Nanocomposites comprising cellulose and nanomagnetite as heterogeneous catalysts for the synthesis of biodiesel from oleic acid

A nanocomposite comprising cellulose and nanomagnetite based on rice husk cellulose was used as the catalyst for the formation of methyl esters from oleic acid as an alternative method for biodiesel production. The resulting nanocomposite properties supported by FTIR, XRD, SEM and TEM characterization revealed that nanomagnetite Fe₃O₄ had impregnated the acetylated nanocellulose. The nanomagnetite Fe₃O₄ obtained had an average size of 30 nm. The best conversion of oleic acid to methyl esters for the catalytic application of the nanocomposite was 89.21%, which was achieved at a reaction temperature of 60°C, reaction time of 5 hours, catalyst concentration of 1.5 wt.%, and ratio of oleic acid to methanol of 3:1. Kinetic analysis at different temperatures (40, 50, 60 and 70°C) was performed, and a low activation energy of 16.56 kJ/mole was obtained. These results indicate that the biopolymer-based nanocomposite utilizing nanocellulose from rice husks composited with inorganic Fe₃O₄ nanoparticles has good potential for use as a green biocatalyst, and the proposed reaction can be used as an innovative new method to produce biodiesel in the future.