Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission, Hubei Province, College of Resource and Environmental Science, South-Central Minzu University, Wuhan, 430074, PR China.
Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission, Hubei Province, College of Resource and Environmental Science, South-Central Minzu University, Wuhan, 430074, PR China.
Chemosphere. 2023 Jul;330:138645. doi: 10.1016/j.chemosphere.2023.138645. Epub 2023 Apr 10.
In a conventional electro-Fenton system with a single cathode, it is difficult to attain both high HO generation by oxygen reduction reaction (ORR) and efficient iron reduction reaction (FRR). For this study, a flow-through dual-system electro-Fenton (FT-DEF) reactor was designed to overcome this shortcoming and promote mass transfer to effectively remove dimethyl phthalate (DMP) from water. By comparing the ORR and FRR performances of four different commercial carbon electrodes, the graphite felt with the highest amount of HO generation was selected as the cathode of the ORR system, and the activated carbon fiber with the best Fe (III) reduction effect was selected as another cathode of the FRR system. The ORR system and FRR system operate simultaneously to form the DEF system. The FT-DEF system displayed many advantages compared with the conventional electro-Fenton (CI-ORR), presenting an improved efficiency and low energy consumption in phthalates removal. Under optimal reaction conditions, the FT-DEF system is capable to degrade 100% DMP in 20 min, which is 25% higher than the CI-ORR, while the reaction rate constant (0.271 min) is 16 times that of CI-ORR system (0.017min). In addition, the TOC removal of FT-DEF achieving 72.3% within 2 h with energy consumption of 2.35 kW h·m is much better than CI-ORR that only achieves 18.3% TOC removal within 2 h with energy consumption of 8.13 kW h·m. Furthermore, control parameters and mechanism of FT-DEF were investigated in detail. The main intermediate products of DMP were analyzed by UPLC-ESI-HRMS, and the possible degradation path of DMP was speculated. In addition, application of FT-DEF in three types of natural water demonstrated its universal applicability of the system.
在具有单个阴极的传统电芬顿系统中，很难同时实现高的 HO 通过氧还原反应（ORR）生成和有效的铁还原反应（FRR）。为了解决这个问题，本研究设计了一种流通式双体系电芬顿（FT-DEF）反应器，以克服这一缺点并促进传质，从而有效地从水中去除邻苯二甲酸二甲酯（DMP）。通过比较四种不同商业碳电极的 ORR 和 FRR 性能，选择产生 HO 生成量最高的石墨毡作为 ORR 系统的阴极，选择 Fe（III）还原效果最佳的活性碳纤维作为 FRR 系统的另一阴极。ORR 系统和 FRR 系统同时运行，形成 DEF 系统。与传统电芬顿（CI-ORR）相比，FT-DEF 系统具有许多优势，在去除邻苯二甲酸酯方面表现出更高的效率和更低的能耗。在最佳反应条件下，FT-DEF 系统能够在 20 分钟内降解 100%DMP，比 CI-ORR 提高了 25%，而反应速率常数（0.271min）是 CI-ORR 系统的 16 倍（0.017min）。此外，FT-DEF 的 TOC 去除率在 2 小时内达到 72.3%，能耗为 2.35kW·h·m，优于 CI-ORR 在 2 小时内仅达到 18.3%的 TOC 去除率和 8.13kW·h·m 的能耗。此外，还详细研究了 FT-DEF 的控制参数和机制。通过 UPLC-ESI-HRMS 分析了 DMP 的主要中间产物，并推测了 DMP 的可能降解途径。此外，FT-DEF 在三种类型天然水中的应用证明了该系统的通用性。
