Method of ion-exchange uranium extraction from sulfuric solutions and pulps

FIELD: metallurgy.

SUBSTANCE: method includes uranium sorption by anion exchange resin, uranium de-sorption from saturated anion exchange resin by sulphuric acid and obtaining finished product from strippant. Note that uranium de-sorption from saturated anion exchange resin is done by sulphuric acid solution with concentration 70-100 g/l with the presence of 1-2 mole/l of ammonia sulphate.

EFFECT: decrease of sulphuric acid content in desorbing solution and rich eluate and reduction of sulphuric acid consumption, decrease of desorbing solution flow and anion exchange resin ratio at de-sorption, increase of uranium content in rich eluate at decrease of rich eluate volume and decrease of uranium residual content by 1-2 levels in anion exchange resin after de-sorption.

1 tbl, 3 ex, 2 dwg

 

The invention relates to hydrometallurgy, in particular to a method of extracting uranium from sulfuric acid solutions and slurries.

When sorption processing sulphate productive solutions leaching of uranium the most economical way desorption of uranium from saturated anion exchange resin is a desorption solution of sulfuric acid /1/.

The advantage of sulfuric acid desorption is also a smaller environmental impact on the environment compared to methods that use nitrosoureas solutions.

Despite this, the use of sulfuric acid desorption is constrained by the need for the use of sulphuric acid solutions of high concentration (150-200 g/l), ensures a sufficient degree of desorption of uranium from anion exchange resin (low residual capacity of uranium in the anion) when economically justified the ratio of threads Stripping solution and the anion exchange resin and the uranium content in the product decorate. A high concentration of sulfuric acid in desorbers solution leads to its increased consumption, increased consumption of alkaline reagent to neutralize commodity decorate, and also having use as a structural material is scarce and expensive corrosion-resistant high-alloy stainless steel.

The closest adopted for the prototype, is a JV is the property of ion exchange extraction of uranium from sulphuric acid solutions and slurries, includes sorption of uranium anion exchange resin, the desorption of uranium, production of finished goods from decorate, where the Stripping solution using a solution of sulfuric acid concentration of 15-18%. /Owinnero. "Ion exchangers and ion exchange. Sorption technology in the extraction of uranium and other metals by the method of underground leaching". M., 2007, LLC Unicornscan". - 480, str-281/.

The disadvantage of the prototype method is the high content of sulfuric acid in desorbers solution and product decorate), high residual uranium content in the resin after desorption and great value flows Stripping solution and the anion exchange resin.

The technical result of the invention is to increase the concentration of uranium in the product decorate, reducing the flow ratio Stripping solution and the anion exchange resin, reducing the residual content of uranium in the anion exchange resin after desorption at simultaneous reduction of the content of sulfuric acid in desorbers solution.

The technical result is achieved by the method of ion-exchange extraction of uranium from sulphuric acid solutions and slurries comprising the sorption of uranium anion exchange resin, the desorption of uranium sulfuric acid, the receipt of finished goods from decorate, desorption of uranium from the saturated anion exchange resin are sulfuric acid concentration of 70-100 g/l in the presence of 1-2 mol/if the R of ammonium sulfate.

When the ammonium sulfate in the circulating desorbers solution is formed by the neutralization of commodity decorate before deposition of a commercial product. I.e. more of its introduction in deformirujuschij solution is not required.

Reducing the acidity of the Stripping solution leads to a decrease in the consumption of sulphuric acid consumption of alkaline reagent to neutralize.

The increase in the content of uranium in the product decorate (reduction of flow ratio Stripping solution and anion-exchange) leads to the reduction of costs for the deposition of a commercial product (the decrease in the volume of equipment, reagent consumption and so on).

The use of such sulfate-sulfuric acid Stripping solution will be used as a structural material sparingly alloyed stainless steel.

Example 1

Desorption of uranium solutions of sulfuric acid and sulfuric acid in the presence of ammonium sulfate were carried out in dynamic conditions in the sorption columns with a height of 500 mm, the volume of the anion exchange resin in 30 ml Deformirujuschij the solution was applied from the bottom of the column by a peristaltic pump with a flow rate of 1 volume of solution per volume of resin per hour for 10 hours.

The uranium content in the saturated ion-exchange resin was 49 kg/so the prototype - 40 kg/so

Figure 1 shows the output curves of desorption of uranium from the anion exchanger AMP solutions chamois is th acid in various concentrations in the presence of 1.5 mol/liter of ammonium sulfate.

Table 1 shows the technological parameters of desorption of uranium from the anion exchanger AMP on the prototype method and the proposed method.

Table 1
Technological parameters of desorption of uranium from the resin solutions of sulfuric acid and sulfuric acid in the presence of ammonium sulfate
The content in desorbers solutionResidual sod. U in the anion exchanger, kg/tThe ratio of flows des. R-RA and anion, V/VThe content of U in decorate, g/l
H2SO4, g/lSO42-mol/l
Prototype
150-180-1.5 to 2.53-45-7
By the present method
571,50,665,04
711,5 0,252,87
871,50,032,39
1001,50,012,010
1001,00,022,87

As can be seen from figure 1 and table 1, the addition of 1.5 mol/liter of ammonium sulfate in a sulfuric acid concentration of 71 g/l can get the same output commodity decorate, as in the prototype - 3 V/V of the anion, and the same content of uranium in the product decorate. However, the residual uranium content in the anion exchange resin in our case (0.25 kg/t) lower than the prototype. By increasing the concentration of sulfuric acid in desorbers solution to 100 g/l leads to a decrease in the flow of commodity decorate to 2 V/V of the anion and the reduction of residual uranium content in the resin is still on the order of 0.01 kg/so

Add a solution of 1.0 mol/liter of ammonium sulfate also can get the same output commodity decorate, as in the prototype, but when the concentration of sulfuric acid 100 g/is. The residual uranium content in the resin is 0.02 kg/t, which is 2 orders of magnitude less than for desorption of the prototype.

Example 2

In deformirujuschij solution of sulfuric acid concentration of 100 g/l was added 1.0 and 1.5 mol/l of ammonium sulfate.

Figure 2 shows the output curves of desorption of uranium from these solutions and a solution of pure sulfuric acid concentration of 100 g/l

Table 1 shows the technological parameters of desorption of uranium from the anion exchanger AMP on the prototype method and the proposed method.

Add a solution of 1.0 mol/liter of ammonium sulfate also can get the same output commodity decorate, as in the prototype, but when the concentration of sulfuric acid 100 g/l Residual uranium content in the resin is 0.02 kg/t, which is 2 orders of magnitude less than for desorption of the prototype.

It is clear that further reduction of the content of ammonium sulfate in desorbers solution will lead to the need for the increase of the concentration of sulfuric acid to values close to the values of the prototype.

The increase in salt content of ammonium sulfate in desorbers solution more than 2.0 mol/liter is not technologically justified (economically)because it will lead to unnecessary additional expense sulfate.

Example 3

In deformirujuschij solution of sulfuric acid concentration of 100 g/l was added to 1.0 the ol/l of ammonium sulfate and 1.0 mol/l of sodium sulfate.

Figure 2 shows the output curves of desorption of uranium from these solutions and a solution of pure sulfuric acid concentration of 100 g/l

Add a solution of 1.0 mol/liter of sodium sulfate practically does not improve desorption of uranium from the anion compared to the desorption of pure sulphuric acid.

Thus, for the intensification of the process of desorption of uranium needed not just a sulfate ion, but the ammonium sulfate. Probably ammonium ion shifts the balance between sulfate and bisulfate-ion in desorbers solution towards bisulfate, and the bisulfate ion is a stronger desorbent uranium than sulfate.

Thus, compared with the prototype of the proposed method allows to:

- To reduce the content of sulfuric acid in desorbers solution and product decorate and to reduce the consumption of sulphuric acid.

- Reduce the ratio of threads Stripping solution and the anion on desorption.

- To increase the uranium content in the product decorate for reducing the volume of commodity decorate.

- Reduce by 1-2 orders of the residual uranium content in the resin after desorption.

The method of ion-exchange extraction of uranium from sulphuric acid solutions and slurries, including sorption of uranium anion exchange resin, the desorption of uranium from the saturated anion exchange resin with sulfuric acid and production of finished products from decorate, characterized in that the desorption of uranium from the saturated anion exchange resin are sulfuric acid concentration of 70-100 g/l in the presence of 1-2 mol/l of ammonium sulfate.



 

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1 ex

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1 ex

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9 dwg, 3 tbl, 4 ex

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