Efficiency And Mechanism Of Bisphenol A Degradation Activated By Persulfate With Porous Carbon Supported Cu-Fe Oxides

Emerging organic pollutants such as personal care products are serious threats to water ecological safety and human health.Persulfate activation technology based on transition metal nanooxides has attracted wide attention due to mild reaction conditions and high economy.In this paper,the copper iron oxide nanoparticles on the surface of porous carbon materials in situ load,effectively ease the nanoscale metal oxide in water lead to the problem of low efficiency of catalytic by reunion,the synergy of carbon skeleton and copper iron oxide exposure of the high catalytic site a boost its activation persulfate the performance of the degradation of organic matter and the ability to adapt to the complex environment.In this paper,a comprehensive and systematic study was carried out from the preparation and characterization of catalyst,degradation performance of organic matter,activation mechanism of persulfate and exploration of practical application.The main research contents and results are as follows:（1）Based on the coordination chemistry principle of plant polyphenol tannic acid（TA）and metal ions(Cu²⁺,Fe²⁺),Cu-Fe-TA complex with three-dimensional skeleton structure was synthesized by coprecipitation method,and the porous carbon framework supported Cu-Fe oxide composite catalyst was prepared by roasting it as template.Scanning electron microscopy（SEM）and transmission electron microscopy（TEM）analysis results show that Cu-Fe oxides with particle size of about 140 nm are highly dispersed on the surface of porous carbon.The results of X-ray diffractomer（XRD）,inductively coupled plasma emission spectroscopy（ICP）and X-ray photoelectron spectroscopy（XPS）show that the Cu-Fe oxide is a composite of Cu O and Fe₃O₄.The analysis of vibration samples（VSM）shows that the composite catalyst has certain magnetic separation performance.（2）The experiment of treating endocrine disruptor bisphenol A（BPA）showed that the supported Cu-Fe oxides with porous carbon framework had excellent adsorption performance and strong activation ability of peroxysulfate（PMS）.Under the experimental conditions of catalyst 0.1 g/L and initial concentration of BPA 10 mg/L,BPA could reach adsorption equilibrium within 5 min,the removal rate was 43%.At the oxidation stage,when PMS was 1m M and p H was 7,the removal rate of BPA reached98%within 60 min,and the degree of mineralization was very high,TOC removal rate was close to 60%.The porous carbon framework can not only adsorb organic matter effectively,but also accelerate the electron transfer rate during the activation of PMS and promote the catalytic degradation of organic matter.（3）Chemical quenching experiments and electron paramagnetic resonance（EPR）analysis showed that active oxygen species,such as sulfate radical(SO₄^·-),hydroxyl radical（?OH）and singlet oxygen（¹O₂）,were involved in the degradation of BPA,and¹O₂ played a dominant role.Therefore,the porous carbon supported Cu-Fe oxide/PMS catalytic system showed strong anti-interference ability,and inorganic anions(Cl^-,CO₃^2-,NO₃^-,SO₄^2-)and natural organic compounds（Humic acid,HA）had limited influence on the degradation of BPA.XPS and ATR-FTIR analysis showed that the activation of PMS was realized by the external sphere reaction of Surface Cu（II）and HSO₅^-,and the redox cycle of Cu（II）-Cu（I）-Cu（II）was the key to the activation of PMS to produce reactive oxygen species（ROS）.（4）The results of continuous flow degradation column experiment with different water base materials showed that the porous carbon supported Cu-Fe oxides had good stability and could degrade BPA continuously and stably.Meanwhile,the ion dissolution rate was low,and the catalytic system had a low risk of secondary pollution.In addition,the porous carbon supported Cu-Fe oxide composite catalyst uses cheap plant polyphenol TA as carbon source,has a simple synthesis method and high catalyst yield（41.7%）,which has a good engineering application prospect.This study provides a reliable method for designing highly active metal oxide/carbon composite catalysts to degrade emerging organic pollutants.