Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei, 230009, China; State Key Laboratory of Pollution Control & Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China; Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei, 230024, China.
Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei, 230009, China; East China Engineering Science and Technology Co., Ltd., Hefei, 230024, China.
Chemosphere. 2021 May;271:129575. doi: 10.1016/j.chemosphere.2021.129575. Epub 2021 Jan 9.
Non-thermal plasma (NTP) combined with zinc ferrite-reduced graphene oxide (ZnFeO-rGO) nanocomposites were used for the degradation of aqueous methylparaben (MeP). ZnFeO-rGO nanocomposites were prepared using the hydrothermal method, with the structure and photoelectric properties of nanocomposites then characterized. The effects of discharge power, initial MeP concentration, initial pH, and air flow rate on MeP degradation efficiency were investigated, and the multi-catalytic mechanism and MeP degradation pathways were established. Results showed that ZnFeO-rGO nanocomposites with a 10%:90% mass ratio of GO:ZnFeO had an optimal catalytic effect. The MeP degradation efficiency of NTP combined with ZnFeO-rGO (10 wt%), was approximately 25% higher than that of NTP alone. Conditions favorable for MeP degradation included higher discharge power, lower MeP concentration, neutral pH value, and higher air flow rate. The degradation of MeP by NTP combined with ZnFeO-rGO nanocomposites followed pseudo-first-order kinetics. O, •OH, HO and O were found to play important roles in the MeP degradation, as part of the multi-catalytic mechanism of NTP combined with ZnFeO-rGO nanocomposites. MeP degradation pathways were proposed based on the degradation intermediates detected by gas chromatography mass spectrometry, including demethylation, hydroxylation, carboxylation, ring-opening, and mineralization reactions. The prepared ZnFeO-rGO nanocomposites provide an approach for improved contaminant degradation efficiency, with reduced energy consumption in the NTP process.
非热等离子体（NTP）与锌铁氧体还原氧化石墨烯（ZnFeO-rGO）纳米复合材料联合用于降解水相甲基对羟基苯甲酸酯（MeP）。采用水热法制备了 ZnFeO-rGO 纳米复合材料，并对纳米复合材料的结构和光电性能进行了表征。考察了放电功率、初始 MeP 浓度、初始 pH 值和空气流量对 MeP 降解效率的影响，建立了多催化机制和 MeP 降解途径。结果表明，GO:ZnFeO 质量比为 10%:90%的 ZnFeO-rGO 纳米复合材料具有最佳的催化效果。NTP 与 ZnFeO-rGO（10 wt%）联合处理时，MeP 的降解效率比单独 NTP 提高了约 25%。有利于 MeP 降解的条件包括较高的放电功率、较低的 MeP 浓度、中性 pH 值和较高的空气流量。NTP 与 ZnFeO-rGO 纳米复合材料联合处理时，MeP 的降解遵循准一级动力学。在 NTP 联合 ZnFeO-rGO 纳米复合材料的多催化机制中，O、•OH、HO 和 O 被发现对 MeP 的降解起着重要作用。根据气相色谱质谱检测到的降解中间产物，提出了 MeP 的降解途径，包括脱甲基、羟化、羧化、开环和矿化反应。所制备的 ZnFeO-rGO 纳米复合材料为提高污染物降解效率提供了一种方法，同时降低了 NTP 过程中的能耗。
