Effect of the introduction of niobium carbide on non-oxidative dehydro-aromatization of methane over MoMCM-22

Abstract

The effect of the introduction of niobium carbide was studied on the dehydro-aromatization of methane over a molybdenum containing HMCM-22 zeolite at 973 K. The introduction of niobium decreased Bronsted acidity, affecting catalyst behavior on the dehydro-aromatization of methane. Niobium carbide containing zeolite showed lower activity, lower coke deposition and predominant formation of naphthalene, in the expenses of benzene, the major product observed for Mo containing zeolite. Besides carbidic carbon, two other types of coke were observed: one associated to molybdenum and the other associated to Bronsted acid sites located both on the catalyst surface and inside zeolite pores.