CS215174B1 - Process for preparing a uranium compound - Google Patents

Abstract

The invention provides a method for preparing a uranium compound in the form of a precipitate from carbonate solutions. Carbonate solutions, or rather solutions containing carbonates with a determined concentration of carbonates, are heated to a temperature of 150° C to 250° C. A uranium compound is formed, which is separated from the mother solution in the form of a precipitate. The method according to the invention is intended for the separation of uranium from carbonate solutions, especially in the processing of uranium ores.

Description

The invention provides a process for the preparation of a uranium compound in the form of a precipitate from uranium containing carbonate solutions.

The processing of uranium ores produces carbonate solutions which are mixtures of carbonates and other anions such as sulfates, nitrates or chlorides. These solutions contain uranium in the form of carbonate complexes. To separate uranium from solution, carbonate complexes are usually decomposed with sulfuric acid. The carbonate-free solution is most often precipitated with ammonia to give the resulting product ammonium dichorate. In the es process it consumes sulfuric acid, ammonia and soluble carbonates. The consumption of soluble carbonates, sulfuric acid and ammonia affects the material cost of the process.

These drawbacks are overcome by the process for preparing the uranium compound in the form of a precipitate from the uranium-containing carbonate solutions of the invention. The principle is that the uranium-containing carbonate solution is heated to a temperature of 100-250 ° C, the carbonate concentration is adjusted in the range from 0.0003 to 1.0 m and the uranium compound is separated from the mother liquor in the form of a precipitate.

The process according to the invention can save chemicals by avoiding acidification of the original solution, since the presence of carbonates is a prerequisite for the success of the process. This is associated with savings in both sulfuric acid and soluble carbonates. It is not necessary to use ammonia to transfer uranium to the solid phase. In the process, uranium compounds are formed directly, which deposit well and separate well from the mother liquor. The mother liquor can be returned to the process after the uranium precipitate has been separated and the necessary ion concentration has been adjusted.

The method of the invention illustrates five experiments performed.

Example 1

A solution of 0.2 sodného β sodium per e 0.2 M sodium carbonate containing 32.5 g uranium per liter was treated at the temperatures below. Created ee precipitate and po

Even the following amounts of uranium remained in the solution:

temperature (° C) 140 155

170

190 U balance in solution (g.l -1) -2.0 '0.16 0.13 0.08

Example 2

A solution of 0.2 M sodium sulfate and 0.5 M sodium carbonate containing 32.5 g uranium per liter was treated at the following temperatures. A uranium-containing precipitate precipitated from the solution.

After treatment, the following amount of uranium and temperature (° C) of 140 1SS remained in solution

170

190

210 U balance in solution (gl ^-1 ) 13.99 12.63

9.34

6.44

3.63

Example 3

A solution of the original concentration of 1.1 M total sulphates, 0.145 M total carbonates and 5.33 g uranium per liter was treated at the indicated temperatures, a uranium-containing precipitate fell out of solution for 30 minutes and the following amounts of uranium remained in solution:

temperature (° C) balance U in solution (g.1 “^)

110

120

130

150

160

4.32

0.534

0,066

0,023

0,022

Example 4

A solution of 1.0 M total sulphate, 0.265 M total carbonate, and containing 7.79 g uranium per liter was treated at the following temperatures and from the solution and separated by a uranium-containing precipitate, the following amounts of uranium remained in solution after 60 minutes. :

temperature (° C) 110

120

130

140

ISO remaining U in solution (gl ^-1 ) 6.96 4.8 0.020 0.016 0.014

Example 5

A solution with an initial concentration of 1.3 M total sulfates, 0.0376 M total carbonates containing 7.66 g uranium per liter was treated at the temperatures indicated below. Upon reaching aa, the uranium-containing precipitate separated and the following amounts of uranium remained in solution:

temperature (° C) balance U in solution (gl ^-1 ),

170

180

190

200

AND

220

230

3.2

0.94

0.20

0,045

0.015

0.010

215Π4

The process according to the invention is primarily intended for the separation of uranium from uranium-containing carbonate solutions, particularly in the treatment of uranium ores.

Claims (1)

A process for the preparation of a uranium compound in the form of a precipitate from uranium-containing carbonate solutions, characterized in that The uranium is heated to a temperature of 100 to 250 ° C, adjusting carbonate concentrations between 0.0001 M and 1.0 M to produce a uranium compound which is separated from the mother liquor as a precipitate. Severography, n. P. Plant 7, Moal