Thesis (M.Sc.)--Chulalongkorn University, 2005

The main objective of this research was aimed to study the catalytic cracking of used lubricating oil with Fe/SiO[subscript 2]-Al[subscript 2]O[subscript 3], Fe/Al[subscript 2]O[subscript 3] and Ni/Al[subscript 2]O[subscript 3] catalysts. The catalytic reaction was carried out in 70 ml micro-reactor volume. The 0.5-5 wt.% of iron on SiO[subscript 2]-Al[subscript 2]O[subscript 3] 5 wt.% of iron on Al[subscript 2]O[subscript 3] and 5 wt. % of nickel on Al[subscript 2]O[subscript 3] catalysis were prepared. The cracking process was performed at reaction temperature range from 390 to 470 degrees Celsius, reaction time range from 3 to 90 minutes, initial hydrogen pressure of to 200 psi and mass of catalyst was varied between 0 to 6.0% by wt. Liquid products were analyzed by Simulated Distillation Gas Chromatography, (DGC). The experimental result was found that 5% Fe/SiO[subscript 2]-Ai[subscript 2]O[subscript 3] gave highest % naphtha. The optimum condition of 5% Fe-SiO[subscript 2]-Al[subscript 2]O[subscript 3] was 450 degrees Celsius of reaction temperature, 75 minutes of reaction time, 100 psi of initial hydrogen pressure and 4.0% by wt. of Fe/SiO[subscript 2]-Al[subscript 2]O[subscript 3]. The liquid product yield in case of using 5% Fe/SiO[subscripy 2]-Al[subscript 2]O[subscript 3] was 76.24%, the liquid composition were consist of 45.35% of naphtha, 15.71% of kerosene, 22.83% of light gas oil, 3.70% of heavy gas oil and 12.41% of long residue. The liquid product yield in case of using 5% Fe/Al[subscript 2]O[subscript 3] was 80.38%, the liquid composition were consist of 35.14% of naphtha 14.47% of kerosene, 24.16% of light gas oil, 5.53% of heavy gas oil and 20.70% of long residue. The liquid product yield in case of using 5% Ni/Al[subscript 2]O[subscript 3] was 77.20%, the liquid composition were consist of 38.24% of naphtha, 15.67% of kerosene, 25.44% of light gas oil, 3.38% of heavy gas oil and 16.94% of long residue.