High oleic safflower oil as a feedstock for stable biodiesel and biolubricant production

Abstract

Biodiesel and other derivative compounds which could act as biolubricants, can be a suitable alternative for petroleum products, which are less sustainable and harmful to the environment. However, especially when vegetable oils are used as raw materials (for instance Carthamus Tinctorius), these products can show poor oxidative stabilities, depending on their fatty acid composition. Apart from adding antioxidants as additives, a good alternative might be the use of genetically modified seeds to facilitate high ratios of stable fatty acids like oleic acid. The aim of this work was to produce biodiesel and biolubricant from high oleic safflower through transesterification with methanol and 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, respectively. The efficiency of these processes and the quality characterization of biodiesel and biolubricant were assessed. As a result, the biodiesel obtained (HOSBD) complied with the standard, with a high oxidative stability value (8.2 h) and not requiring any antioxidant addition. The biolubricant obtained (HOSBL) showed higher oxidative stability (6.72 h) compared to their equivalents produced from rapeseed (Brassica Napus) or cardoon (Cynara Cardunculus L.). Consequently, two stable bioproducts were obtained and the role of fatty acid composition of raw material was vital (oleic/linoleic ratio had a strong influence on oxidative stability). In that sense, the use of stable raw materials like high oleic safflower might avoid antioxidant addition in biodiesel or biolubricants, which implies a cleaner and more sustainable production.