Biodiesel production with waste product cycling

Abstract

Bio-derived fuels such as biodiesel and bioethanol have gained considerable attention as liquid transport fuels. Economic viability for large-scale bio-based fuel production in South Africa remains a contentious issue. This study aims to describe an enzymatic biodiesel production process, with a greater goal to stimulate small-scale biodiesel production in and around the country.

The possibility of using an E. coli host strain to develop a bacterial-biodiesel generating system was considered utilising a synthetic lipase for the trans-esterification of sunflower oil. The conditions for expression were evaluated with induction trials at 30 and 37 °C respectively; the concentration of IPTG was adjusted in 0.25 mM increments from 0 to 1 mM. The ideal concentration of IPTG was 0.75 mM, and the ideal temperature was 37 °C. The lipase's hydrolytic capacity was further evaluated on para-Nitrophenol palmitate, and the catalytic amount necessary was determined to be below 0.00729 µg for the substrate concentrations employed.