Effect of Catalyst Composition on catalytic hydrolysis of COS

A series of catalysts with various Co/Ni and M²⁺/M³⁺ mole ratios were prepared by decomposition of Co/Ni/Al hydrotalcite-like compounds(HTLcs) precursors at 350°C and used for hydrolysis of carbonyl sulfide(COS). The effect on the catalytic performance was investigated at 50°C and GHSV of 1000~3000 h^-1 with relative humidity of 2.40%. The catalyst with Co/Ni at 0.25~0.5 and M²⁺/M³⁺ at 2~3 had the best activity. The Co/Ni content barely affected the phase composition of the catalysts. The results may indicate that the Ni ion is the catalytic center, while the Co ion is the catalyst accelerator. From the SEM-EDAS analysis, the structures of catalysts with different M²⁺/M³⁺ changed a lot and the various metal ions in samples were consistent with the raw material.