Deactivation of a Cu/ZnO/Al2O3 Based Methanol Catalyst by HCN

HCN seems to block required active sites for the methanol synthesis over Cu/ZnO/Al₂O₃ at lower temperatures. At higher temperatures HCN becomes a reversible poison, as activity is slowly regained when HCN free syngas again is dosed. HCN is dependent on operating conditions converted to different products.