基于石墨纸阴极的电活化过硫酸盐高效降解阿特拉津

Efficient degradation of atrazine by electrochemical activation of persulfate based on graphite paper cathode

针对大多数阴极材料的析氢电势比过硫酸盐(persulfate,PS)的活化电势低,产氢反应抑制了PS的活化,利用析氢电势较高的石墨纸(graphite paper,GP)作为阴极,电活化PS降解废水中难降解有机污染物,为石墨材料作为阴极电活化PS提供理论依据。研究采用GP作为阴极,以阿特拉津(atrazine,ATZ)作为模型污染物,探究GP作为阴极材料电活化PS产生自由基的可行性及降解ATZ的机理。结果表明:当电流为-2 mA,PS浓度为1 mmol×L^(-1),ATZ的浓度为2.3μmol×L^(-1)条件下,GP作为阴极可有效活化PS,产生自由基•OH、SO_(4)^(•−)、O_(2)^(•−)和^(1)O_(2)实现ATZ的降解,经过50 min即可将ATZ完全降解。实验证明GP作为阴极可有效活化PS,且活化效率高,为利用石墨材料作为阴极电活化PS降解ATZ提供新思路。

Most cathode materials have lower hydrogen evolution potentials compared with the potential of electrochemical activation of persulfate(PS)reaction,which inhibits the electrochemical activation of PS.In this study,graphite paper(GP)with high hydrogen evolution potential was used as cathode to activate PS for the degradation of persistent organic pollutants in wastewater,and it provided a theoretical basis for graphite material as cathode to activate PS.GP was adopted as the cathode and atrazine(ATZ)as the model pollutant.The feasibility of GP as cathode to generate free radicals by electrochemical activation of PS and the degradation mechanism of ATZ were studied.The results showed that GP as the cathode could effectively activate PS to generate radicals•OH,SO_(4)^(•−),O_(2)^(•−)and ^(1)O_(2) to completely degrade ATZ after 50 min when I=-2 mA,PS concentration was 1 mmol×L^(-1) and ATZ concentration was 2.3μmol×L^(-1).Meanwhile the experiment proves that GP as cathode could activate PS efficiently,which could effectively degrade ATZ and provide a new idea for using graphite material as cathode to electrochemical activate PS.