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2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
L. M. Slater
Nuclear Science and Engineering | Volume 17 | Number 4 | December 1963 | Pages 576-585
Technical Paper | doi.org/10.13182/NSE63-A18450
Articles are hosted by Taylor and Francis Online.
Cesium (<5 × 10-3M) can be extracted from aqueous sodium iodide solutions into equal volumes of 0.2M I2 in nitrobenzene at 25°C with extraction coefficients as great as two thousand. Cesium may be back-extracted by equilibration with ∼4M or stronger nitric acid. The separation factor of cesium (∼10-7M) from sodium in extractions made from sodium iodide solutions into equal volumes of 0.2M I2 in nitrobenzene at 25°C remained fairly constant at ∼1500 up to ∼1M NaI. It decreased to ∼100 at 8M NaI. At this point the cesium extraction coefficient was still greater than two. The decrease in the separation factor is seen as largely due to the decrease in the ratio of the activity coefficient of the cesium ion to that of the sodium ion in the aqueous phase. Extraction data for sodium and cesium from various solutions and under a variety of conditions are given. Sodium and cesium ions are seen extracted as ion association compounds with triiodide ions. Polyiodide ions as complex as the enneaiodide are formed subsequently in the organic phase. Sodium and cesium polyiodides are thought to be essentially ionized in nitrobenzene. Extractions are believed to be the result of the “squeezing out” from aqueous solution into nitrobenzene of ion pairs of cations of small ionic potential together with large anions that are compatible with the organic solvent. The driving force behind the extractions comes largely from the reformation of the hydrogen bonded water structure in the relatively large cavities left by the extracted ion pairs.
