Effect of Catalyst Modification Method of Chicken Manure Catalyst on Optimal Biodiesel Production From Waste Cooking Oil

Abstract

In this study, chicken manure modified with nickel sulphate using three modification methods; wet impregnation, sol-gel and hydrothermal methods for the production of biodiesel from waste cooking oil. The influence of the modification method on the optimum yield of biodiesel was studied. Brunauer-Emmett and Teller analysis, fourier transform infrared spectroscopy, scanning electron microscope, X-ray diffraction, and X-ray fluorescence were used in characterizing the modified catalysts. Optimization of biodiesel production was carried out using response surface methodology to determine optimum yield. The efficiencies of the catalysts were tested via reusability analysis. The catalysts characterization revealed high surface area, with catalyst modified using sol-gel method having the highest surface area and pore volume of 355.36 m²/g and 0.23 cc/g. Acidic and basic oxides such as CaO, SiO2, NiO, SO3, Al2O3 and Fe₂O3 in significant quantities were present in the catalysts produced. Also, the sol gel modified catalyst performed best with optimum yield of 96.82 % with methanol/oil ratio of 12.98:1, catalyst loading of 3.66 wt.%, temperature of 59℃, and reaction time of 86.45 minutes. High biodiesel yields greater than 70 % after four cycles were observed using the catalysts. The produced biodiesel were all within the acceptable limits by ASTM D6751 and EN 14214 standards.