Enhanced production of aromatics from syngas over CoMnAl oxides combined with -axis thickness tailored HZSM-5

• Published in: Materials chemistry frontiers 2024-04, Vol.8 (8), p.211-22
• Main Authors: Guo, Ruixin, Liu, Jia, Wang, Hao, Yu, Xing, Zhang, Jian, Yang, Chengguang, Li, Jiong, Sun, Yuhan, Gao, Peng
• Format: Article
• ISSN: 2052-1537
• DOI: 10.1039/d4qm00059e

The direct conversion of syngas to aromatics has a promising industrial future and can be achieved using bifunctional catalysts through olefin intermediates. However, the development of bifunctional catalysts with high aromatics yields remains a great challenge. In this work, we synthesized a series of HZSM-5 zeolites with different morphologies and pore structures and coupled them with CoMnAl oxides, which contain Co 2 C nanoprisms as the active phase and are highly efficient syngas to olefin catalysts, for aromatics synthesis directly from syngas. We demonstrate that a decreasing b -axis thickness and an appropriate density of Brønsted acid sites of HZSM-5 favors the syngas conversion to aromatics via bifunctional catalysis. The bifunctional catalysts with the smallest b -axis thickness of HZSM-5 zeolite of approximately 37 nm achieve a CO conversion of more than 70% under mild reaction conditions of 280 °C and 2.0 MPa, with high stability. The selectivity toward aromatics is higher than 65% with 3.5% selectivity toward by-product CH 4 and the aromatics yield is up to 27.1%. This study provides an exemplary new strategy for the efficient synthesis of aromatic hydrocarbons from syngas. A decreasing b -axis thickness and an appropriate density of Brønsted acid sites of HZSM-5 favors the syngas conversion to aromatics.