TO THE QUESTION OF RECOVERY OF URANIUM FROM RAW MATERIALS

The problem of extracting uranium from difficult-to-hide ores can be attributed to the most important scientific and technical problems facing the modern uranium mining industry. One of the areas of modern scientific and technological progress in the development of radioactive ore deposits is using of a practically non-waste method of mining uranium - underground leaching (UL). A great interest to the method of underground leaching is determined by the positive experience of its application and high technical and economic indicators. In Kazakhstanin underground uranium leachinga sulfuric acidis used as a leaching reagent. In this case, the degree of transition of uranium to the productive solution can be due to a variety of reasons, primarily related to the physico-chemical properties of uranium-containing minerals. Thus, the use of sulfuric acid as a leaching reagent allows the extraction of only uranium (VI) compounds, since uranium compounds (IV) in sulfuric acid do not dissolve. To convert uranium (VI) to uranium (IV), oxidizers are used in industry, most often-ferric compounds. In this regard, the main problem of increasing the extraction of uranium in underground leaching is the transfer of uranium (IV) to a soluble state. Analysis of scientific and technical literature has shown that recently one of the main directions for increasing the extraction of uranium from poorly soluble ores is the use of intensifiers that allow the most complete transfer of uranium from one valence state to another.In the article, the catalyst "M-1", which is a compound of transition metals, is considered as an intensifier. Comparative data are given for the study of agitation leaching of uranium from ore in the presence of a number of oxidants. Priorityuseofthe"M-1" catalystwasnoted. Sorption methods are used to extract uranium from productive solutions. Ion exchange has certain advantages over others, since it allows to extract uranium from solutions of various concentrations. Comparison of the kinetic dependencies of the sorption extraction of uranium by the ionites of Purolite A-500 and Ambersep-920 from the productive solutions of leaching of uranium-bearing ore in the presence of the "M1"catalyst showed that they differ insignificantly. The values of activation energy for sorption of uranium on these ion exchangers and diffusion coefficients are calculated. Their magnitude is characteristic of a mixed external and internal diffusion process type. In the literature, there are data on the use of natural sorbents for the extraction of uranium from productive solutions with low content of uranium. The advantages of such sorbents are their low cost. Within the framework of the present work, the possibility of sorption of uranium from productive solutions by natural zeolite and schungite in comparison with synthetic sorbents is investigated.