Synthesis and characterization of silica-supported transition-metal phosphides as HDN catalysts

摘要

Supported transition-metal phosphides (Co_2P/SiO_2,MoP/SIo_2,WP/SIo_2 CoMoP/SiO_2 and NiMoP/SiO_2) were prepared by means of pore-volume impregnation of a silica support The metal oxide/phosphate precursore were reduced either in pure H_2 or in flow of 4.8 H_2 in Ar The materials obtained were characterized by CO chemisorption powder X-ray diffractometry and ~31P MAS NMR spectroscopy The catalysts were tested in the hyrodenitrogenation of o-methylaniline at 643 K and 3MPa in the presence and absence of H_2S All the materials were active in this reaction MoP/SiO_2 displaying the highest catalytic activity In the presence of H_2S,all the catalysts lost some activity.