A PRELIMINARY STUDY OF HALLOYSITE RELATED TO URANIUM

It is well know that clay minerals such as montmorillonite or interstratified montmorillonite strongly absorb dissolved uranyl species. 'This paper presents that halloysite could also absorb more uranium and is main uraniferous mineral in some economic uranium deposits. By use of electron microscope. X-ray ditTraction，and infrared spectroscopy, characteristics of uraniferous halloysite is described and recogsized. The results showed that the structural layers of halloysite were changed because of the penetrating and uptaking of uranyl species. The conclusion is that uranly species not only be absorbed by the surface of halloysite but penetrated into structrual layers of halloysite.Under the different geological conditions, The various clay minerals with high .uranium could be formed: montmorillonite or interstratified montmorillonite formed in the alkaline environment, while halloysite formed in the neutro-acid environment.