Experimental study on electrokinetic removal efficiency of copper-lead contaminated loess enhanced by novel hydrogel electrodes and its inherent mechanism

Taking artificially prepared copper-lead contaminated loess as the research object, a new gel electrode made by the team combined with electrokinetic restoration technology was used to study the migration rule of copper-lead ions in contaminated loess. In the control group of electrokinetic restoration, EKG and a new gel electrode were used in combination with different strengthening methods to analyze the evolution rule of electrokinetic restoration parameters during the experiment. The effect of different strengthening methods on the removal efficiency of heavy metal ions and the internal mechanism were revealed. The results show that: Acid pretreatment combined with the autonomous regulation of the pH of the cathode can significantly reduce the precipitation phenomenon near the cathode and reduce the pH value, resulting in the entire environmental system conducive to the directional migration of cations and ions, thereby increasing the current and temperature, and strengthening the removal efficiency of electrokinetic repair, which further indicates the effectiveness and feasibility of the removal of copper and lead heavy metals by this method. The combination of exchange electrode and point acid can significantly reduce the accumulation of ions near the cathode. Based on the microscopic mechanism of the new gel electrode, the electrode has excellent performance in terms of minimal electrochemical polarization, low resistance and high conductivity. Therefore, a novel gel electrode combined with a new strengthening method is proposed to improve the removal efficiency and solve the problem of "electrochemical polarization and focusing effect of electrode" in electrokinetic process.