Preparation of Hydrophilic and Selective Adsorbents and Their Uranium Uptake Performance in Seawater

铀在海水中的溶解浓度约为3毫克/立方米，以铀酰三氧化二铀离子的形式存在。原子能发电厂不断需要铀资源;因此，海水中的45亿吨铀对原子能利用至关重要。偕胺肟基被认为是从海水中回收铀的理想基团，偕胺肟基对海水中的铀酰有很强的吸附作用，且吸附的铀酰离子易于用盐酸洗脱。为了提高铀的吸附率，将丙烯腈和甲基丙烯酸接枝到聚丙烯或聚乙烯纤维上，然后与羟胺反应，将生成的氰基转化为偕胺肟基，制备了亲水性偕胺肟纤维。海水中铀的吸附量是用浮动接触法测定的。在接触60天后，1小时的酰胺肟化提供了每kg吸附剂1. 7 g-U的吸附量。钒的吸附量是铀的2倍。

Uranium is dissolved in seawater at a concentration of about 3 mg/m3 in the ionic form of uranyl tricarbonate ion. Atomic power plants continuously require uranium resources ; therefore, the 4.5 billion tons of total uranium in seawater will be essential for atomic power utilization. The amidoxime group has been selected as a promising group for uranium recovery from seawater ; the amidoxime group adsorbes uranyl species specifically from seawater, and the adsorbed uranyl ions are easily eluted with hydrochloric acid. To improve the adsorption rate of uranium, hydrophilic amidoxime fibers were prepared by cografting of methacrylic acid with acrylonitrile onto polypropylene or polyethylene fibers and subsequent conversion of the produced cyano group to an amidoxime group by reaction with hydroxylamine. The amount of uranium adsorbed in seawater was determined by means of a floating-contact mode. One hour of amidoximation provided an adsorbed amount of 1.7 g-U per kg of adsorbent after 60 days of contact. The amount of vanadium adsorbed was twice that of uranium.