Degradation Of Azo Dyes In Aqueous Solution By High Voltage Discharge Plasma/carbon Based Fe/Cu Bimetals And High Voltage Discharge Plasma/persulfate

Compared with traditional methods,high-voltage discharge plasma has obvious advantages such as simpler operation,higher efficiency and wider application scope.There are a large number of different kinds of active particles in the high voltage discharge plasma,which are more active and more active than ordinary chemical reactions,and more likely to react with the organic matter in contact.In this paper,the ractive red(RR120)was selected as the target contaminant,respectively we studied the degradation of RR120 in the water by high voltage discharge plasmas with the Fe/Cu bimetal,as well as the degradation of RR120 in the water by high voltage discharge plasma with persulfate,and analyzed the main factors affecting the degradation of RR120.The synergetic degradation mechanism of RR120 was discussed.At the same time,the response surface model of RR120 was established.Finally,the influence of multiple factors on the degradation efficiency of RR120 was simulatedFirstly,the carbon based Fe/Cu bimetal catalyst was synthesized by hydrothermal method,which was characterized by X-ray diffraction,Brunauer-Emmett-Teller surface area and scanning electron microscopes,and the degradation mechanism of RR120 in aqueous solution by high voltage discharge plasma and carbon based Fe/Cu bimetal was studied.This paper mainly studied the influence of air flow,initial concentration,the amount of catalyst and discharge power on the removal efficiency of RR120,as well as the degradation intermediates of RR120 by GC-MS.The pseudo first-order reaction kinetics could be used to describe the degradation process of RR120.When the air flow was 60L/h,the power was 40 W,the initial concentration was 50 mg/L,and the amount of catalyst was 30 mg,the removal efficiency of RR120 reached the maximum.Compared with the single high-voltage discharge plasma system,the RR120 removal efficiency increased by 40.6% at the condition of high voltage discharge plasma with Fe/Cu bimetal.At the same time,the influence of air flow,discharge power,initial concentration and the addition of catalyst on the degradation efficiency of RR120 were also investigated.In the process of RR120 degradation by the high-voltage discharge plasma with the Fe/Cu,the pH of RR120 aqueous solution decreased from 4.58 to 2.26,and the conductivity increased from 66.7 to 574.7 ?S/cm.The degradation products of RR120 were determined by GC-MS,and the degradation pathway of RR120 was deduced according to the detected degradation intermediates,which mainly resulted in open-loop reaction,conjugate structure destruction,dechlorination and hydroxylation.Secondly,the degradation of RR120 in water by high voltage discharge plasma and persulfate was studied.Compared with the single high-voltage discharge plasma system and the single persulfate system,the degradation efficiency of RR120 caused by the high voltage discharge plasma with persulfate increased by 21.5% and 98.0% respectively.The effects of initial pH,discharge power,initial concentration and the addition of persulfate on the degradation efficiency of RR120 were also discussed.The results showed that the discharge power of 65 W,acidic conditions,and the addition of persulfate were 4 mmol/L are the best conditions.The pseudo first order reaction kinetics was followed in the degradation of RR120 by high-voltage discharge plasma and the persulfate.In the synergetic process of RR120 degradation,the pH value of RR120 aqueous solution decreased and the conductivity increased steadily.The determination of RR120 degradation intermediates was based on GC-MS,and the possible degradation pathway of RR120 was proposed;open-loop reaction,conjugate structure destruction,dechlorination and hydroxylation were the main reactions.Lastly,that response surface method model of RR120 was respectively established for the high voltage discharge plasma with the carbon based Fe/Cu bimetal and the high-voltage discharge plasma with persulfate.With the experimental data as samples,the best experimental conditions for the synergistic degradation of RR120 were obtained by the training and test of the response surface method model for the two synergistic systems.