Chemical Modification of Oleic Acid Oil for Biolubricant Industrial Applications

There has been a lot of interest in using vegetable oils as renewable raw materials for new industrial products including lubricants. This emphasis on environmentally friendly lubricants is largely due to the rapid depletion of world fossil fuel reserves and increasing concern for environmental pollution from excessive mineral oil use. Vegetable oils are promising candidates as base fluid for ecofriendly lubricants, but their use is restricted due to low thermo-oxidative stability and poor cold flow behavior. This paper presents use chemically modified triesters derived from oleic acid to improve the oxidation and cold flow behavior. Here, we report the oxirane ring opening of epoxidized oleic acid using behenic acid and />-toluenesulfonic acid (PTSA) as catalyst followed by esterification reaction with octanol and 2-ethylhexanol to form diesters (compounds 3 and 4), respectively. The remaining free hydroxyl group was reacted with oleic and stearic acid to give triesters (compounds 5 and 6), respectively. One of the products, compound 6, was shown to have pour point, flash point and viscosity indices of -60 °C, 305 °C, and 193 cp, respectively, which are favourable properties in biolubricant applications. The structures of the products were confirmed by FTIR, ʹH- and 13C-NMR