School of Environmental & Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, China.
School of Environmental & Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, China.
J Hazard Mater. 2020 Jul 15;394:122556. doi: 10.1016/j.jhazmat.2020.122556. Epub 2020 Mar 19.
A novel kind of cationic metal-organic framework(MOF) based mixed-matrix membrane(MMM) namely cationic MOF-MMM was firstly designed and used for simultaneous dispersive membrane extraction(DME) of six phenoxy carboxylic acid(PCA) herbicides from water samples followed by determination using ultrahigh-performance liquid chromatography tandem mass spectrometry. The cationic MOF-MMM was synthesized by soaking the zirconium-based MOFs in a polyvinylidene fluoride(PVDF) solution and further functionalization with quaternary amine groups, viz., UiO-66-NMe MMM. The well-prepared UiO-66-NMe MMM was characterized by FT-IR, SEM, XRD, XPS, NMR and etc. Several main variables influencing the MMM based DME efficiency were investigated and optimized in detail, such as dosage ratio of MOF/PVDF, solution pH, extraction time, coexistent anions and ionic strength. Electrostatic interactions dominated adsorption mechanism between anionic PCAs and cationic UiO-66-NMe MMM, along with ππ conjugation and cation-π bonding, leading to better adsorption performance. Low limits of detection in the range of 0.03-0.59 ng/L and satisfactory recoveries within 80.06-117.40 % for all the PCAs are a reliable witness to demonstrate supreme sensitivity and the applicability of the developed method. By relying on the obtained results, the present work implied cationic MOF-MMM based DME can be a versatile and worthy utility for extraction of pollutants from different water samples with high throughput.
首次设计并使用了一种新型的阳离子金属有机骨架（MOF）基混合基质膜（MMM），即阳离子 MOF-MMM，用于同时从水样中分散膜萃取（DME）六种苯氧羧酸（PCA）除草剂，然后使用超高效液相色谱串联质谱法进行测定。阳离子 MOF-MMM 通过将锆基 MOF 浸泡在聚偏二氟乙烯（PVDF）溶液中并进一步官能化季铵基团，即 UiO-66-NMe MMM 来合成。UiO-66-NMe MMM 的制备过程通过 FT-IR、SEM、XRD、XPS、NMR 等进行了表征。详细研究并优化了影响基于 MMM 的 DME 效率的几个主要变量，例如 MOF/PVDF 的剂量比、溶液 pH 值、萃取时间、共存阴离子和离子强度。阴离子 PCA 与阳离子 UiO-66-NMe MMM 之间的吸附机制主要受静电相互作用支配，同时还存在ππ共轭和阳离子-π键合，导致更好的吸附性能。所有 PCA 的检测限在 0.03-0.59ng/L 范围内，回收率在 80.06-117.40%范围内，这是对超高灵敏度和所开发方法适用性的可靠证明。基于所获得的结果，本工作表明阳离子 MOF-MMM 基 DME 可以作为一种通用且有价值的工具，用于从不同水样中以高通量提取污染物。
