Absorption and desorption of SO_2 by polyamine compounds in aqueous solution

The effects of diethylenetriamine,triethylenetetraamine and tetraethylenepentaamine on the absorption and desorption performance of SO2 were investigated.And diethylenetriamine was screened out as the absorbent.The desorption rate of diethylenetriamine solution can be enhanced effectively by adding citric acid.The optimum technological conditions for the absorption and desorption of SO2 with diethylenetriamine/citric acid solution are as follows: the concentration of diethylenetriamine is 0.2 mol/L,the pH value of the absorption solution is 5.40,the absorption temperature is 40 ℃ and the desorption temperature is 102 ℃.Under such conditions,the maximum absorption of 2.65 mol/mol is achieved with the desorption rate of 90.57% and the oxidation rate of 3.77%.