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, sulfur species deposition would shorten the lifetime of the catalyst. In this paper, N doped Al ₂ O ₃ catalyst was successfully one-pot synthesized, which could achieve 98% COS conversion rate and 90% H ₂ S selectivity under 70 ^o C after 24 h reaction. The influence of N doping content and operation temperature on the performance of the catalysts were also investigated. The characterization revealed that the doping of nitrogen could increase the specific surface area, pore size and pore volume of Al ₂ O ₃ catalyst. Especially, the average pore size of N doped Al ₂ O ₃ catalyst was broaden from 2–13 nm to 2–17 nm. Moreover, N doping could result in pyridine nitrogen formation, which caused more Lewis basic sites and increased the number of hydroxyl groups. Thus, the active oxygen in the catalyst were consumed and sulfur species deposition were suppressed. COS conversion rate and lifetime of N doped Al ₂ O ₃ catalyst were promoted.