Hydrotreating of Sunan Candlenut Oil using NiMo/-Al₂O₃Catalyst for Renewable Diesel Production

Catalytic hydrotreating process based on NiMo/-Al2O3 has been conducted in this study using Sunan candlenut oil as the feedstock, in order to obtain renewable diesel products as well as conventional diesel. Hydrotreating process was performed with the variation of several operating conditions including pressure, temperature and weight ratio of catalyst to vegetable oils. Products obtained were then analyzed using Gas Chromatography (GC) and tested to obtain physical and chemical properties. Based on GC results, it was showed that the increase in operating pressure and temperature also increase the yield of hydrocarbon products in the range of diesel, with the highest yield of 30.95% at a pressure of 60 bar and temperature of 400°C. The conversion and selectivity were 33.48% and 95.72%, respectively, where the reaction route tends to the decarbonylation mechanism. However, changes in the weight ratio of catalyst to the vegetable oil did not affect the overall product yield. Analysis of physical and chemical properties of the product prior to distillation showed a decrease in the value of density, viscosity, iodine numbers and acid numbers are quite significant and closer specification commercial diesel oil.