Analysis of Collision Theory in the Production of Candlenut Oil Biodiesel Using a Zeolite-KOH Catalyst

Moondra Zubir ((Scopus ID: 57188681604 SINTA ID: 5996528) Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Negeri Medan, Medan)
Joice Evelyn Simamora
Gian Devina Gracia Nehe
Mardiyah Tsani

Indonesian Journal of Chemical Science and Technology
Vol. 9 No. 2 (2026): JULY 2026

The methanol-to-oil ratio is one of the most important factors affecting biodiesel production through transesterification. This study investigated the effect of different methanol-to-oil ratios (1:2, 1:4, 1:6, 1:8, and 1:10) on biodiesel production from candlenut oil (Aleurites moluccanus L.) using KOH-activated zeolite catalyst from a collision theory perspective. Biodiesel was produced through transesterification at 60–65 °C with a stirring speed of 300 rpm for 1 h. The resulting biodiesel was characterized based on yield, volume, and density. The results showed that increasing the methanol-to-oil ratio up to 1:6 increased biodiesel yield and improved product quality. The highest yield of 95.47% was obtained at a ratio of 1:6 with a density of 0.850 g/mL. Further increases in methanol concentration reduced biodiesel yield. Based on collision theory, the 1:6 ratio provided the optimum condition for effective molecular collisions during transesterification.