Biocatalytic Production of Biodiesel from Spent Coffee Grounds

Abstract

Abstract-Production of biodiesel was carried out by transesterification of spent coffee oil with methanol, using lipases as catalysts. The conversion of spent coffee oil to fatty acid methyl esters (FAME) were investigated by screening different lipases, Candida rugose, Porcine pancreas, Pseudomonas fluorescens and Candida antarctica lipase-B. Optimal reaction conditions were obtained by varying the oil to methanol molar ratio, temperature and reaction time. Maximum conversion (96.33 %) of spent coffee oil to FAME was found when using Candida antarctica lipase-B as catalyst, at 1:4 oil to methanol molar ratio and a temperature of 40 ºC for 12 h. Total coffee waste produced at the North-West University (Potchefstroom Campus) could result in 162 kg of biodiesel that could be added to annual fuel supply for the campus.