Optimization and evaluation of mixed-bed chemisorbents for extracting fission and activation products from marine and fresh waters.
Optimization and evaluation of mixed-bed chemisorbents for extracting fission and activation products from marine and fresh waters.
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用于从海洋和淡水中提取裂变和活化产物的混合床化学吸附剂的优化和评估。
DOI：
10.1016/j.aca.2011.08.017
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发表时间：
2011
影响因子：
6.2
通讯作者：
Schwantes,JonM
中科院分区：
文献类型：
--
作者：
Johnson,BryceE;Santschi,PeterH;Addleman,RaymondShane;Douglas,Matt;Davidson,Joe;Fryxell,GlenE;Schwantes,JonM
需要化学选择性化学吸附剂来监测天然和工程水中稳定和放射性污染物的人为释放。在这里，研究了几种单独的和混合的化学吸附剂从海洋和沿海水域提取选定的裂变和激活产物元素的能力，包括Co、Zr、Ru、Ag、Te、Sb、Ba、Cs、Ce、Eu、Pa、Np和Th。传统的氧化锰和氰基高铁酸盐吸附剂，包括商用的Anfezh和六氰基钴(II)钾(KCFC)，与新型纳米结构表面(称为介孔载体上的自组装单分子膜或SAMs)一起进行了测试，表面官能化的部分包括硫醇、二膦酸(DiPhos-)、甲基-3，4-羟基吡啶酮(HOPO-)和氰基高铁酸盐。在一系列与环境有关的条件下，测量了合成和天然淡水和咸水的萃取效率，作为盐度、有机含量、温度、流速和样品大小的函数。流速对萃取效率的影响，从1到70mLmin−1，对影响吸附过程的机理的速率限制提供了一些见解。优化的吸附剂-配位体化学混合物提供了良好的保留所有的目标元素，除了Ba和Sb。被测化学吸附剂的混合物，包括MnO_2/AnFezh和MnO_2/KfC/硫醇(1-3 mM)-SAMMS，提取了所研究的11个目标元素中的8个，效率高于80%，而MnO_2/AnFezh/硫醇(75-150μm)-SAMMS混合物能够提取11个目标元素中的7个，效率超过90%。这里产生的结果表明，如果从含有可变数量的DOM的淡水中取样，而不是从咸水环境中采集样品，则在实验设计中应较少考虑流速。相对于被测试的任何单一类型的化学吸附剂的能力，几种吸附剂的优化混合物能够增加可以有效且同时从天然水中提取的元素的数量。
Chemically selective chemisorbents are needed to monitor natural and engineered waters for anthropogenic releases of stable and radioactive contaminants. Here, a number of individual and mixtures of chemisorbents were investigated for their ability to extract select fission and activation product elements from marine and coastal waters, including Co, Zr, Ru, Ag, Te, Sb, Ba, Cs, Ce, Eu, Pa, Np, and Th. Conventional manganese oxide and cyanoferrate sorbents, including commercially available Anfezh and potassium hexacyanocobalt(II) ferrate(II) (KCFC), were tested along with novel nano-structured surfaces (known as Self Assembled Monolayers on Mesoporous Supports or SAMMS) functionalized with a variety of moieties including thiol, diphosphonic acid (DiPhos-), methyl-3,4 hydroxypyridinone (HOPO-), and cyanoferrate. Extraction efficiencies were measured as a function of salinity, organic content, temperature, flow rate and sample size for both synthetic and natural fresh and saline waters under a range of environmentally relevant conditions. The effect of flow rate on extraction efficiency, from 1 to 70mLmin−1, provided some insight on rate limitations of mechanisms affecting sorption processes. Optimized mixtures of sorbent–ligand chemistries afforded excellent retention of all target elements, except, Ba and Sb. Mixtures of tested chemisorbents, including MnO2/Anfezh and MnO2/KCFC/Thiol (1–3mm)-SAMMS, extracted 8 of the 11 target elements studied to better than 80% efficiency, while a mixture of MnO2/Anfezh/Thiol (75–150μm)-SAMMS mixture was able to extract 7 of the 11 target elements to better than 90%. Results generated here indicate that flow rate should be less of a consideration for experimental design if sampling from fresh water containing variable amounts of DOM, rather than collecting samples from salt water environments. Relative to the capability of any single type of chemisorbent tested, optimized mixtures of several sorbents are able to increase the number of elements that can be efficiently and simultaneously extracted from natural waters.