The conversion of syngas to aromatics over composite catalysts, comprising a mixture of Fe2O3-SiO2 and Nb-/Ni- modified HZSM-5 (HZ), CuO-ZnO-Al2O3 (CZA) and Nb-/Ni- modified HZ, and a mixture of above two kinds of metal oxides and Ni-HZ, were investigated at 330 °C, 4 MPa and H2:CO = 2:1. Catalysts were characterized to analyze the properties. Fe2O3-SiO2/modified-HZ had the high selectivity of BTX, while CuO-ZnO-Al2O3/modified-HZ had the high selectivity of durene. Fe-CZA/Ni-HZ exhibited higher selectivity of trimethylbenzene (triMB) than both Fe/Ni-HZ and CZA/Ni-HZ, lower selectivity of BTX and tetramethylbenzene (tetraMB), compared with Fe/Ni-HZ and CZA/Ni-HZ, respectively. Reaction pathways were speculated to illustrate the diverse distribution of aromatics. The incorporation of Nb and Ni on the parent HZSM-5 increased the selectivity of aromatics due to their various acidity. The highest selectivity of BTX was obtained over Fe/Ni-HZ and the highest selectivity of durene was achieved over CZA/Nb-Ni-HZ.

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Aromatics produced from syngas have been attracting much more attention in recent years. In this study, the K-modified FeMnO/​MoNi-ZSM-5 catalyst was used in the one-step conversion of syngas to aromatics. The effects of K loading contents on the catalytic activity and the stability of the FeMnO/​MoNi-ZSM-5 catalyst were investigated. In addition, the conversion of CO and the selectivity of the products were analyzed. XRD, EDS, TG, XPS, and BET were carried out to characterize the properties of the catalysts before and after reaction. It can be investigated that the loading of K promoted the CO adsorption performance and the carburization of iron oxide on the catalyst, which increased the stability of the catalyst and inhibited the formation of CH4 and CO2.