Effect of yttrium on catalytic performance of Y-doped TiO_(2) catalysts for propane dehydrogenation  

作　　者：Liyu Hou Liming Xia Ruipeng Zhou Jianmei Li Renjie Li Zhen Zhao Guimei Yuan Aijun Duan 

机构地区：[1]State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing,102249,China [2]Institute of Catalysis for Energy and Environment,College of Chemistry and Chemical Engineering,Shenyang Normal University,Shenyang,110034,China

出　　处：《Journal of Rare Earths》2024年第5期962-971,I0005,共11页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(22172192,92145301);National Key Research and Development Program(2021YFB3500603)。

摘　　要：Defective bulk catalysts based on TiO_(2) have superior catalytic performance for propane dehydrogenation(PDH).The oxygen vacancy concentration and the number of active sites on the catalyst surface can be effectively tuned by doping metal in TiO_(2).Herein,yttrium(Y)-doped titanium dioxide(nY/TiO_(x))catalysts were in-situ synthesized via the coprecipitation method to study the effect of rare earth metal Y doping on the structure of TiO_(2) and the catalytic performance for PDH.Experimental results demonstrate that Ydoped TiO_(2) exhibits higher catalytic activity,propylene selectivity and stability than bare TiO_(2).Full characterizations with X-ray diffraction(XRD),high-resolution transmission electron microscope(HRTEM),X-ray photoelectron spectroscopy(XPS),infrared spectroscopy of pyridine adsorption(Py-IR),temperature-programmed desorption of ammonia(NH_(3)-TPD),H_(2) temperature-programmed reduction(H_2-TPR),and Raman techniques on these catalysts reveal that Y^(3+)can enter TiO_(2) lattice,and the lattice stability of the catalyst can be enhanced by replacing Ti^(4+)to form Y-O-Ti structure.Meanwhile,the introduction of an appropriate amount of Y can obviously promote the PDH reaction by adjusting the acidity of the catalyst,improving the release capacity of TiO_(2) lattice oxygen and increasing the formation of active centers.Nevertheless,excessive Y doping will lead to pore clogging,and the exposure of active sites will be reduced,resulting in the degradation of catalytic performance.

关 键 词：Propane dehydrogenation ANATASE Lattice defects Coordinatively unsaturated Ti cations Oxygen vacancy Rare earths 

分 类 号：O64[理学—物理化学]