One-Pot Synthesis of N Doping Al2O3 Catalyst for Efficient Hydrolysis of COS

Catalytic hydrolysis was regarded as the most feasible technology of removing carbonyl sulfide (COS) from blast furnace gas (BFG) or coke oven gas (COG). However, the current hydrolysis catalysts were deactivated due to sulfur species deposition. In this paper, N doping Al₂O₃ catalysts were successfully synthesized by one-pot method, which could achieve 98% COS conversion efficiency and 90% H₂S selectivity under 70 °C after 24 h reaction. The characterization revealed that nitrogen doping could increase the specific surface area, pore size and pore volume of Al₂O₃ catalysts. Especially, the average pore diameter of N doping Al₂O₃ catalysts was broaden from 2 to 13 nm to 2–17 nm. Moreover, N doping was beneficial to pyridine nitrogen formation, which promoted Lewis basic sites and the number of hydroxyl groups. Thus, the active oxygen in the catalysts were consumed and sulfur species deposition was suppressed. COS conversion efficiency and lifetime of N doping Al₂O₃ catalysts were increased. This study provides a new COS hydrolysis catalyst with higher activity and stability, offering promising potential for the commercial application.