JPH0681050A - Method for recovering nickel and cobalt - Google Patents

Abstract

PURPOSE:To preferentially precipitate and recover Ni and Co at high yields by adding an alkali sulfide compd. to an acid soln. obtd. by leaching Ni- and Co-contg. raw materials with a mineral acid to precipitate and form the Ni and Co as sulfides. CONSTITUTION:The ore oxide, waste media and other raw materials in which the Ni and Co coexist are treated with the mineral acids, such as sulfuric acid, hydrochloric acid and nitric acid, to prepare an acid aq. soln. of pH >1.5 in which the Ni and Co or further, simultaneously contained components, such as Fe, Al, Mn, Mg and Cr, are acid-leached. After this aq. acid soln. is heated to and held at <=100 deg.C, the alkali sulfide compd., such as sodium sulfide or sodium hydrosulfide, is added thereto at 1.1 to 1.3 times the theoretical equiv. for formation of NiS and CoS to effect reaction for 5 to 60 minutes. The Ni and Co are preferentially deposited and precipitated as NiS and CoS and are filtered. The Ni and Co are thus recovered in the form of the sulfides at the good yields.

Description

Detailed Description of the Invention

[0001]

The present invention relates to nickel, cobalt,
Or, it contains nickel or cobalt obtained by acid leaching oxide ore, manganese nodule, cobalt crust, waste catalyst, Ni, Co alloy scrap, etc. in which nickel and cobalt coexist, or else iron, aluminum, manganese ,
The present invention relates to a method for preferentially and efficiently recovering nickel and cobalt as sulfides from an acidic aqueous solution containing magnesium, chromium and the like.

[0002]

2. Description of the Related Art As a method for recovering sulfides from an acidic aqueous solution containing nickel and cobalt, hydrogen sulfide gas is used as described in page 700 of the Metal Smelting Technology Handbook (publishing office, Asakura Shoten). Sulfurization is performed using an autoclave under a pressure of ^{2 to} 10 kg / cm ² and at a high temperature of 100 ° C. or higher.

In the autoclave operation under such conditions, the sulfide adheres to the tube wall of the autoclave, and it is often necessary to stop and remove the operation.

Further, since hydrogen sulfide gas reacts with an acidic aqueous solution containing nickel and cobalt, a large amount of seed crystals are produced in order to produce a sulfide having a low rate of sulfide formation and good filterability and separability. Since it is necessary to allow sulfides to exist in advance, the device becomes large.

As an improvement of this technique, Japanese Examined Patent Publication No. 60-543
Japanese Patent No. 78 discloses a method using metallic iron as a catalyst and Japanese Patent Publication No. 61-
Japanese Patent No. 28731 discloses a technique in which copper is used as a catalyst to generate a sulfide at atmospheric pressure, but in any case, since the hydrogen sulfide gas used is a highly poisonous gas, it is difficult to handle in many cases, and the device is also used. There is the problem of complication.

[0006]

The problem to be solved by the present invention is that nickel and cobalt are used as sulfides from an aqueous solution which may contain iron, aluminum, manganese, magnesium, chromium and the like in addition to nickel and cobalt. Upon selective recovery, sodium hydrosulfide, sodium sulfide, or a mixture of sodium hydrosulfide and sodium sulfide is reacted with nickel, cobalt, or an acidic aqueous solution containing nickel and cobalt at 100 ° C. under normal pressure.
It is to produce nickel sulfides and cobalt sulfides at the following temperatures in a short time without using an autoclave, with good efficiency and good filterability.

[0007]

According to the present invention, when recovering nickel and cobalt from nickel, cobalt, or an acidic aqueous solution containing nickel and cobalt, sodium hydrosulfide, sodium sulfide, or a mixture of sodium hydrosulfide and sodium sulfide is used. Provided is an efficient method for recovering nickel sulfide and cobalt sulfide by reacting an aqueous solution containing nickel and cobalt at a temperature of 100 ° C. or less at atmospheric pressure and a pH of an acidic aqueous solution in a range of 1.5 or more. To do.

The present invention will be described in detail below.

An acidic aqueous solution containing nickel, cobalt, or nickel and cobalt was kept at 100 ° C. or lower to react with sodium hydrosulfide, sodium sulfide, or a mixture of sodium hydrosulfide and sodium sulfide.

When the reaction temperature is 40 ° C. or lower, the reaction rate of the sulfide is slow and it takes a long time to form the sulfide, which not only lowers the recovery rate of nickel and cobalt but also reduces the particle size of the sulfide, resulting in filtration and separation. Becomes worse.

On the other hand, a higher temperature is more preferable, but from the viewpoint of economy and equipment, the temperature is set to 100 ° C. or lower, and the reaction is considerably accelerated at 50 ° C. or higher, and the reaction speed of sulfide is sufficiently high at 80 ° C. Sulfide having a large diameter is generated, and the filter separation property is improved.

From the above, the reaction temperature is 100 ° C. or lower, preferably 60 to 80 ° C. A reaction time of about 5 to 60 minutes is usually sufficient.

It is desirable that the acidic aqueous solution PH during the reaction is adjusted to a range of 1.5 or more. PH is 1.5
If it is less than the above, the recovery rate of nickel and cobalt decreases.

The reaction pressure was atmospheric pressure. It may be carried out under pressure using an autoclave, but there is no difference in terms of reactivity and formation of sulfides, and it is not necessary. The reaction atmosphere is preferably reducing.

However, even in the reducing atmosphere, it is not necessary to replace it with hydrogen sulfide gas or hydrogen gas, and it is sufficient to prevent the invasion of air.

The amounts of sodium hydrosulfide and sodium sulfide used are 1.1 to 1 which is the theoretical equivalent amount required to produce nickel and cobalt in the acidic aqueous solution as nickel sulfide (NiS) and cobalt sulfide (CoS). 3 times is enough.
If it is less than 1.1 equivalents, the recovery rate of nickel and cobalt decreases.

On the other hand, at 1.3 equivalents, the recovery rate of nickel and cobalt is 99%, and there is no economic merit if more than this is used.

Although sodium hydrosulfide and sodium sulfide are used as an aqueous solution, there is no problem even if they are used as a solid.

Hereinafter, the present invention will be described in more detail with reference to Examples.

[0020]

Example 1 Ni obtained by pressure leaching of an oxide ore containing nickel and cobalt with sulfuric acid under pressure of Ni = 2.65 g /
1, Co = 0.17 g / l, Fe = 0.10 g / l, A
l = 0.25 g / l, Mn = 1.86 g / l, Mg =
An acidic solution of 1.82 g / l and Cr = 0.06 g / l was maintained at a temperature of 80 ° C. in the reaction vessel, and Ni and Co in the solution were added in an amount of 1 necessary for producing NiS and CoS as sulfides. A 3-fold equivalent of 25% sodium hydrosulfide solution was added and stirred.

The liquid concentration was analyzed 2, 5, 10, 20, 30 minutes after the addition, and the recovery rate of Ni and Co as sulfides was determined. After 30 minutes, the sulfide and the liquid were separated by filtration, and the component and particle size of the sulfide were examined.

As a result, 99% of Ni and Co could be recovered as sulfides 5 minutes after the addition of sodium hydrosulfide. The liquid pH at that time was 2.8. Table 1 shows the results of the recovery rates of Ni and Co as sulfides.

The sulfide component is Ni = 45.7%, Co
= 2.90%, S = 32%, Fe = 0.08%, Al =
0.10%, Mn = 0.15%, Mg = 0.18%, and Ni and Co were selectively recovered as sulfides. The average particle size was 28μ, and the filter separation property was very good.

[0024]

Example 2 Example 1 except that the reaction temperature was 60 ° C.
The same conditions were used. The results are shown in Table 1. 20 minutes after the addition of sodium hydrosulfide, 98% of Ni and Co could be recovered as sulfides. The liquid pH at that time was 2.5, and the average particle size was 25 μ.

[0025]

Example 3 Example 1 except that the reaction temperature was 40 ° C.
The same conditions were used. The results are shown in Table 1. Even after reacting for 30 minutes after adding sodium hydrosulfide, Ni, C
The recovery rate of o as sulfide decreased to 88% and 73%,
The average particle size was also reduced to 15μ, and the liquid PH was 2.5.

[0026]

[Example 4] The same conditions as in Example 1 were carried out except that the amount of sodium hydrosulfide added was 1.1 equivalents. The results are shown in Table 1. Even after reacting for 30 minutes after the addition of sodium hydrosulfide, the recovery rates of Ni and Co as sulfides were 87% and 79%, respectively, and the average particle size was 28μ. The liquid pH at that time was 2.7.

[0027]

Example 5 Ni = 10.24 g / l, Co = 0.70
g / l, Fe = 0.21 g / l, Al = 0.18 g /
1, Mn = 0.26 g / l, Mg = 13.7 g / l, C
The same conditions as in Example 1 were used except that an acidic solution of r = 0.08 g / l was used. Five minutes after the addition of sodium hydrosulfide, 99% of Ni and Co could be recovered as sulfides. The average particle size was as large as 30 μm and the filter separation property was very good. The liquid pH at that time was 1.9.

[0028]

[Example 6] The same conditions as in Example 1 were carried out except that sodium sulfide was used instead of sodium hydrosulfide, and the addition amount of sodium sulfide was 1.3 equivalents. 98% of Ni and Co could be recovered as sulfides 10 minutes after the addition of sodium sulfide. The average particle size was as large as 27 μm, and the filter separation property was very good. The liquid pH at that time was 3.5.

[0029]

Example 7 Except that sodium hydrosulfide and sodium sulfide were mixed and used at an equivalent ratio of 1: 1 in terms of S.
The same conditions as in Example 1 were used. 99 minutes after addition of the mixture of sodium hydrosulfide and sodium sulfide,
% Could be recovered as sulfide. The average particle size was as large as 28 μ, and the filter separation property was very good. The liquid pH at that time was 3.1.

[0030]

Example 8 Ni = 3.72 g / l, C obtained by pressure leaching a spent catalyst containing nickel and cobalt with sulfuric acid.
o = 1.65 g / l, Fe = 0.07 g / l, Al =
1.53 g / l, Mn = 0.03 g / l, Mg = 1.1
A 1 g / l acidic solution and 1.3 equivalents of sodium hydrosulfide were added to Ni and Co and reacted at 80 ° C. for 10 minutes. N
99% of i and Co could be recovered as a sulfide, the average particle size was as large as 28μ, and the filtration separation property was very good. The liquid pH at that time was 2.7.

[0031]

Example 9 Manganese nodules were leached with sulfuric acid to obtain Ni = 1.15 g / l and Co = 0.36 g / l.
1, Cu = 0.87 g / l, Fe = 5.03 g / l, A
l = 0.23 g / l, Mn = 25.0 g / l, Mg =
An acidic solution of 0.52 g / l and Cr = 0.11 g / l and 1.2 equivalents of sodium hydrosulfide were added to Ni, Co and Cu and reacted at 80 ° C. for 10 minutes. 98 of Ni and Co
%, And 99% of Cu could be recovered as a sulfide, the average particle size was as large as 31 μ, and the filter separation property was very good. The liquid pH at that time was 3.1.

[0032]

Example 10 Ni = 3.12 g / l, Co = 0.26
g / l, Fe = 0.41 g / l, Al = 0.15 g /
l, Mn = 1.36 g / l, Mg = 13.7 g / l hydrochloric acid solution and sodium hydrosulfide for Ni and Co of 1.25
An equivalent amount was added and the mixture was reacted at 80 ° C. for 10 minutes. 99% of Ni and Co can be recovered as sulfides, and the average particle size is 30μ
And the filterability was very good. The liquid pH at that time was 1.6.

[0033]

Example 11 Ni = 4.32 g / l, Co = 0.37
g / l, Fe = 0.16 g / l, Al = 0.20 g /
l, Mn = 1.55 g / l, Mg = 10.3 g / l nitric acid solution and sodium hydrosulfide 1.30 with respect to Ni and Co
An equivalent amount was added and the mixture was reacted at 80 ° C. for 10 minutes. Ni 97
%, And 99% of Co could be recovered as sulfides, the average particle size was large at 27 μ, and the filter separation property was very good. The liquid pH at that time was 1.7.

[0034]

Example 12 Ni = 7.36 g / l, Co = 2.42
g / l, Fe = 0.40 g / l, Mn = 0.59 g /
1, Cr = 0.74 g / l mixed acid solution of sulfuric acid and nitric acid, and sodium hydrosulfide were added in an amount of 1.25 equivalents to Ni and Co,
The reaction was carried out at 80 ° C for 10 minutes. 98% of Ni, 9 of Co
8% could be recovered as a sulfide, the average particle size was as large as 29μ, and the filterability was very good. The liquid pH at that time was 1.7.

[0035]

Example 13 Ni = 5.50 g / l, Fe = 6.32
g / l, Mn = 0.10 g / l, Cr = 0.12 g / l
1.25 equivalents of the mixed acid solution of sulfuric acid and hydrochloric acid and sodium hydrosulfide were added to Ni and reacted at 80 ° C. for 10 minutes. N
98% of i can be recovered as sulfide and its average particle size is 2
It was as large as 8μ, and the filterability was very good. The liquid pH at that time was 1.6.

[0036]

Example 14 Co = 4.57 g / l, Fe = 5.36
g / l, Mn = 0.08 g / l, Cr = 0.09 g / l
A mixed acid solution of hydrochloric acid and nitric acid and 1.25 equivalent of sodium hydrosulfide were added to Co and reacted at 80 ° C. for 10 minutes. C
99% of o can be recovered as sulfide and its average particle size is 2
It was as large as 8μ, and the filterability was very good. The liquid pH at that time was 1.8.

[0037]

Comparative Example 1 The same acidic solution as in Example 1 was kept in an autoclave at 120 ° C. and a high temperature and high pressure of 2.5 kg / cm ² , and the reaction was carried out by stirring for 60 minutes while blowing hydrogen sulfide gas. The hydrogen sulfide gas was used in an amount of 2.5 equivalents, which was the amount necessary to produce Ni and Co in the solution as NiS and CoS sulfides.

Then, the sulfide and the liquid were separated by filtration, and the recovery ratios of Ni and Co were determined by analyzing the liquid concentration of the filtrate. Sulfide was examined for particle size. As a result, the recovery rate of Ni and Co was 82.
%, And the average particle size of the sulfide was as fine as 13 μm, and the separability by filtration was not good. The liquid PH at this time was 2.3.

[0039]

Comparative Example 2 The same acidic solution as in Example 1 was reacted in an autoclave at 80 ° C. under the condition of 1 kg / cm ² for 60 minutes while blowing hydrogen sulfide gas. The amount of hydrogen sulfide gas used was 2.5 equivalents of Ni and Co.
At this time, the recovery rates of Ni and Co were 66%, and the average particle size of the sulfide was 10 μ. The liquid PH was 2.6.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

According to the method of the present invention, nickel sulfide and cobalt sulfide can be produced more easily and safely than ever before from nickel or cobalt, or an acidic aqueous solution in which nickel and cobalt coexist. Is simplified.

[Brief description of drawings]

FIG. 1 is a diagram showing changes in reaction time, (a) Ni recovery rate, and (b) Co recovery rate when the addition equivalent of sodium hydrosulfide is set to 1.3.

FIG. 2 is a diagram showing changes in addition equivalent of sodium hydrosulfide, Ni recovery rate, and Co recovery rate when the reaction temperature is 80 ° C. and the reaction time is 30 minutes.

FIG. 3 is a diagram showing a relationship between a reaction temperature and an average particle diameter of sulfide.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masashi Izumimoto Aoyama Prefecture, Odaira, Kawara Wood, Toyama Nitta (no address), Odaira Metals Co., Ltd., Hachinohe Factory (72) Inventor, Ryuzo Wakamatsu, Aomori, Kawaragi Toyama Nitta (no address) Ohira Yohkin Co., Ltd. Hachinohe Factory

Claims (5)

[Claims] 1. A method for recovering nickel and cobalt in which nickel and cobalt or an acidic aqueous solution containing nickel and cobalt are reacted with an alkali sulfide compound to precipitate nickel and cobalt as nickel sulfide and cobalt sulfide, respectively. Is less than 100 ° C under normal pressure, and is recovered as nickel sulfide or cobalt sulfide having good filtration and separation properties. 2. The method according to claim 1, wherein the pH of the acidic aqueous solution is 1.5 or more. 3. The method according to claim 1, which comprises reacting the acidic aqueous solution with sodium sulfide or sodium hydrosulfide. 4. The method according to claim 1, which comprises reacting the acidic aqueous solution with a mixture of sodium hydrosulfide and sodium sulfide. 5. The acidic aqueous solution is an aqueous solution containing sulfuric acid, hydrochloric acid, a nitric acid solution or a mixed acid of two or more kinds thereof.
The method described.