Improvement of low-temperature characteristics of biodiesel by additivation

In manipulation and utilization of biodiesel and its mixtures, especially in the winter period, one of the most serious problems is relatively poor low-temperature flow properties. Classic methods of transesterification solve this problem, so biodiesel quality can be improved only by additives (cold flow improvers). This research examines the effect of commercial additives on the improvement of low-temperature characteristics of biodiesel. Namely, cold filter plugging point (CFPP), pour point (PP) and cloud point (CP) were tested in accordance with EN 116 and ISO 3015 standards. The influence of additives on different types of biodiesel, its different age and influence on the mixture of 5 % biodiesel and fossil diesel were examined. A better effect of additivation to "fresh" biodiesel (made using rapeseed oil), compared to "aged" biodiesel was noted. Improvement of additivation was achieved by mixing additives with an organic solvent (toluene). It was demonstrated that different types of additives are suitable for different types of biodiesel as well as mixtures of biodiesel and fossil diesel. Additives in which solvent is compatible with the type of biodiesel were found to exhibit better performance. nema