2902
Energy & Fuels 2008, 22, 2902–2908
Promoting Effect of SO42- on Desulfurization Activity on Ni/ Supports for Fluidized Catalytic Cracking (FCC) Gasoline Wenshou Wang, Hongchen Guo, Haiou Liu, and Xiangsheng Wang* Department of Catalytic Chemistry and Engineering and State Key Laboratory of Fine Chemicals, Dalian UniVersity of Technology, Dalian 116012, China ReceiVed March 24, 2008. ReVised Manuscript ReceiVed May 23, 2008
World-wide changes in clean fuel regulations have accelerated the research works for reducing sulfur in fluidized catalytic cracking (FCC) gasoline. In this work, NiSO4 and Ni(AC)2 were supported on nano-HZSM5, Al2O3, and SiO2 supports by impregnation to prepare catalysts modified by NiSO4 and NiO. The catalysts were characterized using X-ray powder diffraction (XRD), nitrogen adsorption (BET), NH3 temperatureprogrammed desorption (TPD), Fourier transform infrared (FTIR) analysis with adsorbed pyridine, H2 temperature-programmed reduction (TPR), and differential thermogravimetric (DTG) analysis. NH3-TPD shows that the acid sites and acid strength is increased after NiSO4 modification and decreased after Ni(AC)2 modification. FTIR results indicate that most of the increased acidity is Lewis acid. Infrared spectra before and after pyridine adsorption demonstrate that there is a strong interaction between SdO in SO42- and alumina oxides. The interaction makes NiSO4 on the surface of alumina oxides harder to decompose than pure NiSO4 and SO3 in sulfate anion much more difficult to be reduced. This interaction results in more stable desulfurization activity of NiSO4/Al2O3 than that of NiO/Al2O3. However, there is no interaction between NiSO4 and SiO2.
1. Introduction Environmental regulations have resulted in needs for clean transport fuels. Europe’s current gasoline sulfur specifications have been lowed to 50 µg/g after 2005. The limit of sulfur in gasoline in the U.S.A. is below 30 µg/g after 2005. Moreover, “sulfur-free” (
