Abstract

Cu–1,3,5-benzenetricarboxylate (Cu–BTC) exhibited potential for hydrogen sulfide (H₂S) removal, however, its sulfur capacity is limited due to it relies only on the adsorption reaction path. Herein, a series of Fe-doped Cu–BTC materials (denoted as xFe–Cu–BTC) were synthesized to enhance H₂S removal capacity via a adsorption–oxidation bifunctional synergism mechanism. The prepared materials were characterized using various techniques, and their H₂S removal performance was measured under dry and ambient conditions. The experimental results demonstrated that the 18?%Fe–Cu–BTC shown the optimal breakthrough sulfur capacity of 122.8?mg S/g, marking a 2.1-fold and 10.3-fold improvement over pure Cu–BTC and Fe–BTC, respectively. The characterization analyses revealed that the Cu²⁺ active sites initially react with H₂S to form CuS, while the incorporated Fe³⁺ sites trigger the oxidation of CuS, yielding elemental sulfur, Cu²⁺ and Fe²⁺. The resultant Cu²⁺ and Fe²⁺ further engage in reactions with H₂S to form CuS and FeS, thereby enhancing the H₂S removal capacity via dual reaction pathways of adsorption and oxidation. Additionally, appropriate Fe doping increased the specific surface area and pore volume of Cu–BTC, which exposed more active sites and improved molecular diffusion. Based on the obtained findings, a plausible desulfurization mechanism involving adsorption and oxidation synergism for remove H₂S was proposed.