Abstract:
A series of CuZnAl catalysts were prepared by the complete liquid-phase method with different heat treatment times and characterized by XPS, XRD, H
2-TPR, NH
3-TPD-MS and N
2 adsorption-desorption; their catalytic performances in the synthesis of higher alcohols from syngas were investigated in a slurry bed reactor. The results indicate that an increase in the heat treatment time can enhance the interaction between the Cu and Al species and alter the amount of Cu
+ species over the CuZnAl catalysts, influencing the synergistic effect of Cu
+-Cu
0 sites. In addition, with the increase of heat treatment time, the surface acidity of CuZnAl catalyst decreases, accompanying with an increase in the pore volume and pore size; small amount of surface weak acid sites, large pore volume and large pore size are beneficial to the formation of higher alcohols. The CuZnAl catalyst obtained by heat-treating for 7 h exhibits excellent performance in the synthesis of higher alcohols, with a CO conversion of 38.1% and a higher alcohols mass fraction of 65.9% in the total alcohols.