Abstract: Almost all the catalytic cracking desulfurizing units ill China have been using ethanolamine as the solvents in wet desulphurization for many years.The solvents in most units arc seriously contaminated.while they can't be discharged frcely under enviroment protection, resulting in loss of activity and worsening of desulphurization effects. A new desulfrizer (YXS - 93) is introduced in this paper which has been in use in Louyang Petrochemical Complex.The new desulfrizer was mixed with the ethanolamine in the unit at first and then replaced the ethanolamine gradually. The new desulfurizer , which shows good desulphurization effects and a large decrease in H2S contents in desulfurized dry gas, has the advantages of low corrosion and stable properties.