Hydrogen sulfide adsorption and oxidation onto activated carbon cloths: Applications to odorous gaseous emission treatments

The objective of this study was to suggest mechanisms and to quantify activated carbon cloth capacities in the removal of hydrogen sulfide present in air. Several parameters affect the H2S treatment capacity of activated carbon. These include the physicochemical surface characteristics and the operating conditions. Four activated carbon cloths and a granular carbon were used in a batch reactor for their deodorization abilities toward hydrogen sulfide. Different parameters such as the level of humidity, the presence of oxygen in the gas phase, and the structural and chemical surface properties of the adsorbents have been studied. Kinetics and equilibrium isotherm curves were performed and modeled. The results showed that hydrogen sulfide loaded onto activated carbon develops chemical reactions. The different byproducts from the H2S oxidation have been identified and quantified. Mass balance of sulfur compounds has been performed. The hydrogen sulfide removal was found to be produced mainly by oxidation reactions on specific surfaces. An approach of the oxidation pathway has been determined and depended on the operating conditions and surface functional groups present on the intrafiber surface. The catalytic role in H2S treatment played by the sulfur So byproduct from the oxidation reaction is shown. These results reveal the high treatment capacities of the activated carbon cloths in hydrogen sulfide removal.