Enhancing selectivity of aromatics in direct conversion of syngas over K/FeMn and HZSM-5 bifunctional catalysts

• Published in: Molecular catalysis Vol. 533; p. 112790
• Main Authors: Kang, Seok Chang, Park, Gyungah, Kwak, Geunjae, Zhang, Chundong, Jun, Ki-Won, Kim, Yong Tae, Choi, Minkee
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2022
• Subjects: Higher olefin; Hydrocarbon distribution; One-stage reaction; Syngas to aromatics; Syngas to aromatics; Hydrocarbon distribution; One-stage reaction; Higher olefin
• ISSN: 2468-8231; 2468-8231
• DOI: 10.1016/j.mcat.2022.112790

•The effect of FTS-derived HC distribution on the yield of aromatics was investigated in a single step STA reaction with K/FeMn + H-ZSM5 catalysts.•The C6-C10 distribution was increased by the addition of Mn due to the improved dispersion of Fe7C3 and alkyl insertion of MnO.•At 340 °C under 20 bar, 97.2% CO conversion and 39.8% aromatics selectivity were achieved by using catalyst of K/FeMn with Mn/(Fe+Mn) 60 wt% and H-ZSM5 with an optimization of the C6-C10 olefin yield. Mixed Fischer-Tropsch synthesis (FTS) catalysts and HZSM-5 (HZ5) have received attention as bifunctional catalysts that directly convert syngas into value-added aromatic monomers. However, both low selectivity of aromatics and severe deactivation remain challenges. Here we report a simple method for obtaining selective aromatics from syngas by tuning the distribution of hydrocarbon (HC) intermediates on K/FeMn. We prepared K/FeMn catalysts with a varying Mn/(Fe+Mn) wt% to demonstrate the effect of the HC distribution as intermediates of aromatization on HZ5. The C6-C10 distribution was increased by addition of up to 60 wt% of Mn promoter due to the improved dispersion of Fe7C3 and alkyl insertion of MnO. At 340 °C under 20 bar, 97.2% CO conversion and 39.8% aromatics selectivity were achieved by using a physically mixed catalyst of K/FeMn with Mn/(Fe+Mn) 60 wt% and HZ5 with an optimization of the FTS-derived C6-C10 olefin yield as efficient intermediates in Syngas to Aromatics (STA). Plausible scheme for FTS and STA reactions in this study. [Display omitted]