Abstract: A new desulphurizer was developed.It is a dual system which contains mainly TEA as Fe(3+)complexing agent citric acid as Fe(2+) complexing agent.The research work included selection of desulphurizer,model test.effect of sub-reaction on organic sulphur (COS) absoption and corrosion test.It is indicated that the new desulphurizer has many advantages such as high efficiency, high sulphur absorption capacity,stability,low cost,low corrosion and little sub-reaction.