Preparation Of 3D Nitrogen-Doped Graphene Composite Aerogels And Study On Their Degradation Of The Antibiotics In Water

Tetracycline antibiotics?TCs?are widely used in the treatment of human and animal diseases as a class of broad-spectrum antibiotics.However,due to the poor metabolism of humans and animals,large amount of TCs are excreted into the ecosystem,which seriously threaten the ecological safety of water resources.Thus,it is necessary to develop effective technologies to remove TCs from water and maintain a green ecological environment.Herein,two different graphene composit aerogels?3D CoFe₂O₄/N-rGA and 3D CoMn₂O₄/N-rGA?were prepared by green method to activate peroxymonosulfate?PMS?for degradation tetracycline?TC?and oxytetracycline?OTC?.1.Performance and mechanism of 3D CoFe₂O₄/N-rGA activated PMS to degrade TCIn the first part,we designed a three-dimensional nitrogen-doped graphene oxide aerogel anchored with CoFe₂O₄ nanoparticles composite?3D CoFe₂O₄/N-rGA?via simple hydrothermal method.3D CoFe₂O₄/N-rGA could be used for peroxomonosulfate?PMS?activation to generate Hydroxyl radicals?^·OH?and Sulfate radical(SO₄^·-)for highly efficient degradation of TC.The degradation efficiency of TC was detected to be as high as 85%only within 10 s and the degradation rate could remain above 90%after five cycles under the presence of 3D CoFe₂O₄/N-rGA and PMS.At the same time,the effection of factors such as initial pH,PMS concentration,amount of catalyst and anion on the efficiency of catalytic degradation were explored for determining the optimal reaction conditions.The 3D CoFe₂O₄/N-rGA/PMS system also had a high efficiency degradation on different types of antibiotics simulated wastewater.The degradation mechanism of TC in 3D CoFe₂O₄/N-rGA/PMS system was determined by free radical quenching experiments,electron paramagnetic resonance?EPR?,X-ray photoelectron spectroscopy?XPS?and high resolution liquid chromatograph mass spectrometer?HPLC-MS?.2.Performance,mechanism and technology of 3D CoMn₂O₄/N-rGA activated PMS to degrade OTCIn the second part,we used a simple hydrothermal method to successfully embed CoMn₂O₄ nanoparticles in nitrogen-doped reduced graphene oxide aerogel,and we investigated the effects of the rapid degradation of OTC by 3D CoMn₂O₄/N-rGA/PMS systems under different reaction conditions.A variety of simulated antibiotic wastewater and actual pharmaceutical wastewater have been tested and achieved outstanding results.It was confirmed that the degradation system was dominated by^·OH and SO₄^·-via EPR and free radical quenching experiments.The possible degradation path of OTC in 3D CoMn₂O₄/N-rGA/PMS system was determined by HPLC-MS.A mini fixed bed experimental device was constructed,which achieved excellent results on the tests of high-concentration simulated wastewater and actual pharmaceutical wastewater.In order to further realize the industrial application of advanced sulphate oxidation process?SR-AOPs?,a flow chart of instrument control was designed.It was hoped that it could provide a reference for the industrial application of SR-AOPs process.