In this study, crude Calophyllum inophyllum oil was used as the feedstock for biodiesel production. This feedstock contain high acid value of 56.3 mg KOH/g (28wt%) which is not favorable for direct conversion to biodiesel by transesterification. Therefore, this paper emphasizes the study on the pre-treatment process of degumming and acid catalyst esterification in order to reduce the high free fatty acid for successful transesterification. Single parameter study was conducted to identify the best acid with best concentration to efficiently esterify the degummed Calophyllum inophyllum oil with highest FFA conversion. Among phosphoric acid, hydrochloric acid, and sulphuric acid, 3.0M concentration of sulphuric acid was found to be the best condition for the esterification reaction providing 87.46% FFA conversion.
Keywords biodiesel, Calophyllum inophyllum, esterification, degumming