Thesis (M.Sc.)--Chulalongkorn University, 2013

The waste tire is one of alternative energy sources due to its long hydrocarbon chains with high heating value. However, the oil derived from waste tire pyrolysis is not suitably used in any combustion engines since it contains a huge volume of sulfur compounds. Therefore, the aim of this research was to improve the waste tire pyrolysis oil via hydrodesulfurization catalyzed by using 3 types of catalysts supported on γ-alumina: molybdenum (Mo/γ-Al2O3), nickel-molybdenum (NiMo/γ-Al2O3) and cobalt-molybdenum (CoMo/γ-Al2O3). The catalyst prepared by successive incipient wetness impregnation method. The effects of catalyst loading (0-2 wt% based on the amount of waste tire pyrolysis oil), initial hydrogen pressure (10-50 bar), reaction temperature (150-350 °C), and reaction time (5-60 min) on the %sulfur removal were investigated. The maximum %sulfur removal at 87.8% was achieved when the reaction was carried out at 250 °C for 30 min by using 2 wt% of catalyst loading and 20 bar of initial hydrogen pressure. The amount of sulfurous compounds in the waste tire pyrolysis oil was determined by using gas chromatography equipped with a flame photometric detector (GC-FPD). The results indicated that hydrodesulfurization of waste tire pyrolysis oil was effective to reduce the sulfurous compounds; especially, thiophene and its derivatives.