Preparation of nano-hollow sphere hydrolytic catalyst and study on its COS removal performance

Micro-nano hollow materials have become a research hotspot due to their unique structure and properties. Blast furnace gas is one of the main pollutants discharged from steelmaking, and the COS chemical property in blast furnace gas is stable, which is difficult to be effectively removed. Nano-hollow sphere composite has the advantages of large specific surface area, adjustable material size, and stable performance. It has become one of the most promising hydrolysis catalytic materials due to its good catalytic performance. In this study, the template of carbon spheres was synthesized by the glucose hydrothermal method, and activated aluminum nitrate was loaded on carbon sphere templates by the method of equal volume impregnation. Urea was used as precipitant to prepare uniform Al₂O₃ hollow sphere hydrolysis catalyst, and its application and removal performance in COS removal of blast furnace gas was explored. The results showed that (1) When the ratio of water to alcohol was 30 mL:90 mL and the calcination temperature was 950 ℃, the particle size of the prepared γ-Al₂O₃ hollow sphere hydrolysis catalyst was between 100 and 150 nm, the average pore size was 6.785 nm, the total pore volume was 0.259 cm³·g⁻¹ and the specific surface area was 154.665 m²·g⁻¹. (2) When the roasting temperature is 950 ℃ and the addition amount is 40 mmol, the hydrolysis catalytic efficiency of COS is the highest. After the reaction for 70 min, the hydrolysis catalytic efficiency is maintained at about 68%, and the conversion amount is 120 mg·m⁻³.