Determination of carbon microresidue at mixtures of diesel/biodiesel

Abstract

This study proposes to evaluate the influence of the addition of biodiesel to diesel in relation the combustion quality of Diesel/Biodiesel mixtures by monitoring the carbon residue. Biodiesel methyl and ethyl esters were synthesized from soybean oil using KOH as catalyst. The diesel and the methyl and ethyl esters were characterized according to official methods. The mixtures were obtained in proportions of 5 %, 10 %, 15 %, 20% and 25% of biodiesel in diesel and were evaluated by analyzes of microresidue carbon, higher heating value and kinematic viscosity. The results show an increase of the carbon residue with the content of biodiesel and also with the increase of the chain of the methyl ester (biodiesel methyl to ethyl biodiesel) which may indicate a greater possibility of carbon residue deposits in the injection system and the engine pistons.