Single-Step Selective Conversion of Carbon Dioxide to Aromatics over Na-Fe3O4/Hierarchical HZSM-5 Zeolite Catalyst

The conversion of carbon dioxide (CO2) to value-added chemical compounds that can be used as precursors in many industrial processes is a very attractive approach to facilitate greenhouse gas reduction. Here, we demonstrated a high-efficiency bifunctional catalyst composed of sodium-modified Fe3O4 and hierarchical nanocrystalline HZSM-5 aggregates, which could prepare aromatics from CO2 with a high yield of 23.5% and CO2 conversion of 45.3% at the space velocity of 4000 mL/gcat/h. The results showed that the low proximity of the two components, a suitable mass ratio of iron/zeolite, and a high density of total acidity over the bifunctional catalyst are decisive factors for the high selectivity toward aromatics and high catalytic stability. This study provides a simple and efficient way for direct CO2 hydrogenation to aromatics.