Comparative Study of Heterogeneous Transesterification of Crude and Degummed Kapok Oil
Deborah Chidimma Nwakuba
Department of Chemical Engineering, Ahmadu Bello University, Zaria, Nigeria and Renewable Energy Division, National Research Institute for Chemical Technology, Zaria, Nigeria.
Ibrahim Ali Mohammed-Dabo
Department of Chemical Engineering, Ahmadu Bello University, Zaria, Nigeria.
Haruna Ibrahim *
Renewable Energy Division, National Research Institute for Chemical Technology, Zaria, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Crude and degummed kapok oils were transesterified with heterogeneous catalyst (calcium oxide) to determine its potency for biodiesel production in Nigeria. Calcium oxide catalyst was synthesized by supporting 15% hydrated lime on 85% by weight of alumina. The crude oil was degummed by heating it to 80oC with auto phosphoric acid for 30 minutes. It was then esterified to reduce free fatty acid content to 0.5 mgKOH/g. Some quantity of crude oil was also esterified as in degummed oil. The two oil samples were transesterified with 25% methanol (weight % of oil) with catalyst loading of 0.4%, 0.6%, 0.8%, 1.0% and 1.2% (weight of oil). The methyl esters yield of crude oil were; 5.0%, 32.92%, 58.97%, 48.39% and 53.79% and that of degummed were; 58.97%, 72.48%, 85.25%, 88.9% and 86.78%. The degummed oil had higher methyl esters content yet not up to minimum European Union Standard of 96.5%. It is therefore recommended to degum crude kapok oil before transesterification.
Keywords: Biodiesel, comparative study, crude, degummed, kapok oil.