Abstract: The effect of desulfurization solvent for hydrogenation tail gas of Claus sulfur recovery process under low pressure was unsatisfactory, which led to higher SO₂ mass concentration in discharged tail gas. To deal with this problem, a new serial of hydrogenation tail gas deep desulfurization solvent CT8-26 was developed and applied on the tail gas treatment unit of Suining Longwangmiao Natural Gas Purification Plant. The results indicated that under the feed gas condition of natural gas purification plant, H₂S mass concentration in desulfurized tail gas could be reduced below 20 mg/m³, and therefore the SO₂ mass concentration in discharged tail gas would be reduced evidently.