Synergic effect of Zn and Cu oxides dispersed on activated carbon during reactive adsorption of H2S at room temperature

[object Ohe origin of the synergic effect of zinc and copper oxides (ZnO-CuO) supported onto activated carbon on the removal of hydrogen sulphide (H2S) from gaseous streams at low temperature is investigated in this work. Sorbents with a fixed total metal content and variable Zn:Cu ratios were prepared by impregnation of a commercial activated carbon. H2S (100-3000 ppmv in N2) removal tests were run under dynamic conditions at 30 °C and compared through analysis of their breakthrough curves, adsorption rates and values of adsorption capacity. Fresh and spent sorbents were characterized by BET and pore size distribution via N2-adsorption, SEM-EDX and XPS. TPD/TPO experiments from partially and completely saturated sorbents allowed the speciation of adsorbed sulphur species, testifying the complexity of the surface reactions which strongly depended on the Zn:Cu ratio, on the interactions of metal oxides with activated carbon and on the textural properties of the sorbent.bject]