Catalytic hydrolysis of carbonyl sulfide over Ce-Ox@ZrO2 catalyst at low temperature

The high applicable temperature, poor low-temperature activity and stability of current carbonyl sulfur (COS) hydrolysis catalysts greatly restrict their application in the field of blast furnace gas desulfurization. Various metal oxide carriers and rare earth oxide active components to modify the composition of catalysts. By incorporating Ce, the catalytic performance and H2S selectivity of the modified catalysts were extensively investigated. The 15%Ce-O-x@ZrO2 catalyst achieved a COS conversion of 80.5% and an H2S selectivity of 80% at 90 degrees C. Even after 7 h of reaction, the preferred catalyst maintained a COS conversion rate above 80%. Characterization results indicated that the addition of Ce effectively increased the specific surface area of the catalyst, thereby enhancing the adsorption, diffusion and reaction of reactant molecules on its surface. Furthermore, as the loading of Ce increased, the strength of the weak base centers gradually intensified, while the amount of acid on the catalyst surface significantly decreased. These weak base sites play a vital role in the hydrolysis reaction, which ultimately accounts for the exceptional low-temperature hydrolysis performance of the 15%Ce-O-x@ZrO2 catalyst. This study provides a theoretical basis for the preparation of rare earth catalytic materials for COS hydrolysis catalysis.

Automated summary

The current carbonyl sulfur (COS) hydrolysis catalysts have limitations in terms of high applicable temperature, poor low-temperature activity, and stability, restricting their application in blast furnace gas desulfurization. This study investigates the modification of catalyst composition by incorporating Ce, leading to enhanced catalytic performance and H2S selectivity. The addition of Ce increases the specific surface area of the catalyst, improving the adsorption, diffusion, and reaction of reactant molecules. The presence of weak base sites plays a vital role in the hydrolysis reaction, explaining the exceptional low-temperature hydrolysis performance of the modified catalyst.