Weiyi Cai,Wenwa Weng,Nigel Graham,Xun Liu,Wenzheng Yu,Kening Sun,Ting Liu
MXene (Ti 3 C 2 Tx) can be utilized to modify water-related membranes to provide favorable properties, including pronounced hydrophilicity and chemical stability, and higher flux compared with GO membranes. In order to improve the properties of composite membrane properties, new methods of modifying MXene membranes have been receiving increasing attention. Nowadays, the performance of MXene membranes is mainly limited by methods of modification and stability. In this study, a high-performance composite membrane utilizing MXene (Ti 3 C 2 T x ) was fabricated through a mild and rapid pre-oxidation method. The composite membrane had a high water permeability of ∼690 L m −2 h −1 MPa −1 , a dye rejection of ∼99.9 % and an adsorption rate of only 1 %. Compared with the unoxidized MXene membranes, the composite membranes showed improved the permeation inhibition efficiencies of 42.39 % and 37.51 % for NaCl and MgCl 2 , respectively. The rapid oxidation by Fe(III) formed a composite nano-layer of anatase TiO 2 and magnetite Fe 3 O 4 supported by carbon sheets which protected the internal Ti 3 C 2 T x from further oxidation. The characteristic morphology of a two-dimensional, layer by layer material, was maintained. In addition, the composite membrane demonstrated long-term stability in terms of both structure/appearance and flux in water. Therefore, this work presents new thoughts on the structural tuning and performance optimization of MXene (Ti 3 C 2 T x ) membranes.
Efficient extraction of uranium from seawater is expected to provide virtually infinite fuel sources to power nuclear reactors and thus enable sustainable development of nuclear energy. The extraction efficiency for uranium greatly depends on the availability of active adsorption sites on the adsorbents. Maximization of the utilization rate of the binding sites in the adsorbent is vital for improving adsorption capacity. Herein, micro-redox reactors functioned by Cu(I)/Cu(II) conversion are constructed internally in an adsorbent bearing both amidoxime and carboxyl groups to induce active regeneration of the inactivated binding sites to enhance uranium capture. This adsorbent has high adsorption capacity (962.40 mg-U/g-Ads), superior anti-fouling ability as well as excellent uranium uptake (14.62 mg-U/g-Ads) in natural seawater after 56 days, placing it at the top of high-performance sorbent materials for uranium harvest from seawater.
危险品化学品经营许可证（带存储）