Service Center of Public Technology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, PR China.
Department of Chemistry and Applied Chemistry, Changji University, Changji, 831100, Xinjiang, PR China.
Environ Pollut. 2021 Jan 1;268(Pt B):115705. doi: 10.1016/j.envpol.2020.115705. Epub 2020 Oct 4.
The exploitation of a new adsorbent with a high adsorption performance and recyclability is of great practical significance for the treatment of wastewater containing mercury ions. In this study, a novel membrane adsorbent was fabricated by blending MoS nanosheets into a PVDF polymer matrix (P-PVDF/MoS) followed by non-solvent-induced phase conversion. This material was able to bind mercury ions and was not affected by the solution ionic strength, co-existing anions, or interfering heavy metal ions. The optimal pH range for mercury ion elimination was 4.5-6.0, and P-PVDF/MoS exhibited a maximum adsorption capacity of 578 mg g. The pseudo-second-order adsorption kinetics and Langmuir isotherm models best described the adsorption process. The adsorption mechanism was mainly monolayer chemisorption, for which the S groups were the major active sites. Furthermore, the membrane could be removed from the aqueous solution easily using tweezers, and the removal efficiency of mercury ions remained over 90% after ten cycles. This study suggests that the inexpensive and recyclable P-PVDF/MoS membranes can be used for the efficient removal of heavy metal ions from wastewater at a large scale.
开发一种具有高吸附性能和可重复使用性的新型吸附剂，对于处理含汞离子的废水具有重要的实际意义。本研究通过将 MoS 纳米片掺入聚偏氟乙烯（PVDF）聚合物基质中（P-PVDF/MoS），然后通过非溶剂诱导相转化制备了一种新型膜吸附剂。该材料能够结合汞离子，不受溶液离子强度、共存阴离子或干扰重金属离子的影响。去除汞离子的最佳 pH 范围为 4.5-6.0，P-PVDF/MoS 的最大吸附容量为 578mg/g。吸附动力学过程符合准二级动力学模型，吸附等温线符合 Langmuir 模型。吸附机制主要为单层化学吸附，其中 S 基团是主要的活性位点。此外，该膜可以用镊子轻松从水溶液中去除，并且在经过十次循环后，对汞离子的去除效率仍保持在 90%以上。本研究表明，这种廉价且可重复使用的 P-PVDF/MoS 膜可以用于大规模高效去除废水中的重金属离子。
