Dual anchoring strategy to construct low metal loading Co/BEA catalysts for propane dehydrogenation†

Abstract

Cobalt-based catalysts have garnered significant attention in propane dehydrogenation (PDH) due to their cost-effectiveness and environmental compatibility, where the properties of Co species dictate catalytic performance. However, conventional synthesis methods fail to simultaneously achieve precise encapsulation and structural stabilization of Co sites under harsh PDH conditions. Herein, we propose an innovative dual-anchoring strategy that synergizes strong electrostatic adsorption (SEA) and secondary crystallization (SC) to engineer highly stable yet active Co centers at low metal loadings (actually 0.125 wt%). The SEA process enables directional anchoring of Co precursors within silanol nests of dealuminated BEA zeolite, while the SC treatment prevents Co aggregation. This synergistic approach yields tetrahedral Co²⁺ (T_d-Co²⁺) sites with exceptional dispersion and optimized Lewis acidity, which achieved ultra-long PDH stability of up to 110 hours and specific activity surpassing most reported catalysts.