Flow-through Fenton-like Reaction Assisted By Electric Field Toward Effective Organic Micropollutants:Performance And Mechanism

In recent years,electrochemical Fenton-like technology has attracted extensive attention because of its simple operation,mild reaction conditions,green and high efficiency.However,the technology still has some problems,such as narrow pH range and poor catalyst stability.In order to solve the above problems,we design and develop two kinds of penetrating Fenton-like technologies based on electrically activated carbon nanotubes（CNT）thin films,which effectively widened the applicable pH range and improved the stability of catalysts.The preparation,characterization,performance testing and mechanism analysis of nanocomposite membranes have been studied successively.The specific research contents are summarized as follows:（1）The electroactive CNT filter membrane co modified by iron and molybdenum disulfide（Fe-MoS₂@CNT）is prepared by hydrothermal method.Under the action of auxiliary electric field,CNT catalyzes the two-electron reduction reaction of dissolved oxygen in water to generate H₂O₂in situ.Fe catalyst catalyzes the decomposition of H₂O₂ to produce highly active species hydroxyl radical（HO^·）.MoS₂ acts as a cocatalyst to further improve the decomposition rate of H₂O₂.The auxiliary electric field not only induces the two-electron reduction reaction of dissolved oxygen,but also accelerates the cycle of Fe³⁺/Fe²⁺redox pair.This design realizes the efficient removal of emerging pollutants represented by tetracycline.The results showed that 95%degradation rate of tetracycline could be achieved within 60 min under the conditions of Fe doping of 0.3 m M,applied voltage of-2.5 V and flow rate of 6 m L/min.The operating parameters such as voltage and flow rate have significant influence on the degradation kinetics of tetracycline.HO^·was confirmed to be the dominant active species in the system by free radical trapping experiments and electron paramagnetic resonance spectroscopy.（2）Thin SnO₂ nanoparticles are grown in situ on the surface of CNT by an electrosorption-hydrothermal process.Based on this,we design a new process based on the activation of persulfate（PMS）by electroquinone intermediates for water purification and electrode anti-pollution.Under the action of the auxiliary electric field,the aromatic organic pollutants represented by aniline can be oxidized to quinone organic intermediates at the anode.Quinone intermediates can react with PMS in solution to form oxidizing singlet oxygen（~1O₂）.~1O₂is selective to aromatic electron-rich groups and can further oxidize the parent organic pollutants and intermediates,thus effectively alleviating the adsorption and deposition of polymer organic intermediates on the electrode surface.In addition,the system has significant degradation effect on various types of pollutants and practical printing and dyeing wastewater,and pH has a wide range of applications.