Highly selective upgrading alkane into light aromatics via a Low-Concentration O2 coupling reaction strategy

Transforming alkanes into value-added light aromatics represents an promising strategy for maximizing the utility of fossil feedstocks. However, achieving highly selective aromatization reactions remains a formidable challenge. This study advocates for an alkane-O 2 coupling reaction strategy, which involves introducing a low-concentration O 2 atmosphere into the reaction system to facilitate the upgrading of alkanes to value-added aromatics over HZSM-5 zeolite catalyst. The investigation revealed that the abundant acidic sites on the zeolite facilitated alkane activation and subsequent C–C and C–H bond cleavage. Incorporating O 2 into the reaction generated oxygenated intermediates, significantly enhancing both the yield and selectivity of light aromatics compared to an inert atmosphere. Furthermore, the interaction of O 2 with coke bolstered the catalyst’s resistance to coking. Moreover, based on the in-situ FTIR results, a plausible alkane-O 2 coupling mechanism is proposed. These findings present a novel, effective, and environmentally benign approach for the highly selective aromatization of alkanes.