Volatility of Biodiesel Obtained from Rapeseed Blends with Petroleum Diesel

The volatility has been studied since it influences the ignition quality of the fuels in a compression ignition engine. The chemical composition of -10# petrodiesel (-10PD) and rapeseed biodiesel (RME) was analyzed by gas chromatography-mass spectrometry (GC-MS). Volatility of -10PD and RME. was studied by thermogravimetry (TG) and liquid volatile theory. Volatile index V was put forward for describing -10PD/RME volatility. A good correlation model was proposed for calculate the -10PD/RME volatility by RME blending ratio. The study showed that -10PD was mainly composed of alkanes: C8-C26. RME was mainly composed of saturated fatty acid methyl esters (SFAME): C14:0-C24:0, unsaturated fatty acid methyl esters (UFAME): C16:1-C22:1, C18:2 and C18:3. The mass fraction of SFAME and UFAME was 14.69% and 83.40%, respectively. RME is considerably more volatile in comparison to -10PD. The -10PD/RME volatility has relation to RME blending ratio. The volatility of B0-B20 is very close to -10PD. The volatility of B20-B100 is better with increasing the RME blending ratio.