加料方式对CuO/ZnO/Al2O3系催化剂前驱体性质的影响

The influence of precipitation method on the precursors of CuO/ZnO/Al2O3 catalysts were studied by XRD,TG-DTG and TPR techniques. The catalytic activity of the catalysts for methanol synthesis was tested using a differential fixed-bed reactor. It is found that the feeding method has strong influence on the Cu precursors in CuO/ZnO/Al2O3 catalyst. In case of base to salt, the initial precipitate was crystal Cu2(OH)3NO3; while in the case of co-current, the initial phase was mainly amorphous Cu2CO3(OH)2. The feed method has no effect on the initial phase composition and crystallinity of Zn-precursor and Zn5(CO3)2(OH)6 was the unique phase in the precursors. The phases of (Cu, Zn)2CO3(OH)2 and (Cu, Zn)5(CO3)2(OH)6 in the precursors of the catalyst were produced from the substitution of Cu2CO3(OH)2 (amorphous) and Zn5(CO3)2(OH)6. The activity of the catalyst was in the order of co-current>salt to base >base to salt.