Novel zeolite Na-X synthesized from fly ash as a heterogeneous catalyst in biodiesel production

Abstract

Several studies have been carried out on the production of biodiesel using different heterogeneous catalysts but this study has been able to demonstrate the prospect of utilizing South African class F fly ash as a raw material for zeolite synthesis subsequently applied as a solid base catalyst in the production of biodiesel. A novel faujasite zeolite material synthesized from South African class F fly ash and denoted as FA/Na-X was ion exchanged with potassium to obtain the South African class F fly ash based zeolite FA/K-X. This heterogeneous catalyst was used in the conversion of sunflower oil with methanol to yield fatty acid methyl esters. Different characterization techniques were employed to give more information about this zeolite material. The FA/Na-X and the ion exchanged FA/K-X were applied as catalysts in biodiesel synthesis via transesterification reactions. A high quality biodiesel with a yield of 83.53% was obtained at reaction conditions of methanol:oil ratio of 6:1, catalyst amount of 3% (w/w) of oil and reaction temperature of 65 ◦C after 8 h.