Transesterification of soybean oil to biodiesel using CaO as a solid base catalyst

• Published in: Fuel (Guildford) Vol. 87; no. 2; pp. 216 - 221
• Main Authors: Liu, Xuejun, He, Huayang, Wang, Yujun, Zhu, Shenlin, Piao, Xianglan
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2008; Elsevier
• Subjects: Applied sciences; Biodiesel; Biomass; Calcium oxide; Energy; Exact sciences and technology; Natural energy; Solid base catalyst; Soybean oil; Transesterification; Solid base catalyst; Calcium oxide; Transesterification; Soybean oil; Biodiesel; Experimental result; Diesel fuel; Water content; Reaction mechanism; Biofuel; Catalyst; Methanol
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2007.04.013

In this study, transesterification of soybean oil to biodiesel using CaO as a solid base catalyst was studied. The reaction mechanism was proposed and the separate effects of the molar ratio of methanol to oil, reaction temperature, mass ratio of catalyst to oil and water content were investigated. The experimental results showed that a 12:1 molar ratio of methanol to oil, addition of 8% CaO catalyst, 65 °C reaction temperature and 2.03% water content in methanol gave the best results, and the biodiesel yield exceeded 95% at 3 h. The catalyst lifetime was longer than that of calcined K 2CO 3/γ-Al 2O 3 and KF/γ-Al 2O 3 catalysts. CaO maintained sustained activity even after being repeatedly used for 20 cycles and the biodiesel yield at 1.5 h was not affected much in the repeated experiments.