ROLE OF H2O AND O2 DURING THE REACTIVE ADSORPTION OF H2S ON MgO/AC AT LOW TEMPERATURE

H2S reactive adsorption on MgO, CuO, ZnO dispersed onto activated carbon is investigated in different gas streams, containing either N2, or O2/H2O, at room temperature and in a lab-scale fixed-bed reactor. Sorbents performances are analyzed in terms of H2S adsorption capacity and adsorption rate and data are correlated with the sulphur species formed upon adsorption and in the different experimental conditions. Temperature Programmed Desorption (TPD), porosimetric and XPS analyses are performed in order to support the adsorption dynamic tests. The presence of O2 and H2O determines a remarkable increase in H2S adsorption capacity, favouring the formation of different sulphur species such as sulphides, sulphates and, above all, elemental sulphur.