Abstract

An alternative procedure was developed for selective leaching of uranium from carbonate-rich black shale of southwestern Sinai (0.16% U₃O₈). Uranium was present in the rock sample in the hexavalent state. This method is based on using a mixed citric acid/calcium citrate reagent so as to leave the carbonate, vanadium, and copper almost intact for the later processing. The influence of the concentration of citric acid/Ca citrate, molar ratio, grain size, pH of the leach liquor solutions, solid-to-liquid ratio, leaching time, and temperature was investigated in order to find optimum conditions. From the leach liquor, uranium can be recovered by addition of isopropyl alcohol.

中文翻译：

---

从西奈西南部El-Allouga的Um-Bogma组，富含碳酸盐的黑色页岩中选择性浸出铀的替代方法

摘要

开发了一种替代方法，用于从西奈西南部富含碳酸盐的黑色页岩（0.16％U ₃ O ₈）中选择性浸出铀。铀以六价态存在于岩石样品中。该方法基于使用柠檬酸/柠檬酸钙的混合试剂，以便几乎保留碳酸盐，钒和铜的完整性，以备后续处理。为了找到最佳条件，研究了柠檬酸/柠檬酸钙的浓度，摩尔比，粒度，浸出液的pH，固液比，浸出时间和温度的影响。从浸出液中，可以通过添加异丙醇来回收铀。