Abstract: The absorption kinetics of carbonyl sulfide in aqueous solution of Fe(Ⅲ)-EDTA was studied by using a gas-liquid double mixing gradientiess contactor. The effects of absorption temperature, interface concentration of carbonyl sulfide, the pH of solution and the concentration of Fe(Ⅲ)-EDTA on the absorption rate of carbonyl sulfide in aqueous solution of Fe(Ⅲ)-EDTA were examined. The experimental results showed that the absorption rate was controlled by the hydrolysis reaction rate of carbonyl sulfide in liquid phase. Under the experimental conditions, the absorption rate can be expressed by the following equation: where the dimension of NA is mol/(m2·s). According to the experimental results and Pearsons general principle of reaction for soft and hard acids and bases, feasible plans for improving the performance of carbonyl sulfide absorption in aqueous solution of Fe(Ⅲ)- EDTA were proposed.