-
近年来,由水中抗生素超标导致的水体污染、生态毒害以及诱生超级耐药性基因(ARGs)等问题引起了广泛关注[1],有针对性的治理技术亟待开发. 在报道的水处理技术中,基于过硫酸盐活化的高级氧化技术(SR-AOPs)由于具有绿色环保、氧化效率高以及使用范围广等优点而被广泛应用于水中有机污染物的去除[2],其中高效且稳定的催化剂是该技术的关键所在.
金属有机框架(MOFs)是由金属离子中心和有机配体通过自组装形成的三维周期网格结构[3-4],具有比表面积大、结构性质可调和活性位点丰富等特点,有望在过硫酸盐活化体系中展现出优异的性能[5-6]. 例如,ZIF-8是由锌离子与2-甲基咪唑配位键形成的新型多孔材料,相比于其他MOFs材料具有良好的水热稳定性和化学稳定性[7-8]. 镍和锌位于元素周期表同一周期中,核外电子排列具有高度的结构相似性. 研究表明,将镍掺杂到ZIF-8中会影响sp2 C位点的电子结构、产生活化位点,从而改变催化活性[9].
粉末状MOFs还存在易团聚和难回收等问题[10]. 为此,有学者提出将电化学和膜过滤构筑在一个操作单元内形成电催化膜系统[11],以期产生一定的协同作用. 例如,Zheng等[12]提出利用比表面积大、导电性好的碳纳米管(CNT)作为载体对纳米材料进行妥善搭载的解决方案. CNT作为载体可以避免纳米催化剂的团聚,CNT、纳米催化剂和辅助电场之间发挥了显著的协同作用;然而,构筑金属有机骨架(MOFs)基的电催化膜材料用于活化过硫酸盐和降解有机微污染物的相关研究却鲜有报道.
本实验以CNT为载体,设计制备了CNT/Ni-ZIF-8纳米复合电催化膜,开展了活化过硫酸盐降解磺胺甲噁唑(sulfamethoxazole, SMX)的性能和机理研究,探究了制备条件与纳米复合膜理化性质间的构效关系,分析并优化了镍的掺杂量,考察了降解实验参数(如电压、流速和PMS用量等)对SMX降解动力学的影响,研究了CNT、MOFs催化剂和电场之间的相互作用,进一步通过自由基淬灭实验和EPR测试来明确反应体系中主要的活性物种,阐明了催化降解的内在工作机制.
金属有机框架(MOFs)基电催化膜活化过硫酸盐降解磺胺甲噁唑
Degradation of sulfamethoxazole by metal-organic framework (MOFs)-based electrocatalytic membrane activated by peroxymonosulfate
-
摘要: 基于过硫酸盐(peroxymonosulfate,PMS)活化的高级氧化技术在降解新污染物方面具有独特优势. 本实验利用碳纳米管(carbon nanotubes,CNT)搭载Ni-ZIF-8,设计制备了CNT/Ni-ZIF-8纳米复合电催化膜,开展了活化过硫酸盐降解磺胺甲噁唑(sulfamethoxazole,SMX)的性能和机理研究. 探究了制备条件与纳米复合膜理化性质间的构效关系,分析并优化了镍的掺杂量,考察了降解实验参数(如电压、流速和PMS用量等)对SMX降解动力学的影响. 研究表明,Ni-ZIF-8均匀地负载在碳纳米管表面. 在最佳条件时(镍掺杂量为20%、电压为−1.5 V、流速为1.5 mL·min−1和PMS用量为1.5 mmol·L−1),单次流模式下去除5 mg·L−1 SMX的效率为76.6%. 电子顺磁共振谱和淬灭实验结果表明,·OH和1O2均参与到SMX的降解过程中. 本研究为开发高效电催化膜催化材料提供了新的设计思路.Abstract: Peroxymonosulfate (PMS) activation-based advanced oxidation technology has attracted wide attention toward the decontamination of emerging contaminants. In this study, carbon nanotubes (CNT) were used to host Ni-ZIF-8 to construct CNT/Ni-ZIF-8 electrocatalytic membranes. Their catalytic performance and mechanism for persulfate activation and degradation of sulfamethoxazole (SMX) were studied systematically. The correlation between preparation parameters and physicochemical properties of the catalytic membranes were investigated. The doping amount of nickel was analyzed and optimized. The effects of operational parameters (such as voltage, flow rate and PMS dosage) on the SMX degradation kinetics were identified. Results suggested that Ni-ZIF-8 nanoparticles were uniformly loaded onto the CNT surface. Under optimal conditions (e.g., Ni doping of 20%, applied voltage of −1.5 V, flow rate of 1.5 mL·min−1 and PMS dosage of 1.5 mmol·L−1), 76.6% removal of 5 mg·L−1 SMX removal can be obtained under single-pass mode. Electron paramagnetic resonance(EPR) and radical quenching tests collectively suggested both ·OH and 1O2 were involved into the SMX degradation process. This study provides new insights on the development of high-performance electrocatalytic membranes for water treatment applications.
-
Key words:
- carbon nanotubes /
- metal-organic framework /
- peroxymonosulfate /
- advanced oxidation /
- sulfamethoxazole.
-
-
[1] 刘鹏霄, 王旭, 冯玲. 自然水环境中抗生素的污染现状、来源及危害研究进展 [J]. 环境工程, 2020, 38(5): 36-42. doi: 10.13205/j.hjgc.202005007 LIU P X, WANG X, FENG L. Occurrences, resources and risk of antibiotics in aquatic environment: A review [J]. Environmental Engineering, 2020, 38(5): 36-42(in Chinese). doi: 10.13205/j.hjgc.202005007
[2] 齐亚兵. 活化过硫酸盐高级氧化法降解抗生素的研究进展 [J]. 化工进展, 2022, 41(12): 6627-6643. QI Y B. Research progress on degradation of antibiotics by activated persulfate advanced oxidation [J]. Chemical Industry and Engineering Progress, 2022, 41(12): 6627-6643(in Chinese).
[3] DAI Y L, YAO Y, LI M H, et al. Carbon nanotube filter functionalized with MIL-101 (Fe) for enhanced flow-through electro-Fenton [J]. Environmental Research, 2022, 204: 112117. doi: 10.1016/j.envres.2021.112117 [4] 赵玲, 刘恒恒, 胡晴, 等. 金属有机骨架材料 MOF-5 催化吸附 SO2 [J]. 环境化学, 2017, 36(9): 1914-1922. doi: 10.7524/j.issn.0254-6108.2016110901 ZHAO L, LIU H H, HU Q, et al. Synthesis of MOF-5 catalysts and their catalytic oxidation of sulfur dioxide [J]. Environmental Chemistry, 2017, 36(9): 1914-1922(in Chinese). doi: 10.7524/j.issn.0254-6108.2016110901
[5] 李小娟, 廖凤珍, 叶兰妹, 等. 金属有机骨架及其衍生材料活化过硫酸盐在水处理中的应用进展 [J]. 化工进展, 2019, 38(10): 4712-4721. doi: 10.16085/j.issn.1000-6613.2019-0163 LI X J, LIAO F Z, YE L M, et al. Progress in the applications of metal-organic frameworks and derivatives activate persulfate in water treatment [J]. Chemical Industry and Engineering Progress, 2019, 38(10): 4712-4721(in Chinese). doi: 10.16085/j.issn.1000-6613.2019-0163
[6] LIU D, GU W Y, ZHOU L, et al. Recent advances in MOF-derived carbon-based nanomaterials for environmental applications in adsorption and catalytic degradation [J]. Chemical Engineering Journal, 2022, 427: 131503. doi: 10.1016/j.cej.2021.131503 [7] 穆寄林, 徐婕, 赵瑨云, 等. ZIF-8的制备及其光催化降解活性红研究 [J]. 化工新型材料, 2022, 50(8): 219-222. MU J L, XU J, ZHAO J Y, et al. Fabrication of ZIF-8 and its photocatalytic degradation of reactive red [J]. New Chemical Materials, 2022, 50(8): 219-222(in Chinese).
[8] 陈丽华, 杜建斌, 王茀学, 等. ZIF-8 复合物光催化去除水体污染物 [J]. 环境化学, 2022, 41(7): 2149-2161. doi: 10.7524/j.issn.0254-6108.2021031401 CHEN L H, DU J B, WANG F X, et al. Photocatalytic removal of water pollutants in ZIF-8 composites [J]. Environmental Chemistry, 2022, 41(7): 2149-2161(in Chinese). doi: 10.7524/j.issn.0254-6108.2021031401
[9] CHO J H, LEE C, HONG S H, et al. Transition metal ion doping on ZIF-8 enhances the electrochemical CO2 reduction reaction [J]. Advanced Materials (Deerfield Beach, Fla. ), 2022, 2208224. [10] REN L H, MA J X, CHEN M, et al. Recent advances in electrocatalytic membrane for the removal of micropollutants from water and wastewater [J]. IScience, 2022, 25(5): 104342. doi: 10.1016/j.isci.2022.104342 [11] JIN L M, YOU S J, DUAN X G, et al. Peroxymonosulfate activation by Fe3O4-MnO2/CNT nanohybrid electroactive filter towards ultrafast micropollutants decontamination: Performance and mechanism [J]. Journal of Hazardous Materials, 2022, 423: 127111. doi: 10.1016/j.jhazmat.2021.127111 [12] ZHENG W T, LIU Y B, LIU W, et al. A novel electrocatalytic filtration system with carbon nanotube supported nanoscale zerovalent copper toward ultrafast oxidation of organic pollutants [J]. Water Research, 2021, 194: 116961. doi: 10.1016/j.watres.2021.116961 [13] SAEEDIRAD R, GANJALI S T, RASHIDI A, et al. Experimental and computational study of organic sulfur removal proficiency of (Ni, Cu, Co)-doped ZIF-8 adsorbents [J]. ChemistrySelect, 2020, 5(1): 231-243. doi: 10.1002/slct.201903233 [14] WANG K D, WU C, WANG F, et al. In-situ insertion of carbon nanotubes into metal-organic frameworks-derived α- Fe2O3 polyhedrons for highly sensitive electrochemical detection of nitrite [J]. Electrochimica Acta, 2018, 285: 128-138. doi: 10.1016/j.electacta.2018.07.228 [15] ZHOU L, LI N, OWENS G, et al. Simultaneous removal of mixed contaminants, copper and norfloxacin, from aqueous solution by ZIF-8 [J]. Chemical Engineering Journal, 2019, 362: 628-637. doi: 10.1016/j.cej.2019.01.068 [16] SHEN B W, WANG B X, ZHU L Y, et al. Properties of cobalt- and nickel-doped zif-8 framework materials and their application in heavy-metal Removal from wastewater [J]. Nanomaterials (Basel, Switzerland), 2020, 10(9): 1636. doi: 10.3390/nano10091636 [17] LI Z Z, SHEN C S, LIU Y B, et al. Carbon nanotube filter functionalized with iron oxychloride for flow-through electro-Fenton [J]. Applied Catalysis B:Environmental, 2020, 260: 118204. doi: 10.1016/j.apcatb.2019.118204 [18] 张格红, 赵平歌, 廖志鹏, 等. 超声强化铋掺杂氧化铟降解偶氮染料废水 [J]. 环境化学, 2016, 35(3): 526-532. doi: 10.7524/j.issn.0254-6108.2016.03.2015080701 ZHANG G H, ZHAO P G, LIAO Z P, et al. Ultrasonic enhanced degradation of AZO dye wastewater by bismuth doped indium oxide [J]. Environmental Chemistry, 2016, 35(3): 526-532(in Chinese). doi: 10.7524/j.issn.0254-6108.2016.03.2015080701
[19] YANG Y, PIGNATELLO J J, MA J, et al. Comparison of halide impacts on the efficiency of contaminant degradation by sulfate and hydroxyl radical-based advanced oxidation processes (AOPs) [J]. Environmental Science & Technology, 2014, 48(4): 2344-2351. [20] YE Z H, PADILLA J A, XURIGUERA E, et al. A highly stable metal-organic framework-engineered FeS2/C nanocatalyst for heterogeneous electro-Fenton treatment: Validation in wastewater at mild pH [J]. Environmental Science & Technology, 2020, 54(7): 4664-4674. [21] DUAN X G, SUN H Q, WANG S B. Metal-free carbocatalysis in advanced oxidation reactions [J]. Accounts of Chemical Research, 2018, 51(3): 678-687. doi: 10.1021/acs.accounts.7b00535 [22] WANG Y, PAN T, YU Y F, et al. A novel peroxymonosulfate (PMS)-enhanced iron coagulation process for simultaneous removal of trace organic pollutants in water [J]. Water Research, 2020, 185: 116136. doi: 10.1016/j.watres.2020.116136 [23] ZHU L L, JI J H, LIU J, et al. Designing 3D-MoS2 sponge as excellent cocatalysts in advanced oxidation processes for pollutant control [J]. Angewandte Chemie (International Ed. in English), 2020, 59(33): 13968-13976. doi: 10.1002/anie.202006059 [24] LOU X Y, FANG C L, GENG Z N, et al. Significantly enhanced base activation of peroxymonosulfate by polyphosphates: Kinetics and mechanism [J]. Chemosphere, 2017, 173: 529-534. doi: 10.1016/j.chemosphere.2017.01.093 [25] MENG H, NIE C Y, LI W L, et al. Insight into the effect of lignocellulosic biomass source on the performance of biochar as persulfate activator for aqueous organic pollutants remediation: Epicarp and mesocarp of citrus peels as examples [J]. Journal of Hazardous Materials, 2020, 399: 123043. doi: 10.1016/j.jhazmat.2020.123043 [26] NIE G, HUANG J, HU Y Z, et al. Heterogeneous catalytic activation of peroxymonosulfate for efficient degradation of organic pollutants by magnetic Cu0/Fe3O4 submicron composites [J]. Chinese Journal of Catalysis, 2017, 38(2): 227-239. doi: 10.1016/S1872-2067(16)62566-4