铜/凹凸棒石复合材料高效吸附放射性碘离子性能

Efficient Adsorption of Radioactive Iodide by Copper/Palygorskite Composite

放射性碘是核裂变必然产物。为解决现有铜基吸附剂的吸附容量低、铜利用率低、易脱附等不足,基于凹凸棒石的廉价易得、可交换阳离子富足和层间结构等特性,采用浸渍–还原法将单质Cu负载于凹凸棒石结构中,制备得到Cu/凹凸棒石复合材料,对样品进行表征并考察样品对液相碘离子的吸附性能。研究结果表明,实验制备的Cu/凹凸棒石复合材料约有7.5%掺杂量的纳米铜颗粒负载于凹凸棒石层间结构中。与传统铜基吸附剂相比,该材料具有高达116.1 mg/g的碘离子吸附量以及72%铜利用率;并且可在中性、弱酸性以及SO_(4)^(2–)、NO_(3)^(–)、Na^(+)、Mg^(+)等干扰离子共存的环境下使用。此外,得益于铜负载凹凸棒石结构内,该复合材料展现出较强的抗氧化性能,且吸附后产物也具有较强的稳定性。

To solve the disadvantages of low adsorption capacity,low utilization and easily desorption of traditional Cu-based adsorbents for radioactive iodide,the inevitable product of nuclear fission,Cu/Palygorskite composite(Cu@PAL)was synthesized through impregnation-reduction method,characterized and applied to remove I−anions based on the excellent traits of PAL,such as cheap,abundant exchangeable cations and interstratified structure.Results indicate that there are about 7.5wt% copper nanoparticles loaded into PAL for the as-prepared composite.Cu@PAL has better performance in the adsorption of iodide as compared with traditional Cu-based adsorbents,with 72%utilization efficiency and excellent adsorption capacity of 116.1 mg/g.Cu@PAL is suitable for adsorption of I−anions under the conditions of neutral,weak acid and the coexistence of interference ions.In addition,the composite exhibit strong oxidation resistance,and the adsorbed product also has strong stability due to the copper stored in the PAL structure.