Abstract:
The present thesis investigated preparation of heterogeneous base catalysts from shell for transesterification of palm oil with methanol. The catalysts were prepared by dissolution-precipitation method. Typically, shell was previously calcined 400-800 ˚C after which it was mixed with Zn(NO3)2 solution and Al2O3 under acidic conditions. The catalysts were attained after the calcination at 300-900 ˚C for 2 h. Effects of the catalysts preparation, including method composition, calcination temperature for shell, calcination temperature for catalysts, pH of synthesis of slurry mixture and step for adding catalyst ingredients, were investigated. The physicochemical properties of the catalysts were studied by using X-ray fluorescence spectroscopy (XRF), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric/differential thermal analysis (TG/DTA), scanning electron microscopy (SEM), temperature-programmed desorption of CO2 (CO2-TPD) and CO2- pulse chemisorption analysis. The suitable optimum conditions for preparing the catalysts are the amount of zinc oxide of 30 wt.% relative to alumina weight, adjust the pH of Zn(NO3)2 solution of 1, calcination temperature for shell of 600˚C and calcination temperature for catalyst of 500 ˚C. The catalyst attained gave the highest methyl ester yield of 99 wt.% at the methanol/oil molar ratio of 30, amount of catalyst of 10 wt.%, reaction temperature of 60˚C, reaction time of 3 h. The catalyst can be reused at least 5 times, giving the methyl ester yield of 96 wt.%