Light biofuel production from waste cooking oil via pyrolytic catalysis cracking over modified Thai dolomite catalysts

Renewable biofuels have gained increasing attention as a potential alternative fuel to decrease CO2 emission from combustion of fossil fuels. The aims of the work were to modify Thai dolomite by adding magnesium carbonate (MgCO3) at various contents (0-30 wt%), and used as catalyst in pyrolytic catalysis cracking (PCC) process to produce light biofuels including gasoline and kerosene. All catalysts were calcined at 600 degrees C for 4 h prior to the characterization and experiments. The physicochemical properties were done by various techniques such as X-ray diffractometer (XRD), N-2 adsorption-desorption, thermogravimetric analyzer and differential thermal analyzer (TGA-DTA), Field-emission scanning electron microscope (FE-SEM), and energy dispersive X-ray spectroscopy (EDX). The experiments of PCC process were carried out at different reaction temperatures of 450-550 degrees C. The results from XRD and SEM-EDX confirmed that the Mg was successfully added in Thai dolomite. The Mg content in the catalysts increased with increasing MgCO3 loadings. The calcination temperature of 600 degrees C cannot completely convert CaCO3 to CaO form. The pyrolytic oil and distilled oil yields and quality were affected by both Mg content and reaction temperature. In addition, pyrolytic oil was completely distillated according to ASTM D86 to separate into gasoline, kerosene, and diesel. The light biofuel production was enhanced with increasing Mg content in the reaction temperatures of 500 and 550 degrees C. The appropriate condition was suggested at reaction temperature of 500 degrees C with 20 wt% Mg/dolomite catalyst as it showed the highest production yield of about 84 vol% and light biofuel yield of about 65 vol%.