Promoting Effect of SO42− on Desulfurization Activity on Ni/Supports for Fluidized Catalytic Cracking (FCC) Gasoline

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• 作者：Wenshou Wang ; Hongchen Guo ; Haiou Liu ; Xiangsheng Wang
• 刊名：Energy & Fuels
• 出版年：2008
• 出版时间：September 17, 2008
• 年：2008
• 卷：22
• 期：5
• 页码：2902-2908
• 全文大小：266K
• 年卷期：v.22,no.5(September 17, 2008)
• ISSN：1520-5029

文摘

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-HZSM-5, 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 temperature-programmed 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 SO 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.