Development of Technology for Purifying Ion Exchangers from Silicon Impurities During the Processing of Productive Uranium-Containing Solutions

Abstract

The purpose of this work is to investigate the possibility of removing silicon from ion exchangers used in the production cycle, to determine the optimal concentration of alkaline solutions for desilication, and to subsequently analyze the degradation of ion exchangers (resins) employed in sulfuric-acid uranium extraction schemes. The relevance of this study arises from the fact that in Kazakhstan, the process of selective sorption of uranium ions by ion-exchange resins is widely used as the primary method of uranium extraction. During sulphuric acid leaching of uranium ores, silicic acid enters the solution, which has a negative effect on the processes. The transfer of silicic acid into the solution and its participation in the sorption process lead to the gradual accumulation of silicon in anion exchangers, where its maximum content reaches 12-17%. The data was obtained as a result of monitoring ion exchange resins from the technological process. Since silicon is not washed out of the resin during further processing of the anion exchanger, its accumulation leads to a decrease in the resin's uranium capacity and a loss of mechanical strength. The frequency of regeneration of ion exchangers (ion exchange resins) in industrial conditions depends on several factors: the type of ion exchanger, the composition of the initial solution, the operating mode, and the quality requirements for the product obtained. In this regard, the problem of an effective method for reducing the negative impact of silicon in the processing of productive solutions appears to be important and necessary for study.