FIELD: physics.SUBSTANCE: extraction mixture is proposed for extraction of TPE and REE from a highly active raffinate of NPP SNF reprocessing containing an organophosphorus extractant in a polar diluent. As a polar diluent, a water-insoluble limit unsubstituted alcohol or a mixture thereof with saturated hydrocarbons is used. The method involves the combined extraction of TPE and REE with an organophosphorus extractant solution in a polar diluent, washing the extract from impurities and reextraction. The method can be combined with an additional separation of TPE and yttrium REE by using a strong organophosphorus acid or its zirconium salt as an extractant in a separate cycle.EFFECT: high degree of separation of TPE and REE.12 cl, 4 tbl, 3 dwg, 4 ex

Extraction mixture for the recovery of tpe and ree from high-active rafinat of npp snf processing and the method of its use (versions)

FIELD: chemistry.SUBSTANCE: in a method for scandium oxide (ScO) production according to the invention, scandium reextraction is carried out with a solution of hydrofluoric acid, which allows to reduce the losses of the extractant and its transition into scandium oxide, and thereby to obtain pure scandium oxide. At that, by treatment of the scandium fluoride concentrate obtained by this method with an alkaline agent, it is possible to isolate a scandium precipitate with a scandium content in terms of oxide at the level of 85-95%, which allows, with its further oxalate clearing, to obtain scandium oxide with a purity of 99.9÷99.99%.EFFECT: obtaining of a purer scandium oxide with an increased degree of its extraction.6 dwg, 6 ex

Method for scandium oxide production from scandium concentrate

FIELD: chemistry.SUBSTANCE: invention relates to the technology of processing chemical concentrates of natural uranium, involving leaching (dissolving) the concentrate and extracting uranium using tributyl phosphate in a hydrocarbon diluent. The method involves dissolving the concentrate using aqueous nitric acid solution, feeding the obtained aqueous uranyl nitrate solution to the extract outputting step of a stepped extraction unit and extracting uranium with tributyl phosphate in a hydrocarbon diluent. Extraction is carried out by counterflow interaction of the aqueous and organic phases. Concentrate containing thorium impurities in ratio of 1 wt % to uranium is used. During extraction at the extract outputting step, the step for saturating the extractant with uranium is kept at least 87% of the maximum saturation of the extractant with uranium, and a portion of the aqueous phase, which is not more than 60 vol. % of the uranyl nitrate solution fed to the extract outputting step, after one of the extraction steps is removed from the extraction process and fed for dissolving the uranium concentrate.EFFECT: high extraction of uranium and nitric acid from the raffinate.1 tbl

Method of processing chemical concentrate of natural uranium

FIELD: metallurgy.SUBSTANCE: invention relates to hydrometallurgy of rare and radioactive metals and can be used for separation of scandium and thorium, contained in nitrate solutions for processing of scandium-containing raw material. Method for extraction separation of scandium and thorium, contained in nitrate solutions, includes pre-conditioning of initial solution on content of nitric acid to 0.5–1.5 M and nitrate ions to 6–8 M. Method then includes multistage counterflow extraction of scandium from conditioned solution with concentration of scandium 1–10 g/l and thorium 0.01–1 g/l solution of tributyl phosphate in an organic diluent. Further, method includes re-extraction of scandium with water at recycle ratio 4:1 until achieving concentration of scandium in re-extract of 5–20 g/l.EFFECT: providing high degree of separation of scandium and thorium.1 cl, 2 tbl, 2 ex

Extraction separation of scandium and thorium

FIELD: chemistry.SUBSTANCE: invention can be used in technology of selective extracting scandium from concentrates of rare-earth elements (REE). The method for extracting scandium from concentrate of rare-earth elements in the form of an aqueous solution comprises contacting an aqueous solution containing scandium nitrate, REE nitrates, lithium trichloroacetate with a concentration of 1.0-2.0 mol/l with an extractant for 3 minutes. As an extractant, a solution of benzo-15-crown-5 in chloroform is used, and the extraction process is carried out at pH of 3.0-5.0.EFFECT: increasing the coefficients of metal separation and the possibility of carrying out a process of selective extracting scandium from neutral concentrated solutions of REE nitrates before conducting their group separation processes according to a standard process scheme.2 cl, 4 ex

Method of extracting scandium from concentrates of rare-earth elements

FIELD: chemistry. ^ SUBSTANCE: method of cleaning regenerated uranium from thorium, technetium and neptunium, involves extraction of uranyl nitrate from aqueous nitric acid solution with tributylphosphate in an organic diluent. During multi-step countercurrent extraction at the step for output of the extract, the degree of saturation of the extraction agent with uranium is kept not higher than 92.5% of the limiting saturation and equilibrium concentration of nitrate in the aqueous phase is kept not higher than 0.7 mol/l. Concentration of nitric acid in the first stream of the feed aqueous uranyl nitrate solution, fed at the step for output of the extract, is kept not higher than 0.6 mol/l and saturation of the extraction agent with uranium is kept not higher than 92.5% of the limiting saturation at the third or next step, towards the aqueous phase, when the second feed stream of the aqueous uranyl nitrate solution is being fed. ^ EFFECT: high degree of purity of uranium. ^ 5 cl, 5 tbl, 1 ex

Method of cleaning regenerated uranium

FIELD: metallurgy. ^ SUBSTANCE: invention refers to procedures for processing chemical concentrate of natural uranium. The procedure consists in dissolving natural uranium in solution of nitric acid, in directing solution to uranium extraction with tri-butyl-phosphate and hydrocarbon thinner, in washing extract with re-extract and in uranium re-extracting. There is dissolved chemical concentrate of natural uranium with increased content of phosphorus and sulphur. Uranium is extracted from solutions with increased concentration of phosphorus and sulphur and with concentration of nitric acid 3080 g/l to 6075% saturation of extractant with uranium. Also this level of extractant saturation with uranium in the said range in % is maintained not exceeding value equal to (0.3u[HNO3]+51), where [HNO3] is concentration of nitric acid in solution directed to extraction, in g/l. ^ EFFECT: purification of uranium at minimal uranium losses with raffinate. ^ 2 tbl

Procedure for processing chemical concentrate of natural uranium

FIELD: metallurgy. ^ SUBSTANCE: method of extraction reprocessing of restored uranium includes recovery of technetium (VII) in water solution of uranyl- nitrate by nitro-acid solution of diamide at presence of uranium (IV), uranium (VI) extraction by tributyl phosphate in organic vehicle. Additionally technetium (VII) recovery is implemented no more then during 20 minutes at value of excess nitrate-ion relative to its amount in uranyl-nitrate 0.15-0.94 mole/l. ^ EFFECT: method totally excludes formation of sediments of hydrolised uranium, provoking of renewal process shutdown of technetium, and extraction purification of uranium from technetium, requires less consumption of uranium and provides peak value of technetium reduction value. ^ 2 cl, 1 tbl

Stepanov Gennadij Ivanovich

Papers

Method of cleaning regenerated uranium

Procedure for processing chemical concentrate of natural uranium

Method of extraction reprocessing of restored uranium