Removal Of Sulfamethoxazole By Activating Sodium Persulfate With Fe₃O₄@PAC

Antibiotic is a kind of medicine that can inhibit or affect the function of microorganisms.It plays a recurring role not only in animal husbandry and aquaculture but also in the treatment and prevention of human diseases.Due to the mass production and use of antibiotics,there is little prospect of releasing antibiotic wastewater.Antibiotics are highly resistant to conventional wastewater treatment plants,so they will be continuously excreted in the natural environment（especially the aquatic environment）.Antibiotics have been reported in many waters around the world,with the maximum concentration reaching mg L^-1.Antibiotics that invade the environment will not only affect the activities and population structure of microorganisms,but also produce bacterial drug resistance and drug resistance genes,posing a major threat to human health and the ecosystem.Therefore,seeking effective,economical and environmentally friendly antibiotic wastewater treatment technology is a major problem at home and abroad.Basically,peroxymonosulfur（PS）activated advanced oxidation technology is shown.Highly resistant pollutants（antibiotics）have huge potential.Completely polluted dyed products,methods can be used for the precursors and biodegraded products,which are environmentally harmful.Persulfate activation,high-grade oxidization,technical research,major concentration,activation of various types,activation,catalyst-like development,focus on shadow processing efficiency factors,and each factor presence,actual application,medium shadow measurement,and small manned measurement.Research on the above-mentioned problems,activated carbon used by the author,Fe₃O₄,catalysts,activation,persulfate,persulfate,and water.Shadow factor/catalytic performance Degree of total elimination effect This research is highly resistant to pollutants（antibiotics）.Main discussion below:（1）Fe₃O₄@PAC composites with activated carbon as carrier and Fe₃O₄as catalyst were prepared by hydrothermal synthesis.SEM analysis shows that the surface of activated carbon is loose and porous,with more Fe₃O₄nanoparticles attached uniformly,and the loading effect is good.XRD analysis shows that Fe₃O₄crystal exists in Fe₃O₄@PAC material.The XRD patterns of Fe₃O₄nanoparticles and Fe₃O₄@PAC materials were calculated and compared by Scheler formula,and it was found that Fe₃O₄nanocrystals loaded on the surface of activated carbon were smaller:d（after loading）=0.618 nm;D（before loading）=0.957 nm,which makes Fe₃O₄@PAC have more stable catalytic efficiency.The EDS and XPS analysis show that the main elements in Fe₃O₄@PAC composites are Fe,o and C.The FT-IR spectra and XPS spectra show that there are C-C bond,C-H bond and Fe-O bond on the surface of the material.The Fe element exists in the form of coexistence of Fe²⁺and Fe³⁺,which accords with the chemical properties of Fe₃O₄.O mainly exists in the form of iron oxide and physical adsorption.（2）The decomposition efficiency of SMX in the above is stronger than the decomposition efficiency in an alkaline environment,and the removal efficiency decreases as the p H rises in the p H range（3～11）.After 255 minutes,the removal efficiency of SMX drops from 99.02%to 90.72%.Periodic experiments show that Fe₃O₄@PAC has excellent catalytic stability and can be reused.Compared to the last cycle experiment,the SMX removal rate in the first cycle experiment was reduced by only 16.36%.We compared the removal efficiency of common anions（NO₃^-,HCO₃^-,Cl^-）and humic acid（HA）that coexist with SMX.NO₃^-,HCO₃^-,Cl^-,and HA have been shown to interfere with the removal of SMX by the Fe₃O₄@PAC/PS system.The inhibitory intensity did not clearly increase with increasing NO₃^-concentration.After 270 minutes,the SMX removal rate decreased from 99.02%to 90.72%.HCO₃^-can significantly reduce SMX degradation in Fe₃O₄@PAC/PS systems.With increasing HCO₃-concentration,the SMX removal rate decreased from 96.14%to 73.49%after the 270 minute reaction.Cl^-has no apparent inhibitory effect on SMX removal in the Fe₃O₄@PAC/PS system,with SMX removal rates decreasing from 96.14%to 89.13%after 270 minutes.With the addition of HA,the efficiency of SMX removal by the Fe₃O₄@PAC/PS system has also dropped from 94.14%to 85.79%.Fe₃O₄@PAC/PS may accelerate the removal of SMX in the presence of heavy metal pollutants（Zn,Cu,Ni）in the water.It was found that the removal rate of SMX increased with increasing metal concentration by adding different concentrations of heavy metals.（3）The main free radicals involved in SMX removal in Fe₃O₄@PAC/PS system are.SO₄^-and.OH^-,and the leading free radical is.SO₄^-.14 metabolites produced during SMX degradation were predicted by SPE-LC-MS,and 5 possible metabolic pathways during SMX degradation were predicted.