白金族元素含有の水溶液系の放射線誘起反応に関する研究

Studies of radiation-induced reactions in aqueous solution systems containing platinum group elements

永石 隆二 ; 青柳 登   ; 山田 禮司

Nagaishi, Ryuji; Aoyagi, Noboru; Yamada, Reiji

線などの放射線を用いて、水溶液中の白金族イオンの放射線誘起反応を研究した。アルコールなどを添加しないと放射線照射下でイオンがほとんど還元しない水溶液中でも、アルミナなどの固体酸化物を添加することでその還元が顕著に促進された。また、その還元で生成した微量の沈殿あるいは固体への吸着物が水溶液中の金属イオンの還元をさらに促進することを明らかにした。

Radiation-induced reductions of Pt group ions (Pd, Rh, Pt,..) were studied in aqueous solution systems by using Co-60 -ray or electron beam. A small amount of oxide particles like AlO, SiO or TiO remarkably promoted the reduction of ions, which hardly proceed by ionizing radiations unless additives such as alcohol are present in solution. The promotion was discussed in terms of speciation of Pt group species, and of interaction between the species and the particles. Precipitates/adsorbents of Pt group elements on the particles formed during the reduction were also found to be involved in the further promotion of reduction of metal ions in aqueous solution.