Iranian Journal of

Backgrounds and Objective: Surfactants are one of the largest pollutants which exist in urban and industrial wastewaters. Large quantities of surfactants have entered to the environment since last decade due to increased use of synthetic detergent in industrial and home consumptions.In this study, the efficiency of UV/H2O2 process in removal of linear alkylbenzane sulfonate (LAS) from aqueous solutions was investigated.
Materials and Methods: In this study methylene blue active substane(MBAS)method and spectrometery were used to determine anion and residual surfactant respectively. In this study important variables were H2O2 concentration, initial concentration of surfactant, pH and duration of UV radiation. The effect of UV/H2O2 process on the degradation of LAS was analyzed statistically by using Multiple Linear Regression test.
Results: The resulted showed that after 20 minute, ultraviolet radiation solely removed 38.44 percent of Anionic detergent, Hydrogen peroxide showed no significant removal of detergent solution in the time course study. The efficiency of UV/H2O2 process in 10, 20 and 30 minute were to 86.2, 90 and 96.5 %, respectively.
Conclusion: The results showed that the efficiency of ultraviolet radiation and hydrogen peroxide process in anionic detergent was not significant thoogh it was considerable in combination process (UV/H2O2).

Background and Aim: In this study, the removal of dye blue reactive-171 by combination of advanced oxidation processes UV/H₂O₂ and SBAR has been investigated. Methods: The efficiency of chemical and biological system was first investigated separately. In chemical system, the kind, power, initial dye concentration and hydrogen parasitize and in biological system, hydraulic detention time, aeration rate, initial dye concentration and the percent removal of dye and COD were investigated. In order to investigate the hybrid system, after determination of the optimum conditions and the capabilities of each system, the removed chemical system effluent from residual hydroxide peroxide, was entered into the biological reactor. Results: In the chemicals process, 100 ppm dye using 150 Watt-UV-C lamp and 0.1 mM hydrogen peroxide at pH= 9 was completely removed in 25 minutes. COD removal was 86.7 percent at the end of the experiment (135 min). Biological system with adsorption mechanism has shown 44 percent dye removal with initial COD of 50 mg/L that indicated the system inability in biodegradation and breaking down of the dye molecule. In comparison to separate chemical and biological processes, hybrid system has shown better dye removal efficiency. The results indicated that in addition to the complete dye removal achievement, 81% of COD in the first hybrid system and 52% of COD in the second hybrid system was removed, respectively. Conclusion: According to the results, because of complexity of dye structure, biological system was not able to remove the dye as efficient as hybrid system of advanced oxidation processes UV/H₂O₂ with SBAR.