Preparation and properties of raney copper-zinc catalyst pellets for methanol synthesis

Abstract

Raney catalysts were produced by alkali leaching cylindrical pellets of a Cu-39 wt.pct.Al-17.8 wt.pct. Zn alloy to various depths using a range of leachant concentrations and temperatures. The resultant catalysts were then evaluated by measuring their activity to methanol synthesis from H 2-5 vol.pct. CO-4 vol.pct. CO 2 at 493 K and 4500 kPa. It was found that specific surface areas decreased with increasing leach depth, the decline being more pronounced at higher alkali concentrations and at higher leach temperatures. Specific activities, measured as pellet averages, increased with leach depth until they reached a maximum and then declined. The depths at which maximal activities were achieved increased with increasing alkali concentrations and decreasing temperatures. The overall result was to yield pellets for which catalytic activities were optimal for particular leach depths. Activities comparable to industrial oxide catalyst pellets were achieved under some leach conditions