Preparation And Catalytic Performance Evaluation Of The Alkylation Catalysts For FCC Gasoline Desulfurization

With the enforcement of increasingly stringent environmental laws, strict regulations of the sulfur levels in gasoline have been carried out around the world. In this study, three kinds of alkylation catalysts were prepared and investigated to removal thiophenic sulfur from FCC gasoline, and to provide fundamentally technical support for the development of thiophenic sulfur alkylation technology.The PW-SiO₂ catalysts were prepared respectively by impregnation and sol-gel method and then were applied to the desulfurization experiments. The influences of preparation methods, support type and activation temperature on the catalytic performance of the PW-SiO₂ catalysts was studied for the alkylation reaction. The results indicated that the catalytic performance of the catalyst prepared by impregnation were better than that of the catalyst prepared by sol-gel method. The conversion of thiophene alkylation of 78.8% was obtained under reaction temperature 80℃, reaction time 4h, reaction pressure 0.3MPa, the mass ratio of the catalyst to feed 4∶100. The catalysts could be used repeatedly. The BET characterization indicated that the specific surface area of the catalysts is not large enough.The AlCl₃-NKC9 catalysts were prepared respectively by incipient impregnation and excessive impregnation method, and then were applied to the desulfurization experiments. The influences of preparation methods, reaction condition on the catalytic performance AlCl₃-NKC9 catalysts was studied for the alkylation reaction. The results indicated that the catalytic performance of the catalyst prepared by incipient impregnation were better than that of the catalysts prepared by excessive impregnation. The conversion of thiophene alkylation reached to 93.5% under reaction temperature 100℃, reaction time 4h, rection pressure 0.3MPa, the mass ratio of the catalyst to feed 4∶100. After used 6 times, the conversion of thiophene alkylation still reached to 80%. The AAS (Atomic Adsorption Spectrometric) characterization indicated that the active element loaded on the catalyst was lost graduallyThe PW-NKC9 catalysts were prepared. The influences of preparation methods, loading amount, reaction temperature on the catalysis performance of the catalysts was studied for thealkylation reaction of FCC gasoline. For the catalyst with loading amount 0.048 g/g, the conversion of thiophene alkylation of 90.1% was obtained under reaction temperature 100℃, reaction time 4h, rection pressure 0.3MPa, the mass ratio of the catalyst to feed 4∶100. The stability of the catalyst was fair.