Study of enzymatic production of biodiesel using vegetable oils and commercial ethanol

Abstract

Biodiesel is a combination of alkyl fatty acid esters generated by a catalyst and supported by acid, basic, or enzymatic processes from vegetable oils to short-chain alcohols such as methanol or ethanol. However, the high costs for raw materials utilising vegetable oil of food grade have made it commercially impracticable to produce this biofuel. Research has therefore expanded with residual oil indicating that biomass from household and industrial waste has been technically feasible. The outcome of this investigation coincides with the enzyme production study of biodiesel utilising residual oil and ethanol, according to this principle. In esterification of commercial oleic acid, the behaviour of commercial immobilised lipase from CAL-B was examined and the variables affecting the process were investigated. Based on the results presented and discussed in this paper, the use of immobilized Candida antarctica lipase type B (CAL-B) for biodiesel production is more viable when using acidic substrates, since the best results were achieved with such raw materials and with a reaction rate comparable to esterification with an acid catalyst. The results of this work showed that the enzymatic esterification of commercial oleic acid with ethanol provided a conversion of 87.3% within 60 minutes of reaction, at a temperature of 30 °C, in a stoichiometric proportion and without adsorption of water. Both biocatalysts showed good stability, which produced over 80% conversion and 60 minutes of reaction and could be repeated without substantial loss of activity for at least 10 consecutive occasions