Degradation Of Chlorophenol Organic Pollutants Based On Persulfate Advanced Oxidation Processes

Chlorophenol organic pollutants are widely distributed in the ecosystem,even in trace amounts,it will cause serious harm to people’s lives and health.Advanced oxidation technology can produce active free radicals with strong oxidizing properties,such as sulfate radicals（SO₄·^-）and hydroxyl groups（·OH）,for degradation and mineralization of refractory compounds.Heterogeneous catalysts have the advantages of low cost and low energy consumption in the catalytic process,so they are widely used to activate PMS to degrade sewage.However,heterogeneous nanocatalysts have the problems of poor stability.Therefore,developing highly efficient and stable catalysts toward advanced oxidation technology is the key to the activation of peroxymonosulfate（PMS）to degrade organic pollutants.This paper mainly carries out the following work:A simple hydrothermal method was used to synthesize high specific surface area perovskites（LaCoO₃,LaMnO₃）in one step.Using metal-organic framework materials（MOFs）as templates,and calcined at high temperatures to synthesize perovskite nanomaterials.Benefiting from the unusual skeleton structure of MOFs,well-defined architecture and the specific surface area porous perovskite catalysts are much higher than the perovskite catalyst prepared by the combustion method and the sol-gel method,in addition,LaCoO₃ derived from MOFs has a good catalytic effect on the catalytic degradation of 2,4-DCP by activated PMS.This study expands the types of MOFs derivatives and provides a new direction for the application of MOFs derivatives in the field of environment and energy.Nitrogen-doped confined monolithic cobalt-based catalyst（Co-N-CMF）was synthesized by a simple impregnation method using cheap melamine foam as a raw material.The Co-N-CMF catalyst has super high PMS catalytic activity,and the monolithic can be taken out and continued to be used.The 2,4-DCP,ciprofloxacin,bisphenol A,ibuprofen,2,4-dichlorphenoxyacetic acid and other organic pollutants can be removed within 5 min.So it can be seen that the catalyst has universal applicability to the degradation of sewage.The Co-N-CMF/PMS system is an oxidation system based on electron transfer on the surface of the catalyst to active PMS to generate strong oxidizing free radicals to degrade organic pollutants.Besides,the common anions in an aqueous environment(HCO₃^-,CO₃^2-,SO₄^2-,Cl^-,NO₃^-)have no significant effect on the degradation of 2,4-DCP.After five cycles,the Co-N-CMF catalyst can be easily separated,showing long-term stability.In this work,a series of novel monolithic catalysts based on biomass carbon aerogel for PMS activation were prepared by hydrothermal method using waste watermelon peel as raw material.Co-CA catalyst shows high activity for PMS activation with a lower cobalt load and a lower cobalt leaching.Furthermore,it was also found that 2,4-DCP was removed efficiently in different water matrices.Even at0℃,Co-CA catalyst has no significant effect on the degradation rate of 2,4-DCP.Besides,quenching tests and electron paramagnetic resonance（EPR）spectra proved that·OH,¹O₂ and SO₄^·-were generated,while SO₄^·-and ¹O₂ were the major reactive species for 2,4-DCP oxidation.This study provides a cheap,efficient and environmental-friendly monolithic biomass carbon aerogel catalyst for different pollutants degradation,which further advances monolithic catalyst for practical wastewater treatment.Thus,this work not only provides an effective,sustainable,environmentally friendly way for PMS activation,but also broads the application prospects in the field of advanced oxidation technology due to its excellent catalytic performance and low production cost.