UiO-66-NH2/wood的设计构筑及高效去除水中微量重金属离子性能

矿山开采、 金属冶炼、 新型金属材料的发展以及城市供水系统老化所造成的重金属(铅、 镉、 汞、 砷、 铬、 铜及锌等)污染问题已日趋严重. 传统的水处理方法很难有效地去除低浓度的重金属污染物. 本文以天然木材为载体, 采用溶剂热合成法, 在木材三维孔道中原位合成UiO-66-NH₂金属有机框架材料(MOFs)纳米颗粒, 制备了UiO-66-NH₂/wood复合膜材料. 该复合膜材料对去除水中微量重金属离子(Hg²⁺, Cu²⁺)表现出优异的性能. 当处理速率为1.1×10² L?m^-2?h^-1时, 该复合膜材料去除水中微量重金属离子的效率仍可达到90%以上, 且处理后水中重金属离子含量低于国家饮用水标准. 这可归因于木材本身独特的三维孔道结构, 在提高水通量的同时, 还可以增加水溶液中重金属离子与MOFs颗粒的接触机会, 以及孔道内均匀分布的UiO-66-NH₂ MOFs颗粒中的—NH₂可以与重金属离子通过配位作用相结合. 该UiO-66-NH₂/wood复合膜材料还具有良好的重复利用性, 在连续6次循环使用后其去除效率无明显变化, 有望进行实际应用.

Design and Construction of UiO-66-NH2/wood Composite for Efficient Removal of Trace Heavy Metal Ions from Water

UiO-66-NH₂ Metal-Organic-Frameworks（MOFs） nanoparticles were in situ formed in the 3D low-tortuosity wood lumens by a facile solve-thermal strategy with ZrCl₄ and amino terephthalic acid as precursors. The UiO-66-NH₂/wood membrane showed excellent removal performance for removing heavy metal ions（Hg²⁺， Cu²⁺） in wastewater. The results showed that the removal efficiency for tested heavy metal ions（Hg²⁺， Cu²⁺） is more than 90.0% at the treatment rate of 1.0×10² L?m^-2?h^-1. Wood membrane， as a 3D substrate for anchoring UiO-66-NH₂ nanoparticles， contains numerous elongated and open lumens along the growth direction. On the one hand， it can enhance the water of including heavy metal ions fluxes； on the other hand， it can increase the contact probability of heavy metal ion containments with UiO-66-NH₂ MOFs as water flowing through the membrane. Therefore， the UiO-66-NH₂/wood membrane can efficiently remove trace heavy metal ions from the water. In addition， the UiO-66-NH₂/wood membrane also has good reusability， which is expected to be applied in practical applications.