SU1214774A1 - Method of removing cobalt and nickel from zinc solutions - Google Patents

Description

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The invention relates to non-ferrous metallurgy, in particular to the hydrometallurgical method for producing zinc.

The aim of the invention is to increase the degree of purification of the solutions, reducing the consumption of reagents.

Example 1 To carry out experiments on the purification of solutions from cobalt and nickel, a solution of the following composition was taken: zinc 120 g / l; cobalt 112 mg / l; nickel 50 mg / l and cadmium 30 mg / l.

The solution was poured into an electrolyzer equipped with a mechanical stirrer with a lead-silver anode and an aluminum cathode, heated to a temperature of 55-60 ° С, antimony concentrate of the following composition was filled,%: Antimony 41.9; tin 0.65; lead 1.7; blink to 1.52, and asked a solution of copper sulphate,

Then the current was turned on and zinc dust was removed in two steps.

The results of experiments on the effect of expenditure ratios on the degree of purification are summarized in Table 1.

The data in Table 1 show that with the consumption of zinc dust 2.3; 2.5; 3.0 and 3.5 g / l, the degree of purification of the solution from cobalt and nchkel is equally high (98.4 and 97.6%, respectively). On this basis, the consumption of zinc dust was 2.3-2.5 g / l, since a further increase in the consumption of the zinc core is impractical.

The results of the influence of current density on the degree of purification from cobalt and nickel are presented in Table 2.

Experimental conditions: V solution 0.7; temperature 55-60 ° C; time 2 hours. Content in the initial solution, mg / l: CO 112; Ni 50.

It follows from Table 2 that the optimum cathode current density is 700-1000 A / m, while increasing the current density, acidification of the solution and dissolution of part of the zinc dust are observed, which is negatively affected by the removal of cobalt from the solutions.

Example 2: To compare the proposed method for the purification of zinc solutions and the prototype method, laboratory experiments were carried out

1 l of solution containing 100 mg / l of cobalt and 125 mg / l of nickname 14774 2

l, poured into a vessel with mechanical agitation, heated to 80 ° C and cementation of cobalt and nickel was performed with the consumption of zinc dust

5 9 g, antimony concentrate, 0.245 g, and copper, 0.5 g. After the end of loading, the pulp was stirred for 30 min and filtered.

The compositions of cement sediments and purified solutions of the prototype are presented in Table 3.

Experimental conditions: V of solution 1 l, temperature 80 С, content in the initial solution, mg / l: Co 92.3;

5 Ni 54.8.

From the data of Table 3 it follows that the purification of solutions from cobalt occurs only when the content of cadmium is at least 1 g / l. Sediment yield with

20 1 l of the solution is 15 g. The content of cadmium is 6-11%. Precipitates with this content of cadmium must be recycled in order to extract it.

25 According to the proposed method, the sediment yield is 5-6 g / l, and the cadmium content in it does not exceed 0.4%. This result is achieved due to the application of an electric current during cobalt cementation, i.e. in this case there is no need to have in the original solution

high concentration of cadmium with a good degree of cleaning solution from cobalt and nickel.

The compositions of cement sediments and purified solutions according to the proposed method are given in Table 4 (initial solution, mg / l: Co 92.3; Ni 54.8X

It follows from the table that for the purification of solutions from cobalt and nickel, the presence of cadmium in the initial solution is not a necessary condition. A much smaller sediment yield during the purification of cobalt (as compared with the prototype) and a low content of cadmium in the sediment facilitate its processing.

The precipitate can be immediately sent to the Waelz process to extract 50 zinc and cadmium, or more easily processed to extract cobalt and nickel.

The use of the proposed method will allow in comparison with the prototype to reduce the loss of zinc dust on the redistribution of cleaning zinc solutions from cobalt by 4.9% and cadmium by 1.5%.

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Table 1

Table 2

Claims (1)

METHOD FOR CLEANING ZINC SOLUTIONS FROM COBALT AND NICKEL, including treatment of solutions with zinc dust in the presence of antimony concentrate and copper ions, characterized in that, in order to increase the degree of purification of solutions, reduce the consumption of reagents, cementation of cobalt and nickel is carried out by applying an electric current with cathode density 700-1000 A / m ^g , zinc dust consumption 2.3-2.5 g / l, antimony concentrate 100-200 mg / l and copper ions 100-200 mg / l. _with "o