Are hierarchical zeolites good catalysts for Methane Dehydroaromatization? A critical analysis

The socioeconomic dependence on natural gas must be reduced to comply with the stricter carbon emissions requirements. However, avoiding natural gas from the future energy mix is easier said than done. To bridge this gap, lignocellulosic biomass-derived biomethane (aka. “renewable natural gas”) represents an elegant solution to this contemporary problem. Owing to the increased industrial interest in hierarchically structured zeolites for biomethane valorization, through this work, we explore the technical feasibility and challenges associated with methane dehydroaromatization over Mo-loaded on both microporous and hierarchical zeolite ZSM-5. Hierarchical zeolites were prepared using inexpensive and environmentally benign glucose as a secondary organic structure directing agent, leading to two shapes (coffins and hexagonal bars) with comparable physicochemical properties. Although a similar catalytic performance was obtained over (nano-sized) microporous and hexagonal bar-derived zeolites, coffin-shaped zeolite catalysts led to lower activity and slower deactivation. Herein, catalyst deactivation was governed by inter- and intra-particle diffusional properties.