(437g) Effects of Structural Promoters on Cobalt Copper Catalyst for the Conversion of Syngas to Ethanol

Catalytic conversion of syngas derived from natural gas is an efficient way to convert natural gas to high value products. Ethanol is one of the promising alternative fuels that can be synthesized from syngas. Among the studies on monometallic and bimetallic catalysts for CO hydrogenation, Cu-Co bimetallic catalysts have been studied for ethanol and higher alcohols synthesis. In these catalysts, cobalt and copper in close proximity are designed to dissociate CO at Co sites and activate associative CO at Cu site.  This forms the critical C-C bond, creating intermediates that can convert to ethanol and higher oxygenates. In addition, structural promoters can increase ethanol selectivity with improved stability,  higher dispersion, and enhanced interaction between metals and promoters.

Here we present an experimental study of the Co-Cu catalysts that are synthesized with different structural promoters (ZrO2, Al2O3, MoOx and ZnO) using co-precipitation method. We characterize the catalysts using BET, TPR-H₂, TPD-NH₃, XPS and XRD to compare the effect of the structural promoters on surface area, catalyst dispersion, surface acidity, and reduction behavior. We examine the selectivity of the catalyst in CO hydrogenation to quantify product selectivity and to study thermal stability at temperatures at 270⁰C, 2/1 H2/CO, 40 bar in a fixed bed reactor to simulate the syngas derived from natural gas.