Preparation Of Modified Ti/SnO₂-Sb Electrode And Its Ultrasonic Electrochemical Degradation Of Malachite Green Wastewater

In recent years,with the increasing production of dyes,it was not easily to decompose in water,so it was very important to explore the degradation technology of dye wastewater.Relevant studies had shown that the catalytic activity of the electrode can be effectively improved by doping graphene and rare earth elements to the electrode material.Ultrasonic electrochemistry was an advanced oxidation method that combines ultrasonic oxidation and electrochemical oxidation.This method was a relatively new technology.In this paper,graphene and rare earth Gd were introduced into the Ti/Sn O₂-Sb electrode,and it was determined that graphene and rare earth Gd were co-doped,and the electrode with a calcination temperature of600°C had the best performance.In the experiment,various test methods were used to test the morphology,structure and electrochemical activity of the self-made modified electrode.The results showed that the surface coating of the electrode doped with graphene and rare earth Gd was denser and the grain size was significantly smaller.The stability of the electrode was enhanced.Graphene and rare earth Gd were successfully doped into electrode substrates.And through electrochemical tests,it was found that compared with other doped electrodes,the oxygen evolution potential of the electrodes doped with graphene and rare earth Gd increased significantly,and the peak current was the largest.In this study,the optimal reaction parameters for ultrasonic electrochemical degradation of malachite green wastewater with self-made modified electrodes were determined as follows:reaction time60 min,voltage 10 V,ultrasonic power 240 W,initial solution concentration 40 mg L^-1,malachite green here The degradation rate under conditions was 97.3%.The degradation kinetics and activation energy of three degradation systems for malachite green were studied,and it was found that the concentration of malachite green solution hardly changed during ultrasonic degradation alone,and the degradation of malachite green in separate electrolysis and ultrasonic electrochemical systems followed the first order.The kinetic law of the reaction,and the introduction of ultrasound makes the reaction activation energy of the electrochemical system significantly reduced.Under the ultrasonic electrochemical technology,the degradation efficiency of malachite green reaches the highest.In addition,sonoelectrochemical technology activates the electrode surface and avoids passivation.Simultaneously,the degradation process of malachite green by ultrasonic electrochemistry was investigated by means of liquid phase mass spectrometry.It was found that the p H of the solution increased continuously with the progress of the degradation reaction.And malachite green was oxidized by sonoelectrochemically generated·OH,resulting in N-demethylation of the malachite green molecule and cleavage of the central carbon structure.