Oil palm empty fruit bunch derived microcrystalline cellulose supported magnetic acid catalyst for esterification reaction: An optimization study

The present work demonstrates a one-step preparation of Microcrystalline cellulose (MCC) based magnetic acid catalysts, using an in-situ impregnation process for the esterification of oleic acid. Commercial MCC and oil palm empty fruit bunch (EFB) derived MCC was used to synthesize the magnetic acid catalysts. The variation of synthesis conditions such as MCC loading, catalyst synthesis time, calcination temperature and time contributed to the development of commercial MCC supported magnetic acid catalyst (C-MCC/gamma-Fe2O3), and EFB MCC supported magnetic acid catalyst (EFB-MCC/gamma-Fe2O3). The EFB-MCC/gamma-Fe2O3 had a high acidity of 2.4 mmol/g under the optimized conditions: 5 g EFB-MCC loadings, 3 h catalyst synthesis time and calcination at 500 degrees C for 3 h. The catalyst showed good ferromagnetic properties contributed by maghemite, gamma-Fe2O3, in the catalyst. The catalyst also exhibited a mesoporous structure with a high specific surface area of 290.55 m(2)/g, pore volume of 0.249 cm(3)/g, and pore size of 3.5 nm. This could signify the catalytic efficiency of EFB-MCC/gamma-Fe2O3 catalyst via esterification of oleic acid. The influence of the esterification reaction parameters on the oleic acid conversion was investigated using the Box-Behnken optimization design. The highest esterification rate of 92.1% was obtained at the optimum reaction conditions of 9 wt% catalyst loadings, 12:1 methanol-oleic acid molar ratio and reaction time of 120 min at the fixed reaction temperature 60 degrees C. The EFB derived MCC magnetic acid catalyst displayed a good catalytic performance and rapid separation with reusability up to 5 times.