División Polímeros Nanoestructurados, INTEMA-CONICET, Facultad de Ingeniería, UNMdP, Av. Juan B. Justo, 4302, B7608FDQ, Mar del Plata, Argentina.
División Catalizadores y Superficies, INTEMA-CONICET, Departamento de Ingeniería Química, Facultad de Ingeniería, UNMdP, Av. Juan B. Justo, 4302, B7608FDQ, Mar del Plata, Argentina.
J Environ Manage. 2020 Jun 1;263:110403. doi: 10.1016/j.jenvman.2020.110403. Epub 2020 Mar 17.
In this study, we prepared TiO porous electrodes with continuous layered structures characterized by different layer-to-layer distance (from 2 to 10 μm) but the same total void fraction (88-90%), to modulate the electrodes' permeability and the volumetric electrochemical surface area (from 90 to 840 cm cm). These platforms were evaluated as anodes in the electro-oxidation (EO) of bentazon in a three-electrode cell under galvanostatic conditions, operated both in traditional batch (TB) or batch recycle flow-through (BRFT) modes. The performance was significantly enhanced when the liquid was recirculated through the lamellar structure of the electrodes. In BRFT mode, the electrode interlayer gap was found to be a key factor to control the bentazon and total organic carbon (TOC) conversions. For the best conditions evaluated (BRFT, 10 μm-interlayered TiO electrodes with a volumetric surface area of 90 cm cm), the effect of the applied current (1 or 3 mA) and liquid flow rate (10, 12 or 14 mL. min) was investigated. Specific energy consumption (SEC) values were estimated to reveal the performance of each of the EO treatments from an energetic point of view. The use of 10 μm-interlayered TiO electrodes at 1 mA in BRFT mode at a flow rate of 14 mL min showed the best results, yielding 85% bentazon removal, 57% mineralization and SEC values of 0.006 kWh.g after 6 h of treatment. This contribution highlights the use of layered TiO electrodes as a promising strategy for intensifying EO processes, pointing to a trade-off between the accessibility to the internal electrode structure and the volumetric electrode surface area to enhance the contact between the target molecules and the hydroxyl radicals physisorbed on the electrode surface, while minimizing simultaneously the energy requirements.
在这项研究中，我们制备了具有不同层间距（2-10μm）但具有相同总空隙率（88-90%）的连续层状结构的 TiO 多孔电极，以调节电极的渗透性和体积电化学表面积（90-840cmcm）。这些平台被评估为在恒电流条件下在三电极电池中作为电氧化（EO） Bentazon 的阳极，分别在传统批量（TB）或批量循环流动（BRFT）模式下运行。当液体在电极的层状结构中循环时，性能得到显著提高。在 BRFT 模式下，发现电极层间间隙是控制 Bentazon 和总有机碳（TOC）转化率的关键因素。在所评估的最佳条件下（BRFT，10μm 层间 TiO 电极，体积表面积为 90cmcm），研究了施加电流（1 或 3mA）和液体流速（10、12 或 14mL.min）的影响。从能量角度估计比能量消耗（SEC）值以揭示每种 EO 处理的性能。在 BRFT 模式下以 1mA 使用 10μm 层间 TiO 电极，流速为 14mLmin 时，效果最佳，在 6 小时的处理后，Bentazon 的去除率为 85%，矿化率为 57%，SEC 值为 0.006kWh.g。本研究强调了使用层状 TiO 电极作为强化 EO 过程的有前途的策略，指出了内部电极结构的可及性和体积电极表面积之间的权衡，以增强目标分子与电极表面物理吸附的羟基自由基之间的接触，同时最小化能量需求。
