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for optimal performance


COS hydrolysis catalyst

CKA-3 is a promoted alumina-based catalyst used for hydrolysis of carbonyl sulfide (COS).

The CKA-3 catalyst has a high activity even at low temperatures, which is essential for maximum conversion of COS, as the chemical equilibrium is favorable at low temperature.

Whether the end product is chemicals or power, hydrolysis of carbonyl sulfide can be used in some gasification based plants to provide a more optimal process layout.

In the COS hydrolysis reaction, the carbonyl sulfide is converted to hydrogen sulfide and carbon dioxide, which are easier to remove in the Acid Gas Removal (AGR) unit. As a result, the cost and size of the AGR can be reduced, which leads to significant savings.

COS hydrolysis in combination with sour shift

The SSK-10 sour shift catalyst is active towards COS hydrolysis, but the conversion will be limited by the equilibrium at the outlet of the sour shift section. If further reduction of the COS content is required, the CKA-3 catalyst can be used for treating the shifted gas and/or the gas bypassing the sour shift section.