Development of the removal system of toxic metal ions for the reduction of environmental load

本项目的目的是开发有毒金属离子的去除系统，以减少环境负荷。在2006年至2007年期间，使用二氧化钛和碳酸钾通过助熔剂（钾离子交换剂）法尝试合成离子交换材料（四钛酸钾纤维）。通过对钛酸钾物理性质的研究，采用盐酸洗涤法将钛酸二氢钾改性为钛酸二氢钾纤维。氢型钛酸盐用作碱金属、碱土金属和过渡金属三种金属族的离子交换剂。2007年和2008年，对这些金属离子族（碱金属离子族：锂离子、钠离子、钾离子、铷离子、铯离子）的分离进行了研究。碱土金属离子组：镁离子、钙离子、锶离子、钡离子。过渡金属离子基团：铜离子、镍离子、锌离子）通过柱法检测以检查分离这些金属离子的能力。该方法可用于高放废物中铯、锶离子的分离，并可使长寿命放射性废物中的铯、锶离子的含量降低。最后，分离出有毒金属离子，可以与其他物质分离。

The purpose of this project is the development of the removal system of toxic metal ions for the reduction of environmental load. The synthesis of the ion exchange material (potassium tetratitanate fiber) was tried by flux (potassium molybdate) method using titanium dioxide and potassium carbonate between 2006 and 2007. After the investigation of physical characters of the potassium tetratitanate, this materials was changed to dihydrogen tetratitanate hydrate fibers by washing hydrochloric acid. The hydrogen type titanate was used to the ion exchanger for the three metal groups, such as alkali metal group, alkaline earth metal group, and transition metal group. These metals had high ion exchange ability by batch wise method.In 2007 and 2008, the separation of these group metal ions (alkali metal ion group: lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions. Alkaline earth metal ion group: magnesium ions, calcium ions, strontium ions, barium ions. Transition metal ion group: copper ions, nickel ions, zinc ions) were examined by column method to check the ability for the separation of these metal ions. The separation factor between two metal ions which belong to the same groups is very high and this method will be used to the removal system of toxic metal ions for the reduction of environmental load.From these results, this method will be applied for the separation of cesium and strontium ions in high level radioactive waste, and the toxic long life radioactive waste can be decrease compare than those before the treatment. Finally, the separation of toxic metal ions can be separate from other materials.