Cyanidation is considered the most employed process to recover precious metals such as silver and gold. However, cyanide containing wastes can be hazardous for the environment. Therefore, the soil electroremediation technique was systematically studied to eliminate/degrade the cyanide contained in mining tailing dams using an electrolytic cell with cationic separator and cheap-stable carbon electrodes. The extent and kinetics of cyanide degradation was firstly analyzed in synthetic solutions using the electrolytic cell at different current density, ionic conductivity, and cyanide concentration. The electrolytic system was also evaluated for the treatment of a sample obtained from a mining tailing dam containing cyanide. The results revealed that 100 % of cyanide can be degraded from synthetic solutions containing 200 ppm CN^– at 60 A/m², 0.25 M NaOH and room temperature. It was also found that 100 % of cyanide can be degraded from the real samples obtained from a Mexican mining tailing dam. The kinetic analysis revealed that cyanide degradation can occur through two pathways: a) in the case of tests containing 500 and 800 ppm NaCN, the rate determining step of the cyanide degradation to cyanate species follows a first order reaction with respect to the cyanide ions, and b) when the tests are carried out with 200 ppm NaCN, the same first order reaction controls the process kinetics from 0 to 30 min, while at t > 60 min, the rate determining step for cyanide degradation is modified and limited by the occurrence of parasite reactions. The proposed mechanism for cyanide degradation is also consistent with the thermodynamic calculations. The results also revealed that complete cyanide electro-degradation can be achieved with a current efficiency of 100 %.

氰化被认为是回收贵金属（如银和金）最常用的工艺。然而，含氰化物的废物可能对环境有害。因此，系统地研究了土壤电修复技术，以使用带有阳离子隔膜和廉价稳定碳电极的电解池来消除/降解采矿尾矿坝中的氰化物。首先使用电解池在不同电流密度、离子电导率和氰化物浓度下分析合成溶液中氰化物降解的程度和动力学。还评估了电解系统对从含有氰化物的采矿尾矿坝获得的样品的处理。结果表明，100% 的氰化物可以从含有 200 ppm CN 的合成溶液中降解^–在 60 A/m ², 0.25 M NaOH 和室温。还发现 100% 的氰化物可以从墨西哥采矿尾矿坝获得的真实样品中降解。动力学分析表明，氰化物降解可通过两种途径发生：a) 在含有 500 和 800 ppm NaCN 的试验中，氰化物降解为氰酸盐物质的速率确定步骤遵循与氰化物离子有关的一级反应， b) 当使用 200 ppm NaCN 进行测试时，相同的一级反应将过程动力学控制在 0 到 30 分钟之间，而在 t > 60 分钟时，氰化物降解的速率确定步骤受到修改和限制寄生虫反应。所提出的氰化物降解机制也与热力学计算一致。