State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China.
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China.
Chemosphere. 2020 Feb;241:125125. doi: 10.1016/j.chemosphere.2019.125125. Epub 2019 Oct 17.
Acid Orange 7 (AO7), as a most common and widely used synthetic dyes in the printing and dyeing industry, was hardly degradable by traditional wastewater treatment methods. Here, activated carbon fiber (ACF) as an in-situ regenerated cathodic adsorbent in the electrochemical/Fe/peroxymonosulfate process (EC/ACF/Fe/PMS) was firstly investigated for AO7 removal and compared with several different processes. The results indicated that the effective adsorption of AO7 on ACF can be enhanced under electrolytic conditions, while the adsorbed AO7 on ACF can be completely degraded and mineralized in EC/ACF/Fe/PMS process resulting in the in-situ regeneration of ACF. Besides, the electrical energy per order values were investigated, which showed an apparent reduction of electrical energy consumption from 0.42831 to 0.09779 kWh m when ACF-cathode replaced Pt-cathode. Further study revealed that higher conversion rate of Fe from Fe was observed with ACF-cathode. It deserved to be mentioned that the removal efficiency of AO7 was satisfactory and stable even after reusing ACF cathode for 10 times. Furthermore, structure and elements of ACF surface were investigated, which indicated the structure of ACF was intact in EC/ACF/Fe/PMS due to inhibition of ACF corrosion by electron migration at cathode. In addition, the total iron content of the effluent in EC/ACF/Fe/PMS was lower than that of EC/Fe/PMS due to the deposition of iron on ACF-cathode surface. Therefore, advantages of EC/ACF/Fe/PMS for AO7 degradation were not only a much higher oxidation efficiency and in-situ regenerated cathodic adsorbent, but also a lower electrical energy consumption and lesser iron ions contents in the effluent.
酸性橙 7（AO7）作为印染行业最常用、最广泛使用的合成染料之一，传统的废水处理方法很难降解。本文首次研究了活性炭纤维（ACF）作为电化学/Fe/过一硫酸盐（EC/ACF/Fe/PMS）过程中的原位再生阴极吸附剂，用于去除 AO7，并与几种不同的工艺进行了比较。结果表明，在电解条件下，ACF 对 AO7 的有效吸附可以增强，而在 EC/ACF/Fe/PMS 过程中，吸附在 ACF 上的 AO7 可以完全降解和矿化，从而实现 ACF 的原位再生。此外，还研究了单位电耗值，结果表明，当用 ACF 阴极代替 Pt 阴极时，电能消耗明显降低，从 0.42831 降至 0.09779 kWh m。进一步的研究表明，ACF 阴极上观察到 Fe 的转化率更高。值得一提的是，即使重复使用 ACF 阴极 10 次，AO7 的去除效率仍然令人满意且稳定。此外，还研究了 ACF 表面的结构和元素，结果表明，由于电子在阴极迁移抑制了 ACF 的腐蚀，因此在 EC/ACF/Fe/PMS 中 ACF 的结构保持完整。此外，由于铁在 ACF 阴极表面的沉积，EC/ACF/Fe/PMS 中流出物的总铁含量低于 EC/Fe/PMS。因此，EC/ACF/Fe/PMS 用于 AO7 降解的优势不仅在于更高的氧化效率和原位再生的阴极吸附剂，而且在于更低的电能消耗和流出物中的铁离子含量。
