Kim Hyung-Ju, Kim Sung-Jun, Hyeon Seungmi, Kang Han Hi, Lee Keun-Young
Decommissioning Technology Research Division, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 34057, Republic of Korea.
Department of Chemical and Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
ACS Omega. 2020 Aug 4;5(32):20261-20269. doi: 10.1021/acsomega.0c02106. eCollection 2020 Aug 18.
Desalination and nuclide separation, with cesium (Cs), strontium (Sr), and cobalt (Co), using commercial polymeric membranes are investigated under room temperature (298 K) to elucidate the permeation mechanism and possibility of applying commercial membranes to the separation of radioactive nuclides. The physicochemical properties of membranes are characterized by multiple techniques. The thickness of the selective layer and the boundary between the layers of membranes are observed by scanning electron microscopy. The chemical structure of selective and support layers is assessed by direct Fourier transform infrared/attenuated total reflection measurements on membrane samples. Thermogravimetric analysis demonstrates the composition comparison between membranes, which describes the relative amount of selective layers consisting of polyamide. The separation performance of polyamide-based commercial membranes is tested on simulated seawater (35,000 ppm of NaCl) and single- and multi-component aqueous nuclide solutions (10 ppm). Nanofiltration (NF) membranes exhibit a high flux of 160-210 L m h with low 31-64% rejection on the permeation of simulated seawater, while reverse osmosis (RO) membranes display a low flux of 13-22 L m h with nearly 80% rejection. This reveals RO membranes to be more effective for the rejecting nuclides (Cs, Sr, and Co) in dilute aqueous solutions, and NF membranes have advantage on high throughput. RO membranes reject above 93% for single components and even higher for mixed nuclide separation (>98%), and NF membranes permeate high flux above 230 L m h. This study indicates that the desalination membranes (NF and RO) can be potential candidates for nuclide separation with combination.
在室温（298 K）下，研究了使用商用聚合物膜进行脱盐和核素分离，其中包括铯（Cs）、锶（Sr）和钴（Co），以阐明渗透机制以及将商用膜应用于放射性核素分离的可能性。通过多种技术对膜的物理化学性质进行了表征。通过扫描电子显微镜观察选择性层的厚度和膜层之间的边界。通过对膜样品进行直接傅里叶变换红外/衰减全反射测量来评估选择性层和支撑层的化学结构。热重分析表明了膜之间的成分比较，描述了由聚酰胺组成的选择性层的相对含量。在模拟海水（35000 ppm的NaCl）以及单组分和多组分水性核素溶液（10 ppm）上测试了聚酰胺基商用膜的分离性能。纳滤（NF）膜在模拟海水渗透时表现出160 - 210 L m⁻² h⁻¹的高通量以及31 - 64%的低截留率，而反渗透（RO）膜则表现出13 - 22 L m⁻² h⁻¹的低通量以及近80%的截留率。这表明RO膜在稀水溶液中对核素（Cs、Sr和Co）的截留更有效，而NF膜在高通量方面具有优势。RO膜对单组分的截留率高于93%，对混合核素分离的截留率甚至更高（>98%），而NF膜的高通量超过230 L m⁻² h⁻¹。本研究表明，脱盐膜（NF和RO）组合起来可能是核素分离的潜在候选材料。
