Remove Of Atrazine In Sulfate Radical Based Oxidation Processes

Sulfate radical(SO4-) based advanced oxidation process(AOPs) have a good application prospect in the field of wastewater treatment due to the strong oxidizing ability of SO4-, The generally used activation ways include light, heating, microwave irradiation and by using transition metal ions as activators.The removal of ATZ by heat activated persulfate and Co2+/PMS system were systematically studied in this work. In present study, factors influenceing the degradation were investigated. MS (Mass Spectrometry) was applied to identification of degradation products and according to the results of MS. Possible degradation pathways and degradation products for atrazine were determined.It was demonstrated that the degradation of ATZ was a second-order reaction. In Both of the two systems the removal of ATZ were viable at a wide range of pH (3.0-10.0), although slightly less efficient at basic condition than acidic and neutral given other conditions identical. Radical scavenger test indicated that OH-was the predominant radical species at basic condition while SO4- played a critical role at neutral and acidic conditions. In both of the two systems, The removal of ATZ was slightly inhibited in the presence of HA and CO32- of both systems. Cl- showed a complicated effect on the removal of targeted pollutant of both systems. When Cl- was less than 10 mmol·L-1, it promoted the degradation. However, at higher concentration, it compete oxidants thus reduced the removal efficiency of ATZ.ATZ degradation products and reaction mechanism in the two systems were studied by MS. The results show ATZ in the degradation process mainly produces HA、DIA、EA、 HA、IA、DEA、DEIA. DEHA and DEIHA within 2 h in Co2+/PMS system. Besides these products, DIHA and cyanuric acid were also found in heat activated persulfate system within 2 h. In addition, the main degradation pathways proposed inclued dealkylation, dechlorination and alkylic-oxidation.