Study of oxidative stability and cold flow properties of Citrillus colocynthis oil and Camelus dromedaries fat biodiesel blends

Biodiesel prepared from animal fat has been gaining increasing interest in the last few years. The main drawback of biodiesel is its poor low-temperature performance, which limits its use in cold climates. This study proposes a method of improving the low-temperature properties of young Camelus dromedaries (Hachi) fat biodiesel (HB) and improving select fuel properties [e.g., the cetane number (CN) and oxidative stability (OS)] of Citrullus colocynthis biodiesel (CCB), which has a high iodine value (IV). HB and CCB were blended in different volume ratios (100:0; 80:20; 60:40; 40:60; 20:80, and 0:100) and the fatty acid methyl ester (FAME) composition and fuel properties of the biodiesel blends were evaluated according to the American Society for Testing and Materials (ASTM) methods The correlation of the cloud point (CP), pour point (PP), cold filter plugging point (CFPP), kinematic viscosity (KV), CN, IV, and OS with the ratio of saturated to unsaturated FAMEs was determined. HB improved all the studied fuel parameters of CCB, and the international standards (ASTM D-6751 and EN 14214) were met. It is shown that the fuel properties of the biodiesel blends can be predicted using the FAME composition. The results of our study demonstrate that blending the biodiesel from Hachi fat and C. colocynthis seed oil provides a suitable alternative to biodiesel prepared using food crops.