Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology , Shanghai 200237, China.
ACS Appl Mater Interfaces. 2015 Jan 14;7(1):223-31. doi: 10.1021/am5059074. Epub 2014 Dec 24.
Though many efforts have been devoted to the adsorptive removal of hazardous materials of organophosphorus pesticides (OPs), it is still highly desirable to develop novel adsorbents with high adsorption capacities. In the current work, the removal of two representative OPs, glyphosate (GP) and glufosinate (GF), was investigated by the exceptionally stable Zr-based MOFs of UiO-67. The abundant Zr-OH groups, resulting from the missing-linker induced terminal hydroxyl groups and the inherent bridging ones in Zr-O clusters of UiO-67 particles, served as natural anchorages for efficient GP and GF capture in relation with their high affinity toward phosphoric groups in OPs. The correlation between the most significant parameters such as contact time, OPs concentration, adsorbent dose, pH, as well as ionic strength with the adsorption capacities was optimized, and the effects of these parameters on the removal efficiency of GP and GF from the polluted aqueous solution were investigated. The adsorption of GP on UiO-67 was faster than that of GF, and a pseudo-second-order rate equation effectively described the uptake kinetics. The Langmuir model exhibited a better fit to adsorption isotherm than the Freundlich model. Thanks to the strong affinity and adequate pore size, the adsorption capacities in UiO-67 approached as high as 3.18 mmol (537 mg) g(-1) for GP and 1.98 mmol (360 mg) g(-1) for GF, which were much higher than those of many other reported adsorbents. The excellent adsorption characteristics of the current adsorbents toward OPs were preserved in a wide pH window and high concentration of the background electrolytes. These prefigured the promising potentials of UiO-67 as novel adsorbent for the efficient removal of OPs from aqueous solution.
尽管人们已经付出了许多努力来去除有机磷农药（OPs）等有害物质，但开发具有高吸附容量的新型吸附剂仍然是非常可取的。在目前的工作中，通过特别稳定的 Zr 基 MOF UiO-67 研究了两种代表性的 OPs，草甘膦（GP）和草铵膦（GF）的去除。UiO-67 颗粒中缺失连接子诱导的末端羟基和固有桥联的 Zr-O 簇中的丰富 Zr-OH 基团，作为与 OPs 中磷酸基团的高亲和力相关的高效 GP 和 GF 捕获的天然锚固点。优化了接触时间、OPs 浓度、吸附剂剂量、pH 值以及离子强度等最重要参数与吸附容量之间的相关性，并研究了这些参数对从受污染水溶液中去除 GP 和 GF 的去除效率的影响。GP 在 UiO-67 上的吸附速度快于 GF，准二级速率方程有效地描述了吸附动力学。Langmuir 模型比 Freundlich 模型更能拟合吸附等温线。由于强亲和力和适当的孔径，UiO-67 的吸附容量高达 3.18 mmol（537 mg）g(-1)用于 GP 和 1.98 mmol（360 mg）g(-1)用于 GF，远高于许多其他报道的吸附剂。当前吸附剂对 OPs 的优异吸附特性在宽 pH 窗口和高背景电解质浓度下得以保留。这些预示着 UiO-67 作为从水溶液中有效去除 OPs 的新型吸附剂具有广阔的应用前景。
