Transalkylation between C10 aromatics and 2-methylnaphthalene to synthesize 2,6-dimethylnaphthalene by Mo-modified HZSM-12 catalysts

Abstract

Zeolites are important catalysts for the synthesis of 2,6-dimethylnaphthalene (2,6-DMN) by the raw materials of 2-methylnaphthalene (2-MN) and C₁₀ aromatics. However, the selectivity of 2,6-DMN is still difficult to control and the catalysts often suffer from poor hydrothermal stability. In this work, a series of Mo-modified HZSM-12 catalysts were prepared and investigated for the transalkylation reaction between 2-MN and C₁₀ aromatics under a hydrogen atmosphere. The introduction of Mo binds to the B-acid sites on the molecular sieves, modulating the B-acid strength and content of the catalysts while also altering their pore structure. As a result, the 3 %Mo/HZSM-12 catalyst exhibited excellent catalytic performance, the conversion of 2-MN could still reach up to 61.3 % and the ratio of 2,6-/2,7-DMN was able to reach 1.69 after 6 h of the reaction. Therefore, our work is expected to provide a useful strategy for constructing efficient zeolite catalysts for the synthesis of high-value esters’ precursors.