Recovery and Removal of Uranium by Immobilized Kakishibu Tannin

点击翻译按钮获取中文摘要

Some attempts were made to recover and remove of uranium that may be present in refinning effluents by using immobilized kakishibu tannin. Tannin compounds having multiple adjacent hydroxy groups have an extremely high affinity for uranium and thorium.Kakishibu is the exptracted juice of uuripe astringent persimmon fruit, and it contains large quantities of tannin compounds. Kakishibu is easily immobilized with various aldehyde solutions. The immobilized kakishibu presents an extremely high affinity to uranium and thorium. One gram of the immobilized kakishibu absorbed 1.7g of uranium.Removal tests for uranium existing-in uranium refining wastewater were carried out at the Ningyo-toge Station of the Power Reactor and Nuclear Fuel Development Corporation. The immobilized kakishibu can recover and remove uranium from uranium refining wastewater with high efficiency. The uranium retained on the adsorbent can be quantitatively and easily eluted with a very dilute hydrochloric acid. The adsorbent can be used repeatedly in the adsorption-desorption cycle.