State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200098, China.
Department of Chemical Engineering, University of Engineering and Technology, Lahore, Pakistan.
Sci Total Environ. 2019 Feb 15;651(Pt 1):1182-1188. doi: 10.1016/j.scitotenv.2018.09.148. Epub 2018 Sep 13.
The surface properties of nanocomposites are influenced by the existence of inorganic species that may affect its performance for specific catalytic applications. The impact of different ionic species on particular catalytic activity had not been investigated to date. In this study, the surface charge (zeta potential) of graphene-oxide-supported nano zero valent iron (G-nZVI) was tested in definitive cationic (Na, K, Ca and Mg) and anionic (Br, Cl, NO, SO, and HCO) environments. The efficiency of G-nZVI catalyst was inspected by measuring the generation of reactive oxygen species (ROS) for the degradation of 1,1,1-trichloroethane (TCA) in sodium percarbonate (SPC) system. Tests conducted using probe compounds confirmed the generation of OH and O radicals in the system. In addition, the experiments performed using scavenging agents certified that O were primary radicals responsible for TCA removal, along with prominent contribution from OH radicals. The study confirmed that G-nZVI catalytic capability for TCA degradation is notably affected by various cationic species. The presence of Ni and Cu significantly enhanced (94%), whereas Na and K had minor effects on TCA removal. Overall, the results indicated that groundwater ionic composition may have low impact on the effectiveness of G-nZVI-catalyzed peroxide TCA treatment.
纳米复合材料的表面性质受无机物种的存在影响，这些无机物种可能会影响其在特定催化应用中的性能。迄今为止，尚未研究不同离子物种对特定催化活性的影响。在这项研究中，测试了氧化石墨烯负载的纳米零价铁（G-nZVI）在明确的阳离子（Na、K、Ca 和 Mg）和阴离子（Br、Cl、NO、SO 和 HCO）环境中的表面电荷（zeta 电位）。通过测量在过碳酸钠（SPC）系统中 1,1,1-三氯乙烷（TCA）的降解生成的活性氧物质（ROS）来检查 G-nZVI 催化剂的效率。使用探针化合物进行的测试证实了系统中 OH 和 O 自由基的生成。此外，使用清除剂进行的实验证明，O 是主要负责 TCA 去除的自由基，同时 OH 自由基也有显著贡献。该研究证实，G-nZVI 对 TCA 降解的催化能力受到各种阳离子的显著影响。Ni 和 Cu 的存在显著增强了（94%），而 Na 和 K 对 TCA 的去除影响较小。总体而言，结果表明地下水的离子组成可能对 G-nZVI 催化过氧化物 TCA 处理的有效性影响不大。
