The Efficiency And Mechanism Of Bisphenol A Degradation In SPC System Activated By Copper-based Catalyst

With the development of my country’s society and economy and the technological update of agriculture and chemical industry,more and more refractory organic pollutants are discharged into water bodies and are difficult to remove.Even if the content in the environment is very low,they can cause strong toxicity.Physical effects and ecological hazards seriously threaten the health and safety of human life.Therefore,advanced oxidation technology has become a hot research direction due to its rapid reaction and no secondary pollutant generation advantages.This paper studies the removal efficiency of Cu（Ⅱ）/SPC homogeneous system and CuOOH/SPC heterogeneous system on trace organic pollutants in water,and compares and analyzes the effect of different forms of H₂O₂ on the degradation reaction.Results showed that in the single SPC and single H₂O₂ system,the degradation effect on BPA is not obvious;In Cu（Ⅱ）/SPC system and CuOOH/SPC system,the degradation rate of BPA is higher than Cu（Ⅱ）/H₂O₂ system and CuOOH/H₂O₂ system.The influence of different water quality conditions such as solution pH value,sodium percarbonate concentration,catalyst concentration,initial concentration of pollutants,common inorganic ions and water quality background on the removal of pollutants by the activation system was explored,and the best operation parameter under this experimental condition was determined.In the Cu（Ⅱ）/SPC homogeneous system,the degradation rate of BPA increases significantly with the increase of the concentration of sodium percarbonate,and decreases with the increase of the initial concentration of BPA.When the Cu（Ⅱ）concentration is 1mmol/L,the degradation rate of BPA is the highest.A large number of inorganic ions and soluble organics in tap water and artificial lake water have a certain inhibitory effect on the degradation of BPA.The initial pH of the solution has no significant effect on the degradation of BPA in the Cu（Ⅱ）activated SPC system.In the CuOOH/SPC heterogeneous system,the degradation rate of BPA increased significantly with the increase of SPC concentration and CuOOH dosage,and decreased with the increase of initial BPA concentration.The catalytic activity of CuOOH in deionized water is slightly higher than that of artificial lake water and tap water.The initial pH of the solution is both acidic and alkaline,and BPA has a good degradation effect.Among the common ions in water,Ca²⁺,K⁺and PO₄^3-have a certain inhibitory effect on the degradation of BPA in the CuOOH activated SPC system.Compared with the Cu（Ⅱ）/SPC homogeneous system,the CuOOH/SPC heterogeneous system can effectively remove the precursors of the conventional disinfection by-products,and has the ability to reduce and control the generation potential of the disinfection by-products.The generation of free radicals and non-radical active oxide species during the oxidation of organic pollutants in the activated SPC system was studied,and the oxidation reaction mechanism of the sodium percarbonate reaction system was explained.The free radicals produced by the reaction system were determined by ESR and FD.Two free radicals,·OH and O₂·^-were detected in the Cu（Ⅱ）/SPC system,while·CO₃^-and ¹O₂ were not detected.The generation rate of hydroxyl radical was the highest at 30min,and the reaction was basically stagnant and the cumulative amount didn′t increase after 30min.Two free radicals,·OH and·CO₃^-were detected in the CuOOH/SPC system,but O₂·^-and ¹O₂ were not detected.The generation rate of hydroxyl radicals in the CuOOH/SPC system increases significantly with the increase of time,and the relative generation of hydroxyl radicals in the CuOOH/SPC system is higher than that in the Cu（Ⅱ）/SPC system.The generation rate and amount of various oxidative free radicals under neutral conditions are significantly higher than those of acidic and alkaline.Therefore,the homogeneous Cu（Ⅱ）/SPC system and the heterogeneous CuOOH/SPC system both show the best decontamination efficiency under neutral conditions.