State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control On Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
Environ Sci Pollut Res Int. 2022 Oct;29(50):76263-76274. doi: 10.1007/s11356-022-21256-0. Epub 2022 Jun 6.
The all-vanadium redox flow battery (VRFB) is becoming a promising technology for large-scale energy storage due to its advantages such as scalability and flexibility. In recent years, the VRFB has been successfully developed and put into use in many countries. It is expected that the abandoned VRFB will generate a large amount of vanadium waste. To our knowledge, there are few reports on the disposal of spent VRFBs. Herein, chitosan-coated nano-zero-valent iron (CS-Fe) is proposed for the first time as adsorbents for the treatment of spent VRFBs. It can provide a new approach to deal with the upcoming large number of spent VRFBs. The calculated maximum adsorption capacity for V(V) of chitosan and CS-Fe reached 209.5 and 511.3 mg/g at 288 K, respectively. CS-Fe showed better adsorption performance than chitosan under different pH conditions and is easy to be separated from the liquid phase. The Freundlich isotherm was suitable for the adsorption process of chitosan, and CS-Fe was more consistent with the Langmuir isotherm. Ionic strength (0.05-0.5 M) had a positive effect on the adsorption capacity of CS-Fe, and the influence of coexisting anions on CS-Fe could be negligible. FTIR and XPS analyses revealed that the primary mechanisms were the electrostatic attraction of chitosan and redox of Fe. The present study confirmed that CS-Fe could be a potential material to efficiently trap V(V) from the VRFB electrolyte.
全钒氧化还原液流电池（VRFB）由于其可扩展性和灵活性等优势，正成为一种很有前途的大规模储能技术。近年来，VRFB 在许多国家已经成功开发并投入使用。预计废弃的 VRFB 将产生大量的钒废物。据我们所知，关于处理废旧 VRFB 的报道很少。在此，首次提出壳聚糖包覆纳米零价铁（CS-Fe）作为处理废旧 VRFB 的吸附剂。它可以为处理即将大量出现的废旧 VRFB 提供一种新方法。在 288 K 时，壳聚糖和 CS-Fe 对 V(V)的最大吸附容量分别达到 209.5 和 511.3 mg/g。在不同的 pH 条件下，CS-Fe 比壳聚糖具有更好的吸附性能，并且易于从液相中分离。Freundlich 等温线适合壳聚糖的吸附过程，而 CS-Fe 更符合 Langmuir 等温线。离子强度（0.05-0.5 M）对 CS-Fe 的吸附容量有积极影响，共存阴离子对 CS-Fe 的影响可以忽略不计。FTIR 和 XPS 分析表明，主要机制是壳聚糖的静电吸引和 Fe 的氧化还原。本研究证实 CS-Fe 可能是一种从 VRFB 电解质中有效捕获 V(V)的潜在材料。
