多孔活性金属氧化物涂层阳极电化学催化氧化刚果红的性能与机制OA

Addressing the challenges of high salinity,recalcitrant degradation in dyeing wastewater,and the limitations of conventional anodes including restricted mass transfer and easy shedding of coating,a RuO2@r-TiO2 NTAs electrocatalytic anode membrane was fabricated via a three-step process involving anodic oxidation,electrochemical reduction,and thermal decomposition.This anode was integrated with a graphite felt(graphite felt,GF)cathode to construct a flow-through electrochemical oxidation reaction system.The morphology and physicochemical properties of the materials were characterized by SEM,XRD and XPS.Using Congo Red(Congo red,CR)as the target pollutant,the electrocatalytic degradation performance of the system was investigated under flow-through mode.The effects of current density,permeability,pollutant concentration,and chloride concentration on CR removal efficiency were examined.The results demonstrated that under optimal operating conditions(current density:5 mA·cm-2,permeability:480 L·m-2·h-1,initial CR concentration:0.15 mmol·L-1,NaCl concentration:75 mmol·L-1),the system achieved a 91%decolorization efficiency for CR within 20 minutes and an 82%mineralization efficiency after 60 minutes.Mass transfer performance tests confirmed that the flow-through mode exhibited a mass transfer rate constant(2.23×10-4 m·s-1)in the circulation mode three times higher than that of the conventional mode.The production of active chlorine(0.61 mmol·L-1)and H2O2(0.24 mmol·L-1)increased by 32.8%and 66.7%,respectively.Radical quenching experiments identified singlet oxygen(1O2)as the primary active substances responsible for the degradation process.Based on the results of radical quenching experiments and UV-Vis spectral analysis,a degradation mechanism for CR within this system was proposed.The system achieved>90%decolorization rate for five types of typical dye pollutants,including CR,with a remarkably low unit energy consumption of only 0.16 kWh·m-3.Cyclic voltammetry curves of the electrode confirmed its long-term stability of the system.The obove research results can provide a valuable theoretical reference for the application of electrochemical advanced oxidation processes(electrochemical advanced oxidation processes,EAOPs)in the treatment of high-salinity dyeing wastewater.