Purification of biodiesel products from transesterification process using Ion-Exchange Resin

Abstract

Biodiesel based on crude palm oil (CPO) is gaining attention as a replacement for current fossil fuels due to high production of CPO locally in Malaysia other than government influence on findings solution for global problems regarding to the usage of petrodiesel. As a result, CPO is claimed to be a highly potential feedstock for food origin biodiesel. An acid catalyzed esterification process using sulphuric acid (H2SO4) was carried out to evaluate the low content of free fatty acids (FFA) in the treated CPO with the effects of other parameters such as methanol to oil molar ratio (6:1), reaction temperature (40–80 °C), reaction time (30–120 minutes) and stirring speed (600 rpm) using PORIM method. The results showed that the FFA of CPO was reduced from 4.24 % to less than 1.0 % FFA using 1.0 % wt/wt. of H2SO4. Response surface methodology (RSM) in conjunction with the central composite design (CCD) was employed to statistically evaluate and optimize the biodiesel production process. It was found that the production of biodiesel have achieved an optimum level of 89.23 % biodiesel yield at the following reaction conditions; (i) methanol to oil molar ratio of 13:1, (ii) reaction time of 120 minutes, (iii) reaction temperature of 62.64 °C, and (iv) stirring speed of 771.86 rpm. Purification of biodiesel products show that the fatty acid methyl esters (FAME) concentration increased from 89.23 % (without purification) to 91.31 % (150 minutes purification time). Fourier Transform Infrared (FTIR) Spectrometry analysis be evidence for the existence of ester group in produced biodiesel at the wavenumbers between 1780 to 1640 cm-1. Therefore, the verification of the efficiencies of ion-exchange resin can be concluded as a good purification method.