Research progress on adsorption and separation of carbonyl sulfide in blast furnace gas

The iron and steel industry is one of the foundational industries in China. However, with the introduction of energy-saving and emission reduction policies, desulfurization of blast furnace gas (BFG) is also necessary for further sulfur control in the iron and steel industry. Carbonyl sulfide (COS) has become a significant and difficult issue in the BFG treatment due to its unique physical and chemical properties. The sources of COS in BFG are reviewed, and the commonly used removal methods for COS are summarized, including the types of adsorbents commonly used in adsorption methods and the adsorption mechanism of COS. The adsorption method is simple in operation, economical, and rich in types of adsorbents and has become a major focus of current research. At the same time, commonly used adsorbent materials such as activated carbon, molecular sieves, metal-organic frameworks (MOFs), and layered hydroxide adsorbents (LDHs) are introduced. The three mechanisms of adsorption including π-complexation, acid-base interaction, and metal-sulfur interaction provide useful information for the subsequent development of BFG desulfurization technology.