辐射接枝技术的应用:日本海水提铀研究的进展及现状

Application of Radiation Grafting:Progress and Status of the Extraction of Uranium From Seawater in Japan

辐射技术已广泛应用于各种新材料的制备,包括使用辐射接枝技术将具有特殊性能的官能团嫁接到基体材料上,用于金属元素的分离。自20世纪80年代后期以来,日本进行了利用辐射接枝技术制备以偕胺肟为官能团的吸附剂从海水中提取铀的研究。在30天的大型海洋实验中,取得了1.5g/kg的吸附效率。日本进行的初步的经济性评估表明,采用这种技术提铀的费用大约为铀市场现货价格(spot price)的2～3倍。如果进一步优化吸附剂的制备过程,提高吸附剂的吸附容量、选择性和稳定性,提取费用还可降低,从而使海水提铀更具有竞争力和吸引力。作为辐射技术应用的例子,本文简要介绍日本海水提铀的研究进展及现状,并对海水提铀的研究与开发工作提出若干建议。

Radiation grafting has been widely used in the preparation of new materials, in- cluding the use of radiation-induced grafting to incorporate special functional groups onto base materials for separations of metal elements. Since the late 1980＇s, research has been conducted in Japan to prepare sorbents with amidoxime groups for the extraction of uranium from seawater. A sorption efficiency of 1.5 g/kg was achieved in large-scale marine tests that lasted for 30 days. Preliminary cost evaluation conducted in Japan indicates that urani- um in seawater could be collected with this technology at a price that is approximately 2-3 times the market spot price of uranium. The cost of extraction could be further reduced by optimizing the preparation of the sorbents, increasing the sorption capacity and selectivity, and improving the chemical and mechanical stability of the sorbents, making the technology of the extraction of uranium from seawater more competitive and attractive. As an example of the application of radiation grafting, this paper briefly introduces the research progress and status on the extraction of uranium from seawater in Japan. Recommendations on fur- ther research and development in this field are also discussed.