SU1227704A1 - Method of separating cobalt and nickel from acid solutions - Google Patents

Description

one .

This invention relates to cobalt and nickel hydrometallurgy and can be used for the extraction of cobalt from weakly acidic nickel-containing solutions, for example, from nickel electrolytes, as well as from nickel-cobalt autoclave leaching solutions.

The purpose of the invention is to increase the selectivity of the separation process.

Example 1. From sulfate solutions having a pH of 3.6 and containing 5.1 g / l of cobalt (II) and 10.01 g / l of nickel (II), the metals are extracted. As an extractant, a 0.37 M solution of di (isooct 1) phosphonic acid (DAFC) in kerosene with the addition of 0.8 M isooctanol, as well as mixtures containing 0.37 M DAFC and trioctylphosphinoxy (TFO), are used at various molar ratios .

The obtained experimental data are given in table. one.

The data obtained show that the best results can be achieved at molar ratios of dialkylphosphinic acid and trialkylphosphine oxide, equal to (10-3): 1.

PR and M e p 2. Extraction are from the original sulfate solution containing 4.9 g / l of cobalt (II) and 10.2 g / l of nickel (II). The time of mixing of the phases during extraction is 1 min, the temperature is 21 C. The extractant is a 0.35 M solution of DAFC in kerosene with the addition of 0.8 M isooctanol, and a mixture of 0.35 M DAFA and 0.07 POFO in kerosene.

In tab. 2 shows the data on the extraction of cobalt and nickel at various pH values of the equilibrium aqueous phase.

As can be seen from the obtained data, the use of the extractant of the proposed composition allows to increase the selectivity of cobalt extraction and makes it possible to extract from more acidic solutions, which reduces the consumption of reagents, such as ammonia, to neutralize the aqueous phase.

P and M a p 3. Carry out the extraction of cobalt from nickel-containing sulphate solutions at pH 3.5 with a 0.35 M solution of DAFC in kerosene with a 0.8 M isooctanol or ne277042 solution.

, organic phosphorus reagent: 0.05 M tributyl phosphate (TBP); 0.05 M di (isooctyl) methylphosphonate (DAMP); 0.05 M TOPO. Ratio

5 volumes of phases during extraction, temperature 23 ° C. The composition of the aqueous phase is 1.03 g / l of cobalt (11) and 35.6 g / l of nickel (II).

The experimental data presented in Table. 3 show. That an increase in the selectivity of the process and the capacity of the extractant for cobalt is achieved only when using trioxylphosphine 13 as a modifier.

PRI and MER 4. Extraction of metals with alkylphosphonic acid is carried out from sulfate solutions at an equilibrium pH of the aqueous phase of 3.2. Composition

20 original aqueous solution, g / l: cobalt 5.0; nickel is 10.2 and iron is 1.2. The ratio of the volumes of the phases during extraction, temperature 21 C. The data on the composition of the equilibrium organic and aqueous phases are given in Table. four.

From the data obtained, it can be seen that the introduction of trialkylphosphine oxide into the extractant increases the selectivity of the extraction process not only for nickel (II), but also for iron (II).

EXAMPLE 5 Cobalt was extracted from a sulphate solution in a countercurrent mode using a mixture of 0.36 M DAFC and 0.06 M TOPO in kerosene as the extractant. The composition of the initial sulfate aqueous solution is 1.3 g / l of cobalt (II) and 38.9 g / l (II). Extraction is carried out in 4 steps of countercurrent with the ratio of the volumes of aqueous and organic phases, temperature and pH value of the equilibrium aqueous phase of 3.5. After extraction, the saturated organic phase is washed with an aqueous solution containing 20 g / l of cobalt (II) at a pH of 3.0 and a ratio. Then re-extraction is carried out with an aqueous solution containing 50 g / l of sulfuric acid, with a ratio. The result is a reextract containing 19.2 g / l of cobalt (II) and 0.11 g / l of nickel (II). Thus, the ratio of cobalt: nickel increases by 5220 times. Extraction of cobalt from the initial aqueous solution is 98.7%.

35

40

3

EXAMPLE 6 An extraction process is carried out as in Example 5, but a solution in kerosene of 0.36 M DAFC with the addition of 0.8 M isooctanol is used as the organic phase. The result is a reextract containing 12.4 g / l of cobalt and 0.26 g / l of nickel. This corresponds to an increase in the ratio of cobalt: nickel concentrations by 1420 times. Extraction of cobalt from the original aqueous solution amounts to 95.2%. I

Thus, the proposed method for the separation of cobalt and nickel improves the selectivity of the extraction process, increases the capacity of the extractant for cobalt and reduces the consumption of reagents for neutralizing the aqueous phase due to

0.37: 0 (1: 0) 34, i

0.37: 0.036

The separation factor is calculated as the ratio of the distribution coefficients of cobalt and nickel.

27704 4

the ability to carry out the extraction process from more acidic solutions. As a result, the extraction of cobalt is increased, and commercial production of metallic cobalt, cobalt sulfate or cobalt hydroxide can be obtained by 6ojjee of high quality.

For the basic principles of technology,

to based on the separation of cobalt and nickel by the extraction of di-2-ethylhexylphosphoric acid. Compared with this technology, the proposed method allows increasing the output of kt5 balt in the form of commercial products by 3.5% and reducing the consumption of reagents for the neutralization of the aqueous phase by 10- 15%. With a capacity of 300 tons of cobalt per year, the magnitude of the eco-economic effect will be 244650 r.

Table 1

0.49

0.535

0,005

107

Concentration in the aqueous phase, g / l cobalt

nickel

Concentration in the organic phase, g / l

cobalt

nickel cobalt distribution coefficient nickel distribution coefficient

Split ratio, / O CcffJi

table 2

Table 3

0,260.19

35,035,6

0.780.93

0.640.18

3,08,5

0,0180,005

i67

167

700

4.10 10.1 0.85

0.95 0.03 0.4

18.9 0.3 33.4

Compiled by L.R. Kin Editor M.Dshin Tehred M.MorgentalKorrektor M.Samborska

"

Order 2266/29 Circulation 567 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Table 4

3, J610,30,97

1,310,020,2

26,20,2

16.8

Claims (1)

METHOD FOR SEPARATING COBALT AND NICKEL FROM ACIDIC SOLUTIONS, including extraction of cobalt with an organic extractant solution containing phosphinic acid, a modifier and a diluent, characterized in that, in order to increase the selectivity of the separation process, trialkylphosphine oxide is used as a modifier and the extraction is carried out at a ratio of phosphine trialkylphosphine oxides equal to (3-10): 1.