PENGARUH KOMBINASI TULANG HEWAN DAN DAUN PEPAYA SEBAGAI KATALIS HETEROGEN TERHADAP KUALITAS BIODIESEL MINYAK KEDELAI

Abstract

The use of fossil fuels so far can cause a greenhouse effect and disrupt human health. Biodiesel acts as a more environmentally friendly alternative that can be produced using a transesterification reaction. Animal bones and papaya leaves contain high CaO so they have the potential to be heterogeneous catalysts in the biodiesel transesterification reaction instead of using a homogeneous catalyst which is corrosive. This study aims to determine the effect of using a catalyst from a mixture of animal bones and papaya leaves on the yield, density, and kinematic viscosity of biodiesel products and whether they meet SNI 7182: 2015 biodiesel standards. Animal bones and papaya leaves are cleaned and then heated for three hours using an oven, then heated in a furnace up to 800˚C for three hours to obtain CaO compounds. The material used for the production of biodiesel is pure soybean oil which is processed first using an esterification reaction. Soybean oil is heated at 60˚C with methanol with a Methanol to Oil Ratio (MTOR) of 3:1 in molar units and a sulfuric acid catalyst of three percent by mass of soybean oil for 90 minutes. The result of esterification is used as raw material for the transesterification process by reacting with methanol with MTOR 12:1 and CaO catalyst from animal bones and papaya leaves as much as 2 wt%, 4 wt%, and 6 wt% of soybean oil mass. The reaction was carried out using a closed Erlenmeyer with a controlled temperature of 65C˚ while stirring for two hours on a Hotplate Magnetic Stirrer. The results obtained showed that the yield increased from the sample with 2 wt% catalyst of 65.72% to 4 wt% catalyst of 70.36%, but the yield decreased when using 6 wt% catalyst to 68.88% due to saturation in the reaction. Based on the data that has been obtained, the best yield is obtained using 4 wt% catalyst of animal bones and papaya leaves with the density and kinematic viscosity values of biodiesel that meet SNI 7182:2015.