CuFe2O4/activated carbon adsorbents enhance H2S adsorption and catalytic oxidation from humidified air at room temperature

A variety of CuFe2O4-based adsorbents with different active phase loadings were synthesized to remove H2S from humidified air at room temperature. The materials were characterized by adsorption of nitrogen, SEM-EDX, XPS, XRD, and TGA. According to the results, the activated carbon with 20 wt% CuFe2O4 exhibited the best H2S adsorption performance, reaching 292 mg/mL (667 mg/g). Furthermore, the H2S adsorption capacity reduced by 7% after two cycles of thermal regeneration. During the desulfurization process, FeOOH formed as an intermediate played a catalytic role. The products comprised sulfide, elemental sulfur, and sulfates. Elemental sulfur was the predominant product. The H2S removal involved both reactive adsorption and catalytic oxidation. In addition to the chemical properties of the active phase, structural characteristics like pore volume also determined the adsorption capacity. Pore volume of less than 6 nm pores could enhance catalyst dispersion, provide adsorption centers and store the oxidation products. This study will offer novel insights for the efficient synthesis of metal oxide-based adsorbents and the extensive application of their reactive adsorption capacity at the nanoscale level.