Efek Oksida Logam terhadap Sifat Fisis Minyak Sawit/Solar

Abstract

Indonesia's petroleum reserves are decreasing daily, due to the non-renewable nature of fossil fuels. Alternative energy sources are needed as a substitute for fuel by utilizing palm oil and diesel oil commonly called biodiesel. This synthesis was carried out by calcining natural sand at 750˚C and 1000˚C and reacting it with fatty acid methyl ester dimers in an autoclave. This study aims to process the dimerization of palm oil and diesel oil into fatty acid methyl esters with metal oxide catalysts from natural sand into liquid fuels. Metal oxide content in natural sand can increase catalytic activity because it has acid-base active sites. SEM-EDX results of natural sand catalysts contain the most dominant metal oxide is Al₂O₃ at 24.34% and increasing the variation of furnace temperatures, namely 750˚C and 1000˚C, causes the surface area of natural sand to increase so that the dimerization reaction of fatty acid methyl esters runs better. The fatty acid methyl ester dimers obtained were then characterized by FT-IR spectroscopy. The FT-IR spectrum shows the presence of absorption at wave numbers 2924.09 cm-1 and 2852.72 cm-1 which are asymmetrical and symmetrical C-H stretching vibrations of CH₂ which are supported by the presence of C-H bending vibrations at wave numbers 1462.04 cm-1 and 1375.25 cm-1. MEAL dimer was tested for its cetane number obtained by the dimerization process without catalyst which is 66.6 and with natural sand catalyst at 750˚C and 1000˚C respectively is 55.8 and 54.1 which shows a decrease in cetane number after the dimerization process. Then MEAL dimer analyzed for density decreased from MEAL dimer without catalyst which is 831.4 kg/m³ and MEAL dimer with catalyst which is 830.2 kg/m³ and 828.3 kg/m³. All parameters of physical properties analyzed are still within the standard range of SNI 7182: 2015.