Potassium acetate supported on activated carbon for transesterification of new non-edible oil, bitter almond oil

Abstract

Fatty acid methyl ester (biodiesel) was developed from new non-edible feedstock oil, bitter almond oil (BAO) through transestefication with methanol using potassium acetate supported on activated carbon (PA/AC) as a solid base catalyst. Activated carbon was prepared from waste of polyethyleneterphathalte, then the activated carbon was loaded with potassium acetate to prepare the heterogeneous solid base catalyst. Variables affecting yield of biodiesel such as, amount of potassium acetate impregnated in the activated carbon, amount of the catalyst, methanol to oil molar ratio, reaction temperature and reaction time, were investigated to optimize the reaction conditions. The biodiesel with the best yield (93.21 with an ester content of 97.01% w/w) and properties was obtained by using the catalyst loaded with 33.60wt.% of potassium acetate, 2.50% w/w of the solid catalyst, 9:1 methanol to oil molar ratio, 65°C reaction temperature and 150minutes of reaction. Properties of the prepared biodiesel exhibited that PA/AC is an effective solid base catalyst for the conversion of BAO into more valuable fuel. Moreover, properties of biodiesel were within the recommended biodiesel standards as prescribed by ASTM D 6751. The Fourier Transform Infra-red spectroscopy was used to ensure the conversion of BAO into biodiesel. Transesterification of BAO using the prepared solid base catalyst was found to fellow first order kinetics and the activation energy was calculated to be 56.74kJ/mol. The developed catalyst could be used up to four cycles with good conversion.