A half-wave rectified alternating current electrochemical method for uranium extraction from seawater
A half-wave rectified alternating current electrochemical method for uranium extraction from seawater
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DOI：
10.1038/nenergy.2017.7
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发表时间：
2017-04-01
期刊：
影响因子：
56.7
通讯作者：
Cui, Yi
中科院分区：
文献类型：
--
作者：
Liu, Chong;Hsu, Po-Chun;Cui, Yi
总体而言，海水中的铀含量是陆地上的数百倍，但由于海水中的铀浓度较低(类似于3ppb)和高盐度背景，提取用于核能发电的铀是具有挑战性的。目前基于吸附材料的方法由于其表面的物理化学吸附性质而受到限制。本文采用半波整流交流电化学法(HW-ACE)提取海水中的铀。胺肟的官能化使其能够与铀酰离子特异结合，而电场可以将离子迁移到电极上，诱导铀化合物的电沉积，形成电荷中性物种。萃取不受电极表面积的限制，外加电压的交替方式防止了不需要的阳离子堵塞活性部位，避免了水的分裂。在没有饱和的情况下，HW-ACE方法的铀提取能力(1,932 mg g(-1))比使用添加铀的海水的传统物理化学方法高9倍(1,932 mg g(-1))，动力学速度快4倍。
In total there is hundreds of times more uranium in sea water than on land, but extracting it for use in nuclear power generation is challenging due to its low concentration (similar to 3 ppb) and the high salinity background. Current approaches based on sorbent materials are limited due to their surface-based physicochemical adsorption nature. Here we use a half-wave rectified alternating current electrochemical (HW-ACE) method for uranium extraction from seawater based on an amidoxime-functionalized carbon electrode. The amidoxime functionalization enables surface specific binding to uranyl ions, while the electric field can migrate the ions to the electrode and induce electrodeposition of uranium compounds, forming charge-neutral species. Extraction is not limited by the electrode surface area, and the alternating manner of the applied voltage prevents unwanted cations from blocking the active sites and avoids water splitting. The HW-ACE method achieved a ninefold higher uranium extraction capacity (1,932 mg g(-1)) without saturation and fourfold faster kinetics than conventional physicochemical methods using uranium-spiked sea water.