Research into the reaction process and the effect of reaction conditions on the simultaneous removal of H2S, COS and CS2 at low temperature

Abstract

In this work, tobacco stem active carbon (TSAC) catalysts loaded on to CuO and Fe₂O₃ were prepared by a sol–gel method and used for the simultaneous removal of hydrogen sulfide (H₂S), carbonyl sulfide (COS) and carbon disulfide (CS₂). The influences of the operating conditions such as reaction temperature, relative humidity (RH), O₂ concentration, and gas hourly space velocity (GHSV) were discussed. DRIFTS results showed that the deactivation was attributed to the generation of S and sulfates. H₂O promoted the generation of sulfate. The enhancement of the hydrolysis of COS/CS₂ was due to the promotion of H₂S oxidation by O₂. A high GHSV decreased the contact time between the gases and the catalyst. Meanwhile, a high GHSV was not conducive to the adsorption of gases on the surface of the catalyst. XPS results indicated that the deactivation of the catalyst was attributable to the formation of S containing components, such as thiol/thioether, S, –SO– and sulfate. BET results indicated that the adsorptive ability of the catalyst was related to the microporous volume and surface area.