Transesterification of palm oil using heterogeneous NaOH/A12O3 catalyst for biodiesel production

• Main Author: Abdullah, Nurul Fitriyah
• Format: Thesis
• Language: English; English
• Published: 2011
• Subjects: Palm oil; Transesterification; Biodiesel fuels
• Online Access: http://psasir.upm.edu.my/id/eprint/25741/1/FS%202011%20106R.pdf; http://psasir.upm.edu.my/id/eprint/25741/
• Institution: Universiti Putra Malaysia

Biodiesel fuel has become more attractive recently because of environmental concerns and the limited resources of fossil fuel. Biodiesel also recognized as “green fuel” with several advantages, ie; safe, non-toxic and biodegradable compared to petroleum diesel. In this work, biodiesel production by transesterification of palm oil with methanol has been studied in a heterogeneous system using sodium hydroxide loaded on alumina. A series of solid base catalyst consisting of NaOH supported on commercial alumina were prepared for the transesterification of palm oil with methanol in order to find a support which can work better compared to homogeneous catalyst. During catalyst preparation, different amount of sodium compounds were impregnated into alumina. A screening of the reaction conditions has been carried out by examining the effect of methanol/oil molar ratio, catalysts amount, reaction temperature and reaction time. The prepared catalysts were then characterized by using X-Ray Diffraction (XRD) Analysis, Fourier Transform Infrared (FT-IR) Spectrometer, Brunner-Emmett-Teller (BET) Surface Area Measurement, Scanning Electron Microscopy (SEM) and Temperature Programmed Desorption of Carbon Dioxide (CO2-TPD). Gas Chromatography (GC) and FT-IR was further used for characterization of biodiesel samples. The experimental results indicated that alumina supported with 50 wt% NaOH and calcined in air at 250°C for 3h (50NaC)gave the highest basicity and the best catalytic activities for transesterification reaction. The catalytic activities of the catalyst are explained by formation of aluminates that originated the stronger basic sites of the catalyst. The formation of aluminates is shown by characterization using XRD and FT-IR. The highest conversion 99% reached when the transesterification reaction was carried out at 15:1 methanol/oil molar ratio with 3 wt% catalyst, reaction temperature 60°C and reaction time 3h.