Um Wooyong, Serne R J R Jeffrey, Krupka K M Kenneth M
Pacific Northwest National Laboratory, Applied Geology and Geochemistry, Richland, WA 99352, USA.
Water Res. 2004 Apr;38(8):2009-16. doi: 10.1016/j.watres.2004.01.026.
A series of adsorption and desorption experiments were completed to determine the linearity and reversibility of iodide adsorption onto sediment at the Hanford Site in southeastern Washington. Adsorption experiments conducted with Hanford formation sediment and groundwater spiked with dissolved (125)I (as an analog tracer for (129)I) indicated that iodide adsorption was very low (0.2 mL/g) at pH 7.5 and could be represented by a linear isotherm up to a total concentration of 100 mg/L dissolved iodide. The results of desorption experiments revealed that up to 60% of adsorbed iodide was readily desorbed after 14 days by iodide-free groundwater. Because iodide adsorption was considered to be partially reversible, even though small amount of initial iodide is retarded by adsorption at mineral-water interfaces, the weak adsorption affinity results in release of iodide when iodide-free pore waters and uncontaminated groundwaters contact the contaminated sediments in the vadose zone and aquifer systems.
在华盛顿州东南部的汉福德场地，进行了一系列吸附和解吸实验，以确定沉积物对碘化物吸附的线性和可逆性。用汉福德地层沉积物和添加了溶解态（125）I（作为（129）I的模拟示踪剂）的地下水进行的吸附实验表明，在pH值为7.5时，碘化物的吸附量非常低（0.2 mL/g），并且在溶解碘化物总浓度达到100 mg/L之前，可以用线性等温线来表示。解吸实验结果表明，14天后，高达60%的吸附碘化物能被无碘地下水轻易解吸。由于碘化物的吸附被认为是部分可逆的，所以尽管少量初始碘化物在矿物-水界面处因吸附而滞留，但当无碘孔隙水和未受污染的地下水与包气带和含水层系统中的受污染沉积物接触时，较弱的吸附亲和力会导致碘化物释放。
