Background and Aim: Discharge of Wastewater of Cleaning Industries to environment with special physicochemical characteristics has negative effects and in the other hand is not easily biodegradable because in these wastewaters ratio BOD5/COD is low and therefore biological treatment of them is difficult. Nowadays best method for degradation of Wastewater is advance oxidation processes .In this study investigated efficiency of Fenton process in remove anionic detergent and COD and improved from ratio of BOD5/COD.

Materials and Methods: This investigating is descriptive- empirical study that paksan factory was local sampling of wastewater. 30 wastewater composite sample24hr were taken during study period and then chemical characterization was performed by determining the following parameters: (COD, BOD, MBAS, PH, T) Then Sample of row wastewater were prepared and used in the experiments for determining the efficiency of Fenton process in treatment. Treatment experiments performed by use of various concentrations of H2O2 and ferrous iron at constant pH of 3and temperature of 25 in a jar test apparatus adjusted at 200 rpm and for contact time 60 min. Fe+2 on removal (COD, MBAS & BOD ) applied ANOVA. and after that for analysis of effect H2O2

Results: The results of analyze showed that the concentrations of COD, ranging from 6254-13040 mg/l and concentration of BOD was 2590-3200mg/l and concentrations of MBAS were 245-1120 mg/l and results showed that the BOD5/COD ratio was 0.34±0.09. At constant pH of 3 and temperature of 25 for contact time 60 min, about 40% of MBAS with first concentration 470 mg/l removed by H2o2 with concentration1800and fe+2 with concentration 340 mg/l .concentration of COD reduced from 8750 to 5998 mg/l, and the ratio of BOD5/COD improved from 0.334 to 0.340.

Conclusion: Wastewater from this industry has quality characteristics with deferent ranging and high organic load and because of high concentration of foaming that prohibit of oxygen infiltration in wastewater and nonbiodgredable material. These wastewaters are not easily subjected to conversation system of biological treatment; therefore suitable method for treatment of this wastewater should reduce organic load foaming and improve ratio of BOD5/COD advance oxidation process is one method with good efficiency for treatment of this wastewater.