Biodiesel production from crude palm oil (CPO) through variation steps of esterification-transesterification and its evaluations

Indonesia is the world's largest supplier of palm oil. Crude palm oil (CPO) obtained from oil palms is expected to produce 60 million tons per year by 2045. This condition will not have a good impact if the production is not in line with its utilization. Therefore, research was conducted on the utilization of CPO, which can be used as a raw material for biodiesel to replace or at least reduce the use of conventional diesel. Therefore, in this study, CPO was converted into biodiesel with four different variation steps and evaluated for compliance with biodiesel standards. CPO contains triglycerides that can be separated into fatty acid methyl esters and glycerol through a transesterification process. Methanol solvent and KOH catalyst are used in this reaction, but before transesterification, the raw materials must be pretreated. After the entire production process was completed, fatty acid methyl esters were successfully converted into biodiesel. The biodiesel was then tested for conformity with the SNI 7182:2015 standard for the parameters of density, viscosity, percentage of ester content, and cetane number. The density results were 858.65; 856.30; 858.60; 863.20 Kg/m3. Viscosity is 1.3; 1.48; 1.25; 1.34 mm2/s. ester percentage by testing using GC-MS instrument and obtained consecutive results of 98.89; 97.99; 99.12; 99.03 percent. The dominant types of fatty acids found in the biodiesel samples were methyl oleate, methyl palmitate, and methyl stearate. Cetane numbers were analyzed with four variations. First is B100 (a mixture of biodiesel products). Second, B100+5% cetane number improver. Third, B100+10% cetane number improver. Last is B50 (50% mixture with DEXLITE). Successively obtained >75,00; >75,00; >75,00; 61,20. The results of the density, percentage of esters, and cetane number of the product showed conformity with biodiesel standards. As for the viscosity, it does not meet the standard because the value is too low.