Biodiesel Production Process from Crude Palm Oil using Calcium Oxide Derived from Cockle Shells as Economical and Green Catalyst

Abstract

In this study, crude palm oil was used as a starting material for biodiesel production with methanol. Since crude palm oil has a high free fatty acid (FAA) content and gum, consequently, esterification reaction was applied to reduce FAA from 7.25 wt.% to 1.50 wt.% by using H₂SO₄ as a catalyst. Next step, transesterification reaction was used to transform the crude palm oil which reduced free fatty acid to be biodiesel product catalyzed by cockle shells-derived CaO catalyst. Under the optimal reaction conditions at CaO catalyst loading at 6 wt.%, methanol/oil molar ratio of 12:1 and reaction temperature of 65 °C; %FAME of 98.7% (±1.5) and amount of biodiesel yield as 87% (±2), were achieved within reaction time of 3 h and this catalyst could be reused for at least 4 times. In the last phase of the study, the physicochemical properties of the obtained biodiesel after purification and treatment processes were evaluated and it was found that the biodiesel was of a high quality product according to American Society for Testing and Material (ASTM) methods and European Standard methods (EN14214) for bio-auto fuels.