Degradation Of Dye Wastewater By Electro-Coupled Co/N Co-Doped Nanoporous Carbon(Co/N-NPC_X) Activated Peroxymonosulfate

Rhodamine B（RhB）is a highly water soluble triphenylmethane dye,which is characterized by its complex structure,high stability,carcinogenicity and neurotoxicity.Therefore,it is of great practical significance to study an efficient and economical method to remove RhB from wastewater.Activated peroxymonosulfate（PMS）technology has gradually attracted attention in the treatment of organic pollution due to its strong oxidizing ability.In addition,the introduction of electrochemical oxidation is expected to improve the utilization of catalysts and oxidants.Therefore,electrochemical oxidation and activated PMS technology are combined to achieve high-efficiency removal of pollutants.The main research conclusions of this thesis include the following aspects:（1）Zn/Co-ZIF_X was successfully synthesized by stirring at room temperature,and converted to Co/N-NPC_X by calcination in N₂ atmosphere.By adjusting the molar ratio of Zn to Co and the calcination temperature,the controllable synthesis of Co/N-NPC_X can be achieved.The research results show that with the increase of the molar ratio of Zn to Co,the particle size of Zn/Co-ZIF_X becomes slightly smaller.This phenomenon is more obvious in Co/N-NPC_X.XRD and VSM analysis show that with the increase of calcination temperature,the crystallinity and saturation magnetization of Co/N-NPC_0.5 increases.（2）The prepared Co/N-NPC_0.5 catalyst was applied to the activated PMS system to investigate its effect on RhB removal.The research results show that when the dosage of Co/N-NPC_0.5 was 5 mg/L,the optimal oxidant required for the treatment of 10 mg/L RhB wastewater was 1.25 m M and the optimal p H is 4,and it can reach 100%removal rate.This thesis also explored the effect of initial PMS concentration and initial p H on the removal of RhB from the system.The research results show that the higher the initial PMS concentration,the better the removal effect of RhB.The initial p H has little effect on the removal of RhB,and shows a high removal rate in a wider p H range.In addition,through free radical quenching experiments and EPR detection,the catalytic oxidation mechanism of the Co/N-NPC_0.5/PMS system was explored,and the active species produced in this system were SO₄·^-、·OH and ¹O₂.（3）The quantitative impregnation method was used to successfully load Zn/Co-ZIF_X on GF,and it was converted into Co/N-NPC_X/GF by calcination under N₂ atmosphere to realize the modified preparation of the electrode.The morphologies of GF,Zn/Co-ZIF₁/GF and Co/N-NPC₁/GF was analyzed by SEM.The electrochemical performance of the modified electrode was explored.The research results showed that Co/N-NPC₁/GF has low impedance,better mass transfer ability and catalytic activity.（4）Using the modified Co/N-NPC₁/GF electrode as the cathode,the removal effect of RhB in the electro-activated PMS system was investigated.The research results show that when the condition of natural p H was 5.4,the initial PMS concentration was 1.25 m M,and the current density was 20 m A/cm²,100%of RhB could be removed within 60 minutes.This thesis explored the effects of initial PMS concentration,current density,initial p H,inorganic anions and HA on the removal of RhB from the system.The research results show that with the increase of the initial PMS concentration and current density,the removal rate of RhB presents a trend of first rising and then falling.Acidic conditions are conducive to the removal of RhB,the removal rate of RhB decreases under alkaline condition,but the removal effect is the worst when the acid is too strong.Cl^-promotes the removal of RhB,and HCO₃^-、PO₄^3-and HA inhibit the removal of RhB.In addition,through free radical quenching experiment and EPR detection,the catalytic oxidation mechanism of the system was also explored,and the active species produced in this system were SO₄·^-、·OH and ¹O₂.