Pertechnetate immobilization with amorphous iron sulfide
Pertechnetate immobilization with amorphous iron sulfide
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DOI：
10.1524/ract.2008.1528
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发表时间：
2008-01-01
影响因子：
1.8
通讯作者：
Jurisson, S.
中科院分区：
文献类型：
--
作者：
Liu, Y.;Terry, J.;Jurisson, S.
研究了新制备的无定形硫化铁对高锝酸盐（TcO_4 ~（j-））的还原作用。无定形硫化铁（FeS）被证明具有元素组成的FeS 0.07的所有的大小部分和pH值（pzc）= 7.4的零电荷点。FeS在各种缓冲液中的溶解度研究表明，在pH 6.1-9.0范围内，解离的Fe ~（2+）和S ~（2-）的浓度可以忽略不计。FeS还原固定TcO_4 ~-的速度随离子强度的增加而加快，且具有强烈的pH依赖性。在pH值低于pH（pzc），带正电荷的FeS表面与TcO 4-反应更快，并具有更高的固定化产率相对于带负电荷的FeS表面在pH值以上的pH值（pzc）。TcO 4-FeS反应与通过配体交换的表面介导反应一致。采用X射线吸收近边光谱（XANES）、扩展X射线吸收精细结构（EXAFS）、傅里叶变换红外光谱（FT-IR）、和能量色散X射线光谱（EDS），发现主要是TcO 2对FeS还原能力和TcO 4长期稳定性的研究--FeS反应产物在厌氧和有氧环境下显示出潜在的实用性的原位气态（硫化氢气体）固定化技术在固化的TcO 4-通过创建一个FeS渗透反应屏障中的包气带。
The reduction of pertechnetate (TcO4j-) with freshly prepared amorphous iron sulfide was investigated. The amorphous iron sulfide (FeS) was shown to have in elemental composition of FeS0.07 for all of the size fractions and a point of zero charge of pH(pzc) = 7.4. Solubility studies of FeS in various buffers indicated that in the pH range 6.1-9.0, the concentrations of dissociated Fe2+ and S2- were negligible. The reductive immobilization of TcO4- with FeS was shown to be accelerated by increasing ionic strength and strongly pH dependent. At pH values below the pH(pzc), the positively charged FeS surface reacted much faster with TcO4- and had higher immobilization yields relative to the negatively charged FeS surface at pH values above pH(pzc). The TcO4--FeS reaction is consistent with a surface mediated reaction through ligand exchange. The TcO4--FeS reductive immobilization reaction product was characterized by X-ray absorption near edge spectroscopy (XANES), extended X-ray absorption fine structure (EXAFS), Fourier transform infrared spectroscopy (FT-IR), and energy dispersive X-ray spectroscopy (EDS) and found to be predominantly TcO2 studies on the reductive capacity of the FeS and the long term stability of the TcO4--FeS reaction product under both anaerobic and aerobic environments shows the potential utility of the in situ gaseous (hydrogen sulfide gas) immobilization technology in solidification of TcO4- by creating a FeS permeable reaction barrier in the vadose zone.