Esterificação do ácido oleico com butanol utilizando diferentes catalisadores ácidos

Abstract

With the increase of the oil prices and the many environmental problems like Global Warming, the shift from fossil raw materials to renewable resources is crucial to a sustainable future. Researches are underway to find alternatives that effectively replace non-renewable energy sources. Plant-derived oils have a strong potential for replacing petrochemicals. Biolubricant has been shown to be a good substitute for mineral lubricant, a petroleum derivative, as it has low pollutant emissions, less toxicity, because it is of renewable origin and because it is biodegradable, causing less environmental impact. A good lubricant features: reduced loss of mechanical energy, reduced wear of components subject to friction, corrosion protection of equipment components, and reduced operating temperature of machines, among other characteristics. The esterification reactions of free fatty acids (FFAs) are being widely studied due to the need to improve the physical and chemical characteristics of biofuels and biolubricants. This work sought to convert oleic acid into butyl oleate through the esterification reaction of FFA with butanol, using two acid catalysts and comparing the effectiveness of each along with the determination of the best, and most viable, reaction conditions used to obtain a lubricating base. Through the alkaline titration technique, it was possible to obtain the conversion value of each esterification, and thus determine the reaction that presented the best yield, as well as evaluates the influence of temperature, time and amount of catalyst used for this reaction. The reactions were shown to be time and temperature-dependent, where even using the 9:1 molar ratio the % conversion was low at temperatures of 80 °C in times of 8 hours. The best conversion value was 97.1%, obtained in a 9:1 molar ratio of butanol and oleic acid, respectively, in 8 h of reaction, with 2% APTS at 80 ºC.