Study On The Efficiency Of Three-dimensional Electro-fenton Catalytic Oxidation Of Typical Electronics Industry Wastewater

In the process of electronic industry,a lot of refractory wastewater containing organics and heavy metals is produced,which is difficult to be treated and utilized because of its high concentration of pollutants and poor water quality.Advanced oxidation is currently the most promising technology for the treatment of industrial wastewater.Three-dimensional electric huffington is based on the hydroxyl free radical（·OH）,one of advanced oxidation methods compared with the traditional electric fenton for added particle electrode has higher current efficiency and wider scope advantages,such as p H,has made some achievements in the treatment of refractory wastewater,but in the process of complexing state metal and water generation bromide flame retardants are few research reports.Therefore,this paper is based on Ni-EDTA,Cu-EDTA,and tetraromobisphenol A（TBBPA）,which constructs graphite as a yin,anolymer electrode,and activated carbon particles as a particle electrode,and provides Fe²⁺and magnetic stirring through external.The three-dimensional electric Fantonian system of H₂O₂is generated in the cathode position.In contrast the treatment effect of activated carbon adsorption,electric fenton and three-dimensional electric font,the influencing factors of operational parameters of the three-dimensional electric Fantonian system and coexistence ions were explored,and the degradation of TBPA in three-dimensional electric font system way.The results of the study provide a certain reference for the application of three-dimensional electric Fenton in difficult degradation of electronic industrial wastewater.The same experiment conditions,adsorption,electricity fenton compared with the treatment effect of the three-dimensional fenton method shows that the three dimensional electric fenton high current efficiency,better catalytic oxidation performance,add the activated carbon particles within the system has not only adsorption also increased the electrode surface,improve the effect of the mass transfer,giving play to the role of the particle electrode and make the three dimensional electric fenton the target pollutants removal rate is higher than the sum of activated carbon adsorption and electricity fenton.At room temperature,the effect of Fe²⁺investment,p H,particle electrode investment and current density on three-dimensional electric font removal of pollutants were investigated by single factor.The experimental results show that the optimal operating parameters are as follows:initial p H of water sample is 5,dosage of electrolyte（Na₂SO₄）is 2 g/L,dosage of Fe²⁺is 1 mmol/L,dosage of activated carbon is 4 g/L,and current density is 10 m A/cm².Ni-EDTA,Cu-EDTA reaction 120 min removal rate was 82.28%and 87.26%,respectively;the TBBPA reaction was97.78%,almost completely degraded;mixed water sample reaction 120 min Ni-EDTA,CU-EDTA and TBBPA removal rate were 55.19%,83.29%and 94.97%,respectively.The coexistence of anions and cations in water will affect the treatment effect of three-dimensional electro-Fenton.The experimental results show that Cl^-can generate strong oxidizing Cl O^-and Cu²⁺can generate Fenton-like reaction,which can promote the treatment effect of Ni-EDTA,Cu-EDTA,TBBPA and their mixed waste water to varying degrees.Cl^-has the most significant effect on the degradation of pure TBBPA wastewater,but has less obvious effect on complex heavy metals and mixed simulated wastewater.When Cl^-exists in three-dimensional electro-Fenton system,TBBPA in water is almost completely degraded after 60 min,and the reaction time is 30 min earlier than that in the control group.NO₃^-,HPO₄^2-and Ni²⁺can inhibit the removal of pollutants due to the competitive adsorption relationship,and the inhibition degree is HPO₄^2-﹥NO₃^-﹥Ni²⁺.In order to explore the degradation pathway of TBBPA in three-dimensional electro-Fenton system,gas chromatography-mass spectrometry（GC-MS）was used to determine the following seven intermediate products:1-trimethylsiloxy-3,5-dibromobenzene,2,6-dibromo-4-nitrotoluene,3-bromo-4.5-dimethoxycinnamic acid and 4-tert-butyl.By analyzing the molecular structure of several low bromine products,it is inferred that there are two main ways to degrade TBBPA in three-dimensional electro-Fenton system:C-Br bond breaking and debromination step by step and C-C bond breaking and oxidation.