Simultaneous removal of hydrogen sulfide and carbonyl sulfide from various sulfur-containing gases: a review.

Hydrogen sulfide (H2S) and carbonyl sulfide (COS) commonly coexist in fuel gases, chemical product gases, and industrial off-gases, and are characterized by high toxicity and strong corrosiveness. Conventional step-by-step removal processes are lengthy and costly. This review summarizes technologies for the simultaneous removal of H2S and COS, including adsorption, absorption, multiple catalytic pathways, dielectric barrier discharge, and biological treatment. Current studies indicate that metal-modified adsorbents can achieve efficient simultaneous removal through surface sulfidation reactions, although their application is constrained by sulfur capacity; mixed absorbents are suitable for complex gas purification scenarios, but insufficient solvent selectivity and high energy consumption remain key limitations; bifunctional catalysts show considerable promise for low-temperature deep desulfurization, but their active sites are prone to deactivation due to the deposition of sulfur-containing products; combination of adsorption and catalysis is applicable to H2-containing high-temperature feed gases, although their removal efficiency is readily affected by coexisting gaseous impurities.