DE2009905C - Process for separating nickel - Google Patents

Description

ι 2

The invention relates to a method for a nickel product can be obtained in the Separation of nickel, of cobalt, and, if it is essentially free of cobalt, is such a thing on hand, of iron, where reducible nickel processes have not yet been developed,

and cobalt compounds by heating in a re-The nickel and cobalt materials are carbonylated

reducing atmosphere to a temperature of 5, and the carbonyls obtained were separated,

less than 400 ° C can be reduced to metal and the starting materials in some cases are metal-

obtained metal product at a temperature of the products obtained by reduction processes.

less than 100 ° C carbonylated and the nickel car- was made,

bonyl is separated from the cobalt. Such a method is e.g. B. in “The Mining

The method of the invention is described for the treatment of "io Journal", December 7, 1962, p. 453,

Nickel-containing oxidic materials suitable and ins- It has now been found that solutions containing nickel

special for hydrometallurgical and steam metal and cobalt contain, to separate the nickel from

lurgical treatment of nickel-containing oxide ores, which can be treated by making cobalt

to the resulting nickel as essentially pure nickel carbonyl from this solution the reducible nickel and co-

to win. 15 connections fail, the connections at

Under the term "nickel special conditions reduced and the reduced containing lateritic ores" or "nickel-containing compounds steam-metallurgically treated to oxidic ores" are used to produce the weathered products of nickel-carbonyl. Olivine and serpentine are understood. These ores The process of the present invention can therefore be concentrated by the usual procedures, such as by the ao characterized in that the reducible flotation or by magnetic separation, non-metal compounds from an aqueous solution without further concentration, so that the ge. falls and separates and, in the case of superatmospheric all mined ore, is carbonylated to less than 15 atmospheres to obtain the nickel. must be acted on. The inability to concentrate these ores containing nickel and cobalt has made the separation of the nickel and aqueous solution quite difficult to deal with, to make the nickel, and sometimes cobalt, quite difficult. Separate cobalt from it and extract it. The So are, for example, to melt this aqueous solution is treated so that the nickel ore to produce ferronickel or nickel stone, and the cobalt content of the solution as reducible large amounts of fuel is required to fill the bonds of these metals, the to melt the entire ore, but only 1 or 2% 3o reducible compounds after separation and the valuable part of the ore can be obtained. Drying are by heating to a temperature of Weni-Other disadvantages of this method is that ger than 400 ⁰ C, generally of more than 20O ⁰ C, no effective means for the separation of nickel a reducing atmosphere, reduction pieces in it to the metal and cobalt provide. In fact, the cobalt often goes to be graced. The nickel and cobalt are then lost when cleaning the ferro-nickel or 35 separately by attempting the reduced compounds with the nickel stone. superatmospheric partial pressure of carbon monoxide

Nickel is also already made from lateritic ores by less than 15 atmospheres at temperatures of

hydrometallurgical process has been obtained. So less than 100 ⁰ C carbonylated and thereby gaseous

in Cuba, for example, nickel-containing nickel carbonyl is formed, which is derived from the reducing

Limonite ore (with a high iron content) is released directly with Schwe- 40ten material, while the cobalt there-

fic acid leached, which is left behind for separate extraction at elevated temperatures,

doors and suitable pressures that the amount of the reduction at temperatures of 400 ⁰ C and the

loosened iron is limited. Although this process takes place at temperatures less than carbonylation

goes reasonably well, but it can only be 100 ° C z. B. from pages 67 and 68 of the textbook

find application to limonitic ores, since ores with 45 der Metallhüttenkunde from V. Tafel, 2nd edition,

lower iron contents larger amounts of Magne- 1954, known.

have sium, which reacts with the sulfuric acid, According to a special embodiment of the

which greatly increases the amount of acid required. Finding a process for the extraction of nickel

will. The raw nickel-cobalt is then a special and cobalt from lateritic ores, the nickel, cobalt

len refined to contain the nickel from the so and iron, which provided

Separate cobalt. C a r ο η already earlier consists in the fact that the lateritic ore can be selectively Teaching given that nickel-containing oxide ores selectively reduced to a predominant part of the nickel

reduced and with an ammoniacal ammonium and cobalt and only controlled amounts of the

Umcarbonatlösung could be leached. To reduce from iron that one reduced that selectively

the solution is nickel together with cobalt ore with an ammoniacal ammonium carbonate

obtained by heating the solution to leach ammonia solution with aeration to make a leaching solution

and to distill off carbon dioxide and to form the basic solution of nickel and cobalt, which is only

Precipitate carbonates of nickel and cobalt. contains small amounts of iron that one can When carrying out the above-mentioned caustic solution, ammonia and carbon dioxide are distilled off on an industrial scale, Process, the cobalt content in the final 60 µm basic carbonates of nickel, cobalt and egg Nickel protuct is actually limited and to precipitate within the senses that the basic carbonates are in

More accurate specifications are kept by going to a reducing atmosphere at a temperature

The degree of reduction is visibly limited, which, however ^{, is reduced by below about 375 °} C. to a reduced one

to form an adverse effect on the extraction of the metal product and to have that reduced

Nickel is connected. Although attempts have already been made

have been established, an extraction process for partial pressure of Noxyd of less than about 15 atmospheres

to make a multitude of lateriti- spheres at a temperature of less than about

see Firzen can be treated and treated at 100 ° C to nickel and iron carbonyls

to image that is derived from that in the reduced metal pro- neither sulfidic (roasted or unroasted) or

The remaining cobalt can be separated from the product. oxidic ores are leached. Although the

According to a further embodiment of the experience according to the present invention,

Finding is a process for the extraction of nickel which can be used to convert nickel from iron in such

from lateritic ores containing nickel, cobalt and more 5 materials such as nickel containing oxidic

containing more than about 40 / o iron, ores, e.g. B. lateritic ores containing nickel,

that then consists of separating the lateritic ore at, the leaching takes place more often-

Temperatures between about 230 and 260 ° C in a white so that inadmissible amounts of iron are not in.

Autoclave leached with sulfuric acid to be taken to an aqueous solution. This is therefore advantageous

nge sulphate solution, the nickel, cobalt and only limited io due, because the dissolution of the iron the use of

Contains te amounts of iron to produce that one requires this additional and often expensive chemicals

Sulphate solution a precipitating agent from the group of and precipitation of iron often creates difficulties

Bases and the water-soluble carbonates are added to the handling of the materials, namely in

reducible compounds of nickel, cobalt and form of difficulties in filtration with them

Precipitating iron so that the reducible ones can be brought. The presence of iron, even in large quantities

Bonds separates from the aqueous solution, that amounts, however, impairs the feasibility

d: e separated reducible compounds in one of the process according to the present invention

reducing atmosphere at a temperature below- not. When carrying out the procedure according to

half about 375 C reduced to a reduced metal- present invention is part of any re-

product, and that the reduced me- ao duced iron together with the nickel carbony-

The metal product is monoxidized with superatmospheric carbon, and the two gaseous carbonyls become

Partial pressures of less than 15 atmospheres and separated from the cobalt-containing residue.

Temperatures below about 100 ⁰ C treated to The gaseous carbonyls are then liquefied

Nickel and iron carbonyls are produced by the and are subjected to distillation, creating a very

in the reduced metal product remaining as pure Nrekel carbonyl, which is essentially iron

Cobalt can be separated. and is naturally free of cobalt.

The process of the invention is particularly useful for treating nickel-containing oxide ores, the selection of the leaching operation depends on the treatment of nickel-containing oxide ores. The leaching that is either basic or the nature of the ore depends. So z. B. nickel can be de-acidified, can be done so that 30 holding lateritic ores, the more than 45 ° / ₀ iron the extraction of nickel and cobalt in one (and therefore only small amounts of magnesium oxide, the level is brought to a maximum value After not exceeding 3 ° / ₀ ) contained, directly with Schweder filtering off the leaching solution and the formic acid at elevated temperatures, e.g. B. 230 to 260 ⁰ C precipitation of nickel and cobalt from it is leached out in an autoclave under suitable pressures 35 to be treated in the pressure device, whereby an aqueous sulfate solution forth material has been significantly reduced, ie, less made The nickel, cobalt and only more than about 4% of the ore are reduced and carbony- limited amounts of iron are contained. The sulphate solution can be lated. Through the leaching, cobalt is also obtained from ore with nickel with a base or a water-soluble carbonate, so that the mass of the reducible hydroxides or ore for cobalt extraction are subsequently no longer treated with basic carbonates of nickel and cobalt needs. Another advantage accruing to the further processing according to the previous method is that even when the present invention is accessible,
lateritic ores containing nickel and cobalt, considerable parts of the iron associated with the ore, are leached out and, together with the nickel and the cobalt which is most advantageously selectively precipitated in such a way, a pure 45 is readily reduced that a predominant part, e.g. B. more than nickel is obtained, which is essentially cobalt 75% of nickel and cobalt and only controlled and iron free. Amounts of iron, e.g. B. no more than 3 parts iron

According to the method according to the present invention, nickel per part can be reduced. The selective redefining can be any nickel-containing solution, ore adorned, is then treated with ammoniacal ammo. However, the process is then leached with aeration on the sodium carbonate solution in order to be most advantageously used when the solution to be dissolved in nickel, cobalt and smaller amounts of iron has a nickel-to-cobalt ratio of sen. The leaching with ammoniacal ammo is less than about 100: 1, since the process can provide a niumcarbonatlösung at temperatures an effective way to separate the nickel from 20 and 90 ⁰ C and at suitable pressures before the cobalt. Likewise, all nickel can be taken from the fact that the distillation of ammo-containing materials with inclusion of nickel-containing niac and carbon dioxide to a minimum value to oxidic ores in which nickel to cobalt ratio is returned. The leaching will advantageously be less than about 100: 1, treated wisely at temperatures between 30 and ^{70 0} C in order to provide solutions containing nickel and cobalt in order to provide the more rapid diffusion of the oxygen necessary for the separation of the nickel from which 60 the rate of nickel oxidation on a cobalt can be treated. To bring the maximum value and to reduce the evaporation

The method according to the present invention rate of ammonia and carbon dioxide

is generally attributed to a minimum value, mostly in connection with a. The basic ones

Leaching is used, but nickel carbonates of nickel and cobalt can also be used

Process solutions are dealt with, which are used by other 65 preparation of the subsequent

Sources like from an electric refinery. be precipitated according to the treatment taking place,

The leaching can be done either with acidic or with removing ammonia and carbon dioxide from the solution

Basic solutions are accomplished if ent- by heating or degassing by vacuum or a

Combination of these measures can be distilled off. can be in concentrated form. If the latter procedure is preferred, since no additional reagents are necessary for the precipitation-reducing atmosphere, then the atmosphere should have a reducing agent and, since the ammonia distilled off, and the carbon dioxide distilled in a CO: COg ratio for further use for 5 of at least 1: 4-10 »is equivalent and that can be recovered prior to the leaching operation is advantageously greater than 1: 10 ² . The reduction nen. Other leaching methods can be used under these temperature and atmospheric conditions. For example, nickel deposits can be selectively reduced at technically attractive speeds, o.iydic ores and, while aerating a highly reactive metal product, leached with acid in order to reduce the amount of iron. According to the if an important aspect of the present Er-Neulralisadon of the leaching liquid, a reduction. Ensuring technically usable nickel-decoratable residue from nickel and cobalt. For the yields, ie 80% or more of nickel yields from at least 80% or more treatment, must be superatmospheric. 15 partial pressures of carbon monoxide, e.g. B. at least

One of the important features of the present er- 2 atmospheres are used. Advantageously, the precipitation of the reducible compound is higher pressures are used, so that larger amounts of solutions are used in the industrial fertilization of nickel and cobalt from aqueous, attractive speeds. Precipitation, especially fresh low nickel, can be obtained. The partial pressure of the shock, which come from liquid solutions, are ao carbon monoxide, but should not exceed 15 atmospheres in chemical terms very reactive. So spheres go beyond, since at these high pressures, for example, precipitates from aqueous selectivity of the carbonylation of nickel in the solution can be reduced at temperatures which begin to decrease considerably to cobalt. Carbon monoxide partial pressures between fertilizers are considerably lower than they are for the same compounds, if these are used according to pyrometallic 6 and 12 atmospheres to produce high nickel-surgical working methods. Since a yield at high reaction rates is another feature of the present invention that can be achieved without undue impairment of the reduction of the nickel and cobalt compounds in the selectivity of the carbonylation. The temperature is usually below 340 ⁰ C, carbonylation can be carried out at room temperatures due to the weight of the precipitation of reducible 30. There are, however, advantageously nickel and cobalt compounds used without further ER- temperatures of 40 to 100 ⁰ C to attraksichtlich. The term "reducible vertical carbonylation rates to achieve binding" as used herein is intended to mean oxides, higher temperatures should be avoided at these moderate hydroxides, carbonates and their mixture pressures, since they are the extraction of the. Lower nickel and 35 nickel basic carbonates.

As already mentioned, cobalts can thereby be an advantageous embodiment of the present invention be formed that from the corresponding ammonia invention is the catalyzing of the nickel-carbonylic ammonium carbonate leaching solutions and the suppression of the cobalt-carbonyliemonia and carbon dioxide are distilled off. Such reaction reactions by using the reduced metal Basic carbonates can also be made 40 controlled amounts of sulfur in active form if one provides nickel and cobalt salt solutions with water, d. that is, the sulfur must be uniformly distributed throughout the soluble carbonate or bicarbonate, such as sodium-induced metal, carbonate or sodium bicarbonate. The sulfur or sulfur containing materials Hydroxides of nickel and cobalt can be used before or during the reduction and / or be formed by adding to acidic aqueous 45 during the carbonylation. When Solutions in which nickel and cobalt is dissolved, then bases, the sulfur is added before the reduction like sodium hydroxide, potassium hydroxide, ammonium it can be very beneficial to the aqueous sludge hydroxyd and other bases added. The oxides of the reducible nickel-cobalt compounds in Cobalt and nickel can be formed if a water-soluble or a gaseous form one the carbonates, basic carbonates, hydroxides 50 sulfide, z. B. as sodium or potassium sulfide or or the sulphides of nickel and cobalt are dried and / or hydrogen sulphide is added. He can also go before or calcined. or during the reduction in the form of sulfur

Another important feature of the present compounds, such as nickel sulfate, are added. Invention is the reduction of the reducible compound. The sulfur can also be used as a solid before the reduction bonds of nickel and cobalt to metals 55 sulfidic material, e.g. B. as pyrite, are added., at temperatures not higher than 375 ° C. The sulfur can also be in during the reduction If the reduction is carried out at temperatures above 400 ° C in the form of reducible gaseous sulfur, then less than 75% of the compounds, such as sulfur dioxide, will be added. the Nickel after the subsequent carbonylation al: Sulfur can also preferably be used after the reduction gaseous nickel carbonyl obtained. To technically 60 in the form of a reactive gaseous sulfide, such as To achieve acceptable reduction rates, hydrogen sulfide or carbon oxysulfide is added will generally be used in performing the. In all cases it is advantageous to ensure an equal-reduction temperature of at least 225 ° C with a deformed distribution of the sulfur, turns. In addition to the potassium allylic effect on the carbonylic atmosphere, which reduces nickel oxide, sulfur, if it is in the active form, can be used for this reduction, such as hydrogen and carbon monoxide, including the yield of nickel as nickel-sowic their mixtures that increase with inert gases or with carbonyl. Presumably cobalt forms as well oxidizing constituents can be diluted or optionally present iron with the nickel

7 8

during the reduction a solid solution containing the carbon monoxide left behind is collected gaseous nickel-nickel during the carbonylation less active carbonyl, which makes the above described, and the sulfur now reacts with the cobalt manner. Due to the continuous removal of iron and the effects of these metals removal of the nickel carbonyl from the carbonylie in the solid solution to a minimum. The material containing the carbonylation reaction is made more powerful in such amounts that the reaction is added in full so that the sulfur content of the reduced material runs off at a greater rate between 0.05 and 5%. The carbonylation residue, in which nickel can have sufficient catalytic effects of sulfur and cobalt ratios as low as 1: 3 or even lower with the possible formation of carbonylation, can be done in the conventional cobalt and / or iron sulphide-related manner Obtaining the cobalt in salable, the sulfur-containing "material is treated in such a form. So the residue can be added in amounts that 0.2 moles to 2 moles of sulfur, for example, are redissolved, and the cobalt per mole of cobalt and / or iron may be provided by liquid or solid ion exchange. In general, the higher the proportion of the shear process recovered. The cobalt and sulfur containing material within which the nickel can also be further separated by adding said range is, the higher the maximum selective precipitation after dissolution ale reduction temperature (up to 400 "C) that takes, e.g. B. by adding water-soluble sulfi, and the lower the earth or by reduction with hydrogen, necessary carbon monoxide pressure for the Carbonylie- 20 The invention is illustrated in the examples, and the lower the cobalt content of the ver. volatile nickel carbonyls. However, if excessive amounts of sulfur are added to Example 1, then a sample was obtained which decreased 41.2% nickel and the final nickel extraction because there was S% cobalt, ie a nickel-to-cobalt ratio of some nickel contained the sulfur with formation of Sul as 8.25: 1, by combining a nickel and cobalt halide, which is not readily reduced ammoniacal ammonium carbonate solution and carbonylated. This is particularly true when the heating is carried out, whereby ammonia and carbon dioxide are at the moderate pressures which are distilled off during carbonylation and the basic carbonates of nickel are used. The sulfur containing carbon and cobalt were precipitated. This batch should bonds therefore advantageously züge- 30 for 4 hours reduced at 300 ⁰ C in hydrogen, will provide that 0.75 to 1.5 moles of sulfur per mole of sulfur before reduction was to be provided in the form of cobalt enough. If copper is present in the reducible sodium sulfide (Na _x S) added to the nickel compound or in the reduced metal with a 3% sulfur content, then additional amounts should be added, ie a sulfur-to-cobalt molar ratio of sulfur within the above 35 0.54: 1 ratio. The reduced metal product ratios are provided. was cooled without reoxidation and then with

The nickel carbonyl is made from the carbonylation carbon monoxide at a partial pressure of 10 atmospheres

reaction collected by taking the spheres from the carbony and at a temperature of 6O ⁰ C for 17 hours

Lienmgsreaktor exiting gases compressed and / the long treated. Through the carbonylation treatment

or cools down. The compression and / or the ablation was 98% of the nickel in the reduced

Cooling of these gases provides a method of separating metal product extracted The carbonylation back-

The use of nickel carbonyl along with other stands contained 96% of the cobalt in the reduced

Metal carbonyl compounds of carbon monoxide metal product, so that less than 4% of the cobalt is in

The carbon monoxide can then reappear in the nickel carbonyl, i.e. H. the nickel-to-

Carbonylation reactor are recycled. The 4S cobalt ratio in Niekel-Carbony! was greater than

liquid carbonyl compounds can be fractionated 200: 1.

be distilled, with nickel-carbonyl, which was used for comparison purposes, a batch of the same

essentially of iron and, of course, of cobalt chen composition under the same conditions

is free, first distilled off By decomposition of the treated with inclusion of the addition of sulfur,

distilled nickel carbonyl can be used, however, with the exception that the carbonylation

common forms of essentially pure nickel only react under one atmosphere of pressure

getting produced. For example, the nickel-carbon monoxide was made. Under otherwise

Carbonyl thermally decomposed, whereby nickel-like conditions became even after 17 hours Pellets or nickel powder and carbon monoxide only 64% of the nickel is extracted,

stands the latter can in the carbonylation reaction 55 _a .. ". ,, -

to be led back. Example 2

The carbonylation reaction can be carried out in any device. This example demonstrates the fact that lower The process can be carried out in a batch-wise, technically acceptable manner, or on a continuous basis. So yield 60, fine series of three batches, For example, fluidized bed reactors, rotary kilns containing 41.2% nickel and 5.0% cobalt, i. H. a nickel or multiple furnaces can be used, provided that they contained a to cobalt ratio of 85.2: 1 and the Good gas sealing is achieved by heating a material containing nickel and cobalt

Advantageously, regardless of whether the ammoniacal ammonium carbonate solution is obtained

run continuously or intermittently 65 were carried out in hydrogen for 4 hours

carbon monoxide is heated with the required part - 300,400 and 500 ° C. Enough sulfur has been heated

pressure continuously added to the carbonylation reactor as NatS sludge before the reduction, that

joined and drained from it. The continuously from- the reduced metal with a sulfur-to-cobalt-

2490

Molar ratio of 0.29, or 0.38 and 0.27 was provided.

The reduced metal product was cooled without reoxidation and then treated with carbon monoxide at a partial pressure of 10 atmospheres and a temperature of 60 ° C. for 17 hours. The carbonylation treatment reduced 98.6, 66.4 and 41.2% of the nickel in the products at temperatures of 300 and 400 and 500 ^° C., respectively. As shown in Table I, the extent of volatilization depends on the Nickel significantly depends on the pre-reduction temperature. Reduction temperatures below 300 ° C. give similar extraction results, but the rate of reduction is drastically reduced.

Table I.

S: Approx Molar ratio

0.29 0.38 0.27

Carbonylation pressure

at CO

10 10 10

Reduction temperature

300 400 500

Nickel extraction

'/. 1 hour I 17 hours

39.5

34.9

7.2

Example 3

A series of six samples of basic carbonate containing 41.2% nickel and 5% cobalt (obtained from ammoniacal ammonium carbonate solution) were slurried with aqueous sodium sulfide solution to give sulfur to cobalt molar ratios ranging from 0.25 to 1.0 obtained (see Table II). The slurries were filtered off and the sulfiding carbonates were reduced for 4 hours at 300 ⁰ C with hydrogen. The reduced products were cooled without re-oxidation and hieraul treated with carbon monoxide for 17 hours at 60 ⁰ C. The six samples were treated in two series, namely three samples at 5 atmospheres of carbon monoxide and three samples at 10 atmospheres of carbon monoxide. The samples were selected to cover a wide range of sulfur-cobalt in both rows.

The addition of sulfur has three effects:

1. catalyzing the volatilization reaction of nickel,

2. Suppression of the formation of cobalt carbonyl,

3. Lowering the final nickel extraction for high sulfur-cobalt ratios.

In Table II is the catalytic effect for the Experiments with 5 atmospheres recognizable at the end *

ao, with sulfur-cobalt molar ratios of 0.25, 0.50 and 1.00 nicket volatilizations of 49.4, 69.1 and 94.0 respectively. The effect of suppressing cobalt is clearly shown in the same way: The nickel-cobalt ratios increase

as from 135 to 1900 and 26000 for sulfur-cobalt molar ratios of 0.25 and 0.50 and 1.0, respectively. In which higher pressure (10 atmospheres) the catalytic effect of high sulfur contents is not as significant. The cobalt suppression remains, however

another important factor: to the extent that the sulfur-cobalt molar ratio from 0.32 to 0.52 and 0.73 is increased, the nickel-cobalt extraction ratio increases from 131 to 226 and 995, while the final nickel extraction drops slightly, namely from 98.6 to 98.0 and 97.0.

Table II

S: Co Carbony Weight Ni Residue S. Ni extraction Ni / Co Mole lieningsdruck 57.3 V. 2.5 49.4 V. 135 ratio at CO ^ 26.9 46.1 Co 5.5 69.1 Co 1900 0.25 5 24.0 12.1 13.8 19.0. 94.0 3.0 26000 0.50 5 13.6 7.6 18.8 11.6 98.6 0.3 131 1.00 5 7.6 9.8 35.2 14.6 98.0 0.03 226 0.32 10 9.9 11.5 39 _S 5 19.1 97.0 6.2 995 0.52 10 11.5 39.6 3.6 0.73 10 40.1 0.8

• Sample = 41.2 "/. Ni, 5.0% Co, 8.25 · /. Ni / Co. Reduction 4 hours at 300 ^° C. in H _1. Evaporation 17 hours.

Example 4

A sample of lateritic ore containing 1.18% Ni, 0.15 % Co, and 45.1 % Fe , to which V ₁ % by weight of pyrite had been added, was treated for 4 hours at 600 "C with a gas that was 40 % carbon monoxide and 60% carbon dioxide contained, selectively reduced. the reduced material was cooled without reoxidation at 60 ^D C, and then treated with carbon monoxide at a partial pressure of 5 atmospheres for 17 hours, the carbonyl-extracted residue was placed in a animoniakalische ammonium carbonate solution containing 6 The residue was leached with this solution at 65 ° C. with aeration.

By the carbonylation treatment, 91.5% of the nickel was extracted to give a carbonyl

product was obtained that is based on 1 part of nickel O, 73 parts < Iron and less than 0.0001 part cobalt contained by treatment with ammoniacal Am monium carbonate were another 3.5% of the nickel; along with 81.5% of the cobalt leached Dk

Distillation of this leach solution gave a basic: Carbonate, which nickel, cobalt and etsen in the rage Ferries ratio 1: 3: 0.01 contained The carbonai can be according to the conventional treatment menu be subjected to extract the cobalt

A similar sample of a lateritic ore men together with Vi weight percent pyrite was added 4 deferment at 600 ⁰ C with a gas containing 40% and 60% Kohlenmonoxyc .Kohlendioxyd selectively reduced

The reduced material was cooled without re-oxidation on 6S ⁰ C and placed in an ammoniacal ammonium carbonate solution containing 6 weight percent ammonia and 4 weight percent of carbon dioxide. The residue was leached with this solution at 65 ° C. with aeration: This leaching extracted 93.5% of the nickel together with 80 to 82% of the cobalt. Distillation of this leach solution gave a basic carbonate containing nickel, cobalt, iron in an approximate ratio of 1: 0.11: 0.01. The basic carbonate was slurried with an aqueous sodium sulfide solution to give a sulfur to cobalt molar ratio of 0.82: 1 in the solids. The slurry was filtered off and the basic carbonate was ^{reduced under hydrogen at 30O 0} C for 4 hours. The reduced material was cooled to 60 ° C. without reoxidation and then treated with carbon monoxide at a partial pressure of 6 atmospheres for 17 hours. The carbonylation treatment extracted 97% of the nickel originally present in the carbonate, whereby a carbonyl product was obtained which contained 0.002 part cobalt and 0.002 part iron per 1 part nickel. The residue from the carbonylation contained nickel, cobalt and iron in an approximate ratio of 1: 3: 0.2. This residue can be subjected to the usual treatment methods for the recovery of cobalt.

On the basis of these two modes of operation it can be seen that the selective reduction, which is directly involved Leaching with ammonia follows, inasmuch as the weight of the in the pressure reactor increases processed material is less than 2% of the weight of the ore charge which is followed by the carbonylation is also advantageous in that the carbonyl product is one has much lower iron content than that obtained by direct volatilization.

40

Example p

This example demonstrates the fact that the effect of the reduction temperature is not as dramatic when sulfur levels are used within the preferred sulfur to cobalt ratios. Contained four samples of a basic Carbonatniederschlags, the 44.8 * / · nickel, 4.75% cobalt and 1.88% sulfur, 4 hours at 300 "C, 325 ⁰ C 350 ⁰ C and 375 ° C were reduced in Wassesrtoff Sufficient sulfur was added to each sample prior to reduction to provide sulfur to cobalt molar ratios of 0.99, 0.88, 0.93, and 0.85 in the reduced metal samples, and the reduced metal samples were under 10 atmospheres carbon monoxide for 20 hours carbonylated at 6O ⁰ C. the results obtained are shown in Table III together It is apparent that if the advantageous sulfur-to-cobalt mole ratios are used, the WIR effect of the reduction temperature on the nickel extraction itself up to 375 ° C is not recognizable. The effect of the 'reduction temperature becomes more apparent when approaching 400 ° C. The results in the tables also show that higher reduction temperatures, while they lower the nickel extractions, the ratio of the e Increase extracted nickel to cobalt.

Table III

Reduction temperature ^{0 C}

S: Co Molar ratio

0.99 0.88 0.93 0.85

98.8 96.5 96.8 91.3

6.7 5.8 5.3 3.5

Ratio of

extracted

Ni: Co

139: 1 158: 1 172: 1 246: 1

Claims (13)

Patent claims: 1. Process for the separation of nickel, of cobalt and, if present, of iron, in which reducible nickel and cobalt compounds are reduced ^{to metal by heating in a reducing atmosphere to a temperature of less than 400 0} C and the metal product obtained at a Carbonylated at a temperature of less than 100 ^° C. and the nickel carbonyl is separated from the cobalt, characterized in that the reducible metal compounds are precipitated from an aqueous solution and separated and carbonylated at superatmospheric pressure of less than 15 atmospheres. 2. The method according to claim 1, characterized in that the aqueous solution is a leaching solution which is used in the leaching of cobalt-containing and nickel-containing oxide ores. 3. The method according to claim 2, characterized in that the leaching solution is the product of the Leaching of a selectively reduced lateritic ore with an ammoniacal ammonium carbonate solution with aeration and that the Precipitation caused by distilling off ammonia and carbon dioxide from the Auslang solution which causes basic carbonates to precipitate, which are reduced at less than 375 ° C, and the nickel carbonyls together be separated with the iron carbonyls. 4. The method according to claim 2, characterized in that the leaching solution from the leaching of a lateritic ore which is more than 40% Contains iron, originating with sulfuric acid at 230 to 260 ° C in an autoclave, which causes precipitation Addition of a water-soluble base or a water-soluble carbonate to the leach solution occurs and that the reduction is less than 375 ° C is made and the nickel carbonyls together with the Eiseo carbonyls be separated. 5. The method according to claim 3 or 4, characterized in that the nickel and iron car bonyle are cooled to form a liquid and that the nickel carbonyl is separated by fractional destination. 6. The method according to any one of the preceding talks, characterized in that at least! some of the carbon monoxide from decomposition reaction of the carbonyls is returned. 7. The method according to any one of the preceding claims, characterized in that the reductive tion at temperatures of 225-340 ⁰ C is easily taken. 8. Method according to one of the introductory An 2490 13 14 Proverbs, characterized in that the catalyst 10. The method according to one of the preceding ization of the carbonylation 0.2 mol to. 2 Mol Proverbs, characterized in that the column Sulfur per mole of cobalt in the reduced metal monoxide partial pressure is 6 to 12 atmospheres be provided for the product. wearing. 9. The method according to claim 8, characterized in 5 11. The method according to any one of claims 1 to 10, characterized that the proportion of sulfur is 0.75 to characterized in that the carbonylation 1.5 moles. above 40 ⁰ C is made. 249a-