Safe disposal of nuclear waste in a geologic repository will rely on natural geologic features and engineered barriers to greatly retard the movement of radionuclides from the repository. Clay minerals including bentonite are effective in retarding the migration of many radionuclides, but are ineffective for anionic radionuclides, of which pertechnetate is of particular concern owing to its relatively long half-life and the lack of natural isotopes that dilute it. Activated carbon is proposed as an additive material for reducing pertechnetate mobility in the nearfield. Activated carbon materials of different origins quantitatively sorb pertechnetate from aqueous solution under oxidizing conditions during the first day of contact, and sequential extraction showed that 73% of this technetium is in the strongly bound fraction. X-ray photoelectron spectra (XPS) and extended X-ray absorption fine structure (EXAFS) spectra both demonstrated that no reduction of technetium occurred in the studied systems. The interaction of technetium with a composite material consisting of bentonite and activated carbon was studied at the first time. Effective technetium sorption was shown, with distribution coefficients (Kd) up to 740 cm^3. g^-1.

在地质处置库中安全处置核废料将取决于自然的地质特征和工程屏障，以大大阻止放射性核素从处置库中的迁移。包括膨润土在内的粘土矿物可有效抑制许多放射性核素的迁移，但对阴离子放射性核素则无效，由于高net酸盐的半衰期相对较长且缺乏天然同位素对其进行稀释，因此高per酸盐特别值得关注。提出了活性炭作为降低近场中高tech酸盐迁移率的添加剂。在接触的第一天，不同来源的活性炭材料在氧化条件下会从水溶液中定量吸附高tech酸盐，顺序萃取表明该showed中有73％位于强结合部分。X射线光电子能谱（XPS）和扩展X射线吸收精细结构（EXAFS）光谱均表明在所研究的系统中no未发生还原。首次研究了with与膨润土和活性炭组成的复合材料之间的相互作用。显示了有效的tech吸附，分布系数（Kd）高达740 cm^3.  g ^-1。