Methane aromatization on Zn-modified zeolite in the presence of a co-reactant higher alkane: How does it occur?

By using 13C solid-state NMR and GC–MS, the analysis of the 13C-label transfer from methane-13C into the products of methane and propane co-aromatization on Zn/H-BEA zeolite at 823–873 K has been performed. A high degree involvement of 13C-carbon atoms of methane into aromatic products (benzene, toluene, xylenes) has been demonstrated. The main pathway of methane conversion into aromatics has been determined to consist in the methylation of aromatics, which is produced exclusively from propane, by methane. The methoxy species formed by the dissociative adsorption of methane on ZnO species of the zeolite is responsible for the methylation.