Title: Direct Conversion of Syngas into Methyl Acetate, Ethanol, and Ethylene by Relay Catalysis via the Intermediate Dimethyl Ether

Authors: Wei Zhou, Dr. Jincan Kang, Dr. Kang Cheng,  Shun He,  Jiaqing Shi,  Cheng Zhou, Prof. Dr. Qinghong Zhang,  Junchao Chen,  Prof. Dr. Luming Peng,  Prof. Dr. Mingshu Chen, Prof. Dr. Ye Wang

Abstract:

Selective conversion of syngas (CO/H₂) into C₂₊ oxygenates is a highly attractive but challenging target. Herein, we report the direct conversion of syngas into methyl acetate (MA) by relay catalysis. MA can be formed at a lower temperature (ca. 473 K) using Cu‐Zn‐Al oxide/H‐ZSM‐5 and zeolite mordenite (H‐MOR) catalysts separated by quartz wool (denoted as Cu‐Zn‐Al/H‐ZSM‐5|H‐MOR) and also at higher temperatures (603–643 K) without significant deactivation using spinel‐structured ZnAl₂O₄|H‐MOR. The selectivity of MA and acetic acid (AA) reaches 87 % at a CO conversion of 11 % at 643 K. Dimethyl ether (DME) is the key intermediate and the carbonylation of DME results in MA with high selectivity. We found that the relay catalysis using ZnAl₂O₄|H‐MOR|ZnAl₂O₄ gives ethanol as the major product, while ethylene is formed with a layer‐by‐layer ZnAl₂O₄|H‐MOR|ZnAl₂O₄|H‐MOR combination. Close proximity between ZnAl₂O₄ and H‐MOR increases ethylene selectivity to 65 %.

Full-Link：https://onlinelibrary.wiley.com/doi/10.1002/anie.201807113