关键词: 磷化钨   ,   , 制备过程  ,   ,  热重分析  ,   ,  载体  ,   ,  助剂

Abstract: Diammonium hydrogen phosphate and ammonium metatungstate were used to prepare WP precursor. The impregnation and mixing methods were used to prepare the WP/γ-Al₂O₃ precursor with loading of 30%(counting by WO₃) , respectively. WP/γ-Al₂O₃ precursors by adding some content of promoter Ni,Co,V with loading of 30%(counting by WO₃) were also prepared with impregnation method, respectively. All catalysts were measured with thermogravimetric（TG）analysis in H₂ flow. The synthetic process of WP catalyst was studied. The effect of synthetic method and promoter on phosphiding extent of WP/γ-Al₂O₃ precursor was investigated. The results show that WP precursor can be reduced to WP completely in H₂ flow. W species on the surface of WP/γ-Al₂O₃ precursors prepared by impregnation or mixing methods can not be reduced to WP completely in H₂ flow . A substance with a similar structure of -Al-O-W-P is probably formed on the support surface. Compared with WP/γ-Al₂O₃ precursor by mixing method, W species is more difficult to be reduced to WP on the surface of WP/γ-Al₂O₃ precursor by impregnation method. It suggests that inginating reduced temperature of WP/γ-Al₂O₃ precursor is obviously decreased by adding promoter nickel(Ni). Cobalt(Co) increases the phosphiding extent of WP/γ-Al₂O₃ precursor. Adding vanadium(V) species on the surface of WP/γ-Al₂O₃ precursor is more different to be reduced to WP.

Key words: