Preparation, Characterization, Hydrodesulfurization and Hydrodenitrogenation Activities of Alumina-supported Tungsten Phosphide Catalysts  

作　　者：李翠清 孙桂大 李成岳 宋亚娟 

机构地区：[1]The Key Laboratory of Science and Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China [2]The Green Chemistry and Catalysis Materials Laboratory, Beijing Institute of Petrochemical Technology, Beijing 102617, China

出　　处：《Chinese Journal of Chemical Engineering》2006年第2期184-193,共10页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No.200273011), the National 973 Project (No.G2000048003)and the Beijing Natural Science Foundation (No.2052009).

摘　　要：Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%—37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperature-programmed reduction of supported tungsten phosphate (precursor of WP/Al2O3 catatlysts) in H2 at 650℃ for 4h. The catalysts were characterized by XRD, BET, TG/DTA , XPS and 31P MAS-NMR. The activities of these catalysts were tested in the hydrodenitrogenation (HDN) of pyridine and hydrodesulfurization (HDS) of thiophene at 340℃ and 3.0MPa. The results showed that owing to the stronger interaction of the support with the active species, the precursor of WP/Al2O3 catalyst was more difficultly phosphided and a greater amount of W spe- cies was in a high valence state W6+ on the surface of the catalyst prepared by the impregnation method than that by the mixing method. 31P MAS-NMR results indicated that 31P shift from 85% H3PO4 of 2.55×10-4 for WP and 2.57 ×10-4 for WP/γ-Al2O3 catalysts prepared by mixing method. Such WP/Al2O3 catalysts showed higher HDN activi- ties and lower HDS activities than those prepared by the impregnation method under the same loading of WP. WP/γ-Al2O3 catalysts with weak interaction between support and active species were favorable for HDN reaction while the WP/γ-Al2O3 catalysts with strong interaction were favorable for HDS reaction.Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%-37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperature-programmed reduction of supported tungsten phosphate （precursor of WP/Al2O3 catatlysts） in H2 at 650℃ for 4h. The catalysts were characterized by XRD, BET, TG/DTA, XPS and ^31p MAS-NMR. The activities of these catalysts were tested in the hydrodenitrogenation （HDN） of pyridine and hydrodesulfurization （HDS） of thiophene at 340℃ and 3.0MPa. The results showed that owing to the stronger interaction of the support with the active species, the precursor of WP/Al2O3 catalyst was more difficultly phosphided and a greater amount of W species was in a high valence state W^6＋ on the surface of the catalyst prepared by the impregnation method than that by the mixing method. 31p MAS-NMR results indicated that 31p shift from 85% H3PO4 of 2.55 × 10^-4 for WP and 2.57 × 10^-4 for WP/γ-Al2O3 catalysts prepared by mixing method. Such WP/Al2O3 catalysts showed higher HDN activities and lower HDS activities than those prepared by the impregnation method under the same loading of WP. WP/γ-Al2O3 catalysts with weak interaction between support and active species were favorable for HDN reaction while the WP/γ-Al2O3 catalysts with strong interaction were favorable for HDS reaction.

关 键 词：HYDRODESULFURIZATION HYDRODENITROGENATION tungsten phosphide PYRIDINE THIOPHENE 

分 类 号：O643.36[理学—物理化学]