissions. However, the major drawback in diesohol is that ethanol changes the fuel characteristics of the blend, especially by causing instability and reducing the cetane number. Therefore, this research focuses on the use of biodiesel as an additive in the diesohol preparation. Three types of Biodiesel-methyl, ethyl, and butyl esters-were prepared from palm oil through transesterification using a conventional base catalyst. Apart from ethanol, butanol is also another option to improve both solubility and fuel properties of the blends. Therefore, a comparative study of phase stability, the dependence of solubility on temperature (10, 20 and 30C), and an evaluation of some basic fuel properties according to ASTM of ethanol-diesel-biodiesel and butanol-diesel-biodiesel three-component systems at different component concentrations was done. We found that the use of butanol in diesohol could solve the problem of fuel instability at low temperatures because of its higher solubility in diesel fuel. In addition, the fuel properties results indicated that blends containing butanol have properties closer to diesel than those of blends containing ethanol.