Deep treatment, a method for further reducing the content of a target substance, for toxic arsenic (As) from water is vital to reduce environmental pollution and ensure human health. Here, we employed electrosorption of As(V) from water in a self-made three-dimensional reactor with granular activated carbon (GAC). The As(V) concentration can be decreased from 0.5 to 0.032 mg/L under optimal conditions, and all of the As practically presented as H₂AsO₄⁻ without As(III), indicating that there was no redox reaction. After kinetic studies and comparisons of pseudo-second-order kinetic, intra-particle diffusion and Boyd models, the electrosorption could be divided into three steps: internal diffusion from the surface of materials to internal pores, liquid film diffusion from the solution to the surface of materials, and the closure of the entire adsorption process to the equilibrium state. In order to verify the cyclic performance of this process, electrosorption-electrodesorption process research was carried out, and it was found that after 8 cycles, the concentration in the effluent was still only 0.098 mg/L, which was lower than the limitation. Above all, both removal efficiency and disposal of adsorption materials should be ameliorated even though As(V) could be removed in depth and recycled.

深度处理是一种进一步降低水中有毒砷（As）目标物质含量的方法，对于减少环境污染、保障人类健康至关重要。在这里，我们在自制的带有颗粒活性炭（GAC）的三维反应器中从水中电吸附As（V）。在最佳条件下，As(V)浓度可以从0.5 mg/L降低到0.032 mg/L，并且所有As实际上都以H ₂ AsO ₄ ^-形式存在，没有As(III)，表明没有发生氧化还原反应。经过动力学研究以及准二级动力学、颗粒内扩散和Boyd模型的比较，电吸附可分为三个步骤：从材料表面到内部孔隙的内部扩散、从溶液到表面的液膜扩散材料的吸附，使整个吸附过程闭合至平衡状态。为了验证该工艺的循环性能，开展了电吸附-电解吸工艺研究，发现经过8次循环后，出水中浓度仍仅为0.098 mg/L，低于限值。最重要的是，尽管As(V)可以深度去除并回收利用，但去除效率和吸附材料的处理都需要改善。