Influence of the porous structure of a promoted Zn/Cr catalyst on efficiency and selectivity of the synthesis of methanol and higher alcohols from CO and H/sub 2/

This paper studies the influence of the porous structure of a promoted Zn/Cr catalyst on selectivity, efficiency, and thermal stability for the synthesis of methanol and higher alcohols from CO and H/sub 2/, at a pressure of 24.5 MPa in the range 300-420 C. It is shown that a variation of volume and size of the macropores in the catalyst samples changes the selectivity of the entire process. The sample with the highest selectivity towards higher alcohols also shows increased thermal stability. An increase of the CO/sub 2/ concentration in the synthesis gas leads to a decreased selectivity towards higher alcohols; an increase of the CO partial pressure enhances the selectivity to higher alcohols, although accompanied by a reduction of the overall CO conversion to useful products and by increased formation of methane and CO/sub 2/.