In this study, the oxidation of SO 2 on activated carbon (AcC) by using distilled water and air was carried out in a laboratory scale trickle bed reactor (TBR). Distilled water and air containing 1.7 % (v/v) SO 2 were fed co-currently downward through a fixed bed of AcC particles in a range of 1±7 cm 3 /s and 10±27 cm 3 /s respectively. H 2 SO 3 /H 2 SO 4 solutions were the products obtained in the liquid phase. Steady-state experiments were performed in a column of 0.15 m packing height and 0.047 m column diameter at 20 C and atmospheric pressure. Experimental reaction rates of this study were compared with those of other studies on the basis of plug flow model of Mata-Smith given in literature.