Ti-modified alumina supports prepared by sol–gel method used for deep HDS catalysts
Ti-modified alumina supports prepared by sol–gel method used for deep HDS catalysts
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DOI：
10.1016/j.cattod.2007.10.029
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发表时间：
2008-02
期刊：
影响因子：
5.3
通讯作者：
Weiqiang Huang;A. Duan;Zhen Zhao;G. Wan;Guiyuan Jiang;T. Dou;K. Chung;Jian Liu
中科院分区：
文献类型：
--
作者：
Weiqiang Huang;A. Duan;Zhen Zhao;G. Wan;Guiyuan Jiang;T. Dou;K. Chung;Jian Liu
研究了不同负载量的NiMo/TiO2Al2O3型系列催化剂的典型物化性质及其加氢脱硫活性。在微反装置中，用两种商用柴油的混合物对催化剂进行了评价。采用氮气吸附、紫外-可见DRS、X射线衍射仪、傅立叶变换拉曼光谱、程序升温还原、吡啶红外光谱和漂移等技术对催化剂的表面和结构进行了表征。溶胶-凝胶法制备的样品具有较大的比表面积、孔体积和较大的平均孔径，适合于镍、钼活性成分的高分散性。UV-Vis DRS、X射线衍射谱和傅立叶变换拉曼光谱结果表明，锐钛矿型TiO2物种的存在促进了配位不饱和中心(CUS)或硫空位的形成，也促进了Mo活性相在催化剂表面的高度分散。NO在纯MoS_2和TiO_2负载量为15%和30%的催化剂上的漂移光谱表明，NiMo/TiO_2-Al_2O_3催化剂比纯MoS_2具有更多的CUS。HDS效率和上述表征结果证实，在Al_2O_3中引入TiO_2可以调节载体与活性金属之间的相互作用，增强钼的还原能力，从而使HDS反应具有较高的活性。
The typical physico-chemical properties and their hydrodesulfurization activities of NiMo/TiO2-Al2O3series catalysts with different TiO2loadings were studied. The catalysts were evaluated with a blend of two kinds of commercially available diesels in a micro-reactor unit. Many techniques including N2-adsorption, UV–vis DRS, XRD, FT-Raman, TPR, pyridine FT-IR and DRIFT were used to characterize the surface and structural properties of TiO2-Al2O3binary oxide supports and the NiMo/TiO2-Al2O3catalysts. The samples prepared by sol–gel method possessed large specific surface areas, pore volumes and large average pore sizes that were suitable for the high dispersion of nickel and molybdenum active components. UV–vis DRS, XRD and FT-Raman results indicated that the presence of anatase TiO2species facilitated the formation of coordinatively unsaturated sites (CUS) or sulfur vacancies, and also promoted high dispersion of Mo active phase on the catalyst surfaces. DRIFT spectra of NO adsorbed on the pure MoS2and the catalysts with TiO2loadings of 15 and 30% showed that NiMo/TiO2-Al2O3catalysts possessed more CUS than that of pure MoS2. HDS efficiencies and the above characterization results confirmed that the incorporation of TiO2into Al2O3could adjust the interaction between support and active metals, enhanced the reducibility of molybdenum and thus resulted in the high activity of HDS reaction.