Anion-exchange behavior of Rf in HCl and HNO solutions

Haba, Hiromitsu; Tsukada, Kazuaki; Asai, Masato; Goto, Shinichi*; Toyoshima, Atsushi; Nishinaka, Ichiro; Akiyama, Kazuhiko; Hirata, Masaru; Ichikawa, Shinichi; Nagame, Yuichiro; Shoji, Yuzuru*; Shigekawa, Mitsuru*; Koike, T.*; Iwasaki, M.*; Shinohara, Atsushi*; Kaneko, Tetsuya*; Maruyama, T.*; Ono, Sawako*; Kudo, Hisaaki*; Oura, Yasuji*; Sueki, Keisuke*; Nakahara, Hiromichi*; Sakama, Minoru*; Yokoyama, Akihiko*; Kratz, J. V.*; Schdel, M.*; Brchle, W.*

We have investigated the sorption behavior of element 104 rutherfordium (Rf) on an anion exchange resin from HCl and HNO solutions. In the HCl experiments, the distribution coefficients of Rf increase with an increase of HCl concentration from 7.0 M to 11.5 M, indicating that anionic species such as [Rf(OH)Cl] or [RfCl] are formed. This sorption behavior of Rf is typical of the group-4 elements Zr and Hf, and is quite different from that of the pseudo-homologue Th. It is also noted that the distribution coefficients decrease in the order Rf, Zr, Hf at 9.0 M HCl, which is consistent with the expected order of ionic radii. On the other hand, Rf appears to behave like Zr and Hf in 8 M HNO not like Pu and Th.