Fig. 5 shows the removal of color and COD at different reaction time by Fenton process. The FeSO4 and H2O2 dosage were fixed at 120 mg/L and 150 mg/L, respectively. The pH was controlled at 4.0. As the reaction time increased, the color and COD removal increased sharply during the first 60 min and increased slowly afterwards. The removal of COD was more than 80.4% after reaction 60 min, simultaneously, there was more than 88.4% of color removal. On the one hand, Fenton oxidation of organic compounds showed that the initial rate of mineralization was fast with Fenton reagents, due to the immediate formation of hydroxyl radicals in the case of Fenton reagent, thereby the color and COD could be reduced obviously. On the other hand, it demonstrated that the recalcitrant organic chemicals which was in the wastewater had been oxidized by HOradical dot after reaction 60 min, resulting in the curve slightly ascending [22]. In Fenton oxidation system, the produced hydroxyl radicals which had extremely high oxidizing ability and could oxidize hard to decompose organic compounds in a short time. However, as for the actual Fenton process, the degradation of the pollutants could yield lots of side reactions. That is, the actual operational time need be selected at the long time range. Hence, the operational parameter of reaction time was chosen as 60 min.