Application of Response Surface Methodology for Optimization and Separation of Free Glycerol, Diglyceroids and Triglycerides from Biodiesel Using PES Ultrafiltration Membrane

Abstract

Abstract The available natural energy sources are inadequate to satisfy the demands of an increasing population and control environmental pollution. It is critical to prioritise alternative energy sources like biodiesel. Biodiesel is an eco-sustainable and renewable energy source. But impurities present in biodiesel causes problems in internal combustion engine and emission of hazards gases after burning, it must be separated in accordance with international standards. Conventional techniques are insufficient for separating impurities from biodiesel. Membrane separation technology has been found to be a cost-effective and environmentally friendly technique for biodiesel separation. In this study, 10 KDa polyethersulfone ultrafiltration membranes were used to separate impurities from biodiesel such as free glycerol, diglyceroids, and triglycerides. The response surface was used to analyse the influence of operating variables such as temperature, transmembrane pressure and water addition on impurity separation as well as optimization. The impurities were separated according to international standards and at optimal conditions, 96.45 % free glycerol, 54.37 % diglyceroids and 61.66 % triglycerides were removed at 60°C, 0.3 wt% water addition, and 2.6 bars transmembrane pressure. GRAPHICAL ABSTRACT