Influence of the precursors in CuZnAl slurry catalyst preparation by the complete liquid phase for the ethanol synthesis from syngas

Abstract

It has been found that CuZnAl slurry catalyst performance is influenced seriously by its precursors in ethanol synthesis from syngas. Herein, a series of the slurry catalysts were prepared by complete liquid phase method adopting different sol-gel and solution as components of precursors. Their catalytic performances were investigated in a slurry bed reactor and physicochemical properties were characterized by XRD, H2-TPR, NH3-TPD, N2 adsorption and XPS techniques. The results show that the catalyst Al–Zn(g)-Cu(s) prepared by adopting Zn gel and Cu solution as components of precursors exhibits the highest ethanol synthesis capacity, with the proportion of ethanol in the total alcohol reaching up to 45.36%. And no visible deactivation was detected over 168 h reaction. Characterization indicates larger Cu0 particles and a suitable range of surface Cu0/(Cu0+Cu+) ratios are favorable to the production of ethanol, the Cu0/(Cu0+Cu+) ratios can be adjusted partly by Cu0 particle sizes.