Space-Confined-Self-Regulation Mechanism from Capsule Catalyst to Realize an Ethanol Direct Synthesis Strategy

Capsule catalyst, being composed of catalytic zeolite membrane and catalyst core, can accomplish multiple catalysis reactions or several organic synthesis reactions in a single step, enhancing energy efficiency, erasing unnecessary separation engineering and creating many unexpected synergistic effects via tandem catalysis. This report discloses an ethanol synthesis strategy from syngas (CO+H2) and syngas-derived dimethyl ether (DME) by a tailor-made catalyst with a macroscopic capsule structure. The macroscopically designed capsule catalyst consisted of a millimeter-sized Cu/ZnO core and a micrometer-sized H-Mordenite zeolite shell. The catalyst preparation process further successfully fabricated zeolite shell, migrated few Cu from core, as the promoter of shell, to significantly improve catalyst performance. As the methanol byproduct can be easily recycled to DME as reactant via simple dehydration reaction, ethanol selectivity can reach 100% theoretically. It is demonstrated that a space-confined-self-r...