NON-OXIDATIVE METHANE CONVERSION STUDY ON GRANULATED Mo-CONTAINING ZEOLITE CATALYSTS

The results of the study of the influence of the method of forming granular Mo-containing zeolite catalysts on their physicochemical and catalytic properties in the process of non-oxidative conversion of methane are presented. There is shown a higher catalytic activity of granular catalysts with a hierarchical porous structure, obtained without using binders, compared to a granular catalyst obtained by a conventional method of mixing powdered zeolite with pseudobemite, followed by granulation and calcination. The texture and acid characteristics of granulated zeolites and Mo-containing catalysts based on them have been studied. The effect of dealumination of granular zeolites with a hierarchical porous structure on their texture and acid characteristics, as well as on their catalytic activity in the process of methane conversion is shown. The HRTEM method shows a difference in the distribution of the active Mo-containing phase in the granulated zeolite catalysts depending on the method of their preparation. Particles with a wide size distribution (2-30 nm), which are the crystalline phase of molybdenum carbide (β-Mo2C), and Mo-containing clusters in zeolite channels are present on the surface of granular samples that do not contain a binder. The catalyst prepared with the addition of the binder is micron agglomerates consisting of sub-micron sized zeolite particles and alumina sufficiently uniformly covering the surface of the zeolite. According to elemental mapping using energy dispersive X-ray spectroscopy, it was found that the active component is uniformly distributed over the catalyst surface, but the molybdenum signal on the alumina is significantly higher, which is explained by its higher specific surface area and the availability of particles. It has been found that the method of preparing granular Mo-containing zeolite catalysts has an effect on their catalytic activity, selectivity and stability in the process of non-oxidative conversion of methane to aromatic hydrocarbons. For citation: Stepanov A.A., Korobitsyna L.L., Vosmerikov A.V., Gerasimov E.Yu., Ishkildina A.Kh. Non-oxidative methane conversion study on granulated Mo-containing zeolite catalysts. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 8. P. 85-94. DOI: 10.6060/ivkkt.20246708.7t.