Modification Of Graphene Aerogel Particle Electrodes And Study On Treatment Of Wastewater Containing Bisphenol A

At present,Endocrine Disruptors Compounds?EDCs?have been widely used in various aspects of society,such as industrial by-products,plastics,pharmaceuticals,health products and pesticides.Long term exposure to EDCs can cause normal hormonal function and physiological condition of animal and human changes,which constitute huge menace to the survival of human and animal and the reproduction of the species.Its harm has caused widespread concern all over the world.The research about the treatment of EDCs began to enter people's vision,accordingly.The traditional adsorption and biodegradation technology has the disadvantages such as the degradation is not thorough,easy to result in secondary pollution.Compared with the traditional processing technology,electrochemical treatment techniques generally do not need to add too many chemicals,but also because of it is simple,and take up space is small,also easy to manage,then the amount of sludge near zero emissions,which many researchers called it clean water treatment technology.In recent years,the electrochemical method has been extensively used in water treatment.Among them,because of its characteristics of environmental conservation,high efficiency and simple operation,the three-dimensional electrode method has been widely used in the treatment of heavy metals and refractory pollutants in the water.Moreover,the research of three-dimensional electrode method remove of organic pollutants is also increasing.This paper chooses the typical EDCs-Bisphenol A?BPA?as the target pollutant.The treatment of effluent containing BPA was investigated experimentally using nitrogen-doped graphene aerogels?NGAs?as particle electrodes in a three-dimensional electrode reactor for the electrochemical treatment was studied.Furthermore,the experimental result compares with the traditional activated carbon working electrodes.The effects of factors such as cell voltage,electrolyte dosage,the ratio of NGAs mass to solution volume and pH value on the degradation of BPA were investigated.The results showed that the removal rates of BPA and COD were 91.4% and 82.3% under the optimal reaction conditions.In order to research the durability of the electrode,the repeated degradation experiments were designed.After 50 times of repeated,the removal efficiency of BPA and COD were 85% and 73%,respectively.The intermediate products of electrochemical oxidation of BPA were identified by liquid chromatography-mass spectrometry liquid chromatography?LC-MS?,then a probable BPA degradation pathwaywas proposed.It was considered that ·OH radicals by water electrolysis could constantly attack the aromatic ring to form various intermediates such as hydroxylated-BPA,isopropylphenol,hydroquinone,phenol and butantetraol,maleic acid,oxalic acid.These compounds were eventually mineralized by electrolysis into CO₂ and H₂O.