DE2240770B2 - METHOD FOR REFINING NICKELSTONE - Google Patents

Description

The invention relates to a method for refining nickel stone.

The extraction of nickel from sulfidic ores, which contain both nickel and copper, is often carried out by the Presence of copper difficult. Such ores are often processed pyrometallurgically Nickel and copper sulphides melted. In the case of a nickel ore, e.g. B. with a ratio of nickel to Copper greater than 5: 1, the molten nickel sulfide must be refined. Until recently there was no such refining process is known. With the exception of two methods described below The treatment of nickel sulfide-rich melts unchanged a solidification mute before the copper is removed will. For example, molten nickel sulfide is poured into anodes and the nickel suffid anodes are made Electrolyzed or molten nickel sulfide is used to obtain nickel and elemental sulfur solidified, pulverized and then refined. Most commonly, solidified nucleus sulfide is used to produce Roasted nickel oxide and the nickel oxide for further purification either by electrorefining or reduced by carbonylation Recently it was proposed that solid nickel sulfide for the chlorination of impurities such as copper, selectively chlorinate, and leach the selectively chlorinated impurities from the solid nickel sulfide remove. All of these methods have the disadvantage that they require an intermediate solidification step and are relatively slow compared to that in the The kinetics obtained from treating molten nickel sulfide proceed.

Recently, two methods of removing copper sulfide from molten nickel sulfide have emerged been hit. In US-PS 30 69 254 a variation of the well-known so-called "ground copper" - Procedure described. According to US-PS 30 69 254, the molten solution of nickel and Copper sulfide with a molten solution of sodium sulfide and sodium chloride or other alkali or alkaline earth chlorides treated to the copper sulfide selectively dissolve and produce purified nickel sulfide. After this decay one can only Separate copper sulphide from nickel sulphide while other sulphides are not affected by the treatment * will. It has also been suggested to use impure nickel sulfide with a nickel chloride and alkali or To treat slag containing alkaline earth chlorides for cleaning the nickel sulfide. Slag, the Umset products between bases and silicon dioxide are have relatively high melting temperatures. In extractive nickel metallurgy, temperatures applied above 1200 ° C to ensure that the slags used remain in the liquid state. Any process that requires the incorporation of nickel chloride into a slag will be quite ineffective, as nickel chloride at temperatures that are slightly above 1000 "C, sublimed, which is well below the temperatures required for slag. In any case, most of them can Slag only small amounts of nickel chloride even in the presence of alkali and / or alkaline earth chlorides dissolve and hold back so that excess nickel chloride is evaporated from it. the end Nickel chloride evaporated from such slags is oxidized, making the process even more ineffective will. Another disadvantage of using slags as a carrier for nickel chloride is that that the recovery of nickel and the impurities trapped in the slag are difficult is. The presence of silicon dioxide and bases in the slag causes that nickel chloride and chlorides, the present as impurities cannot be electrodeposited. The one in education cause the high temperatures applied to the slag and the amorphous nature of the solidified slag, that the slag for other recovery processes, e.g. B. hydrometallurgical processes, chemically inactive will.

In the German Offenlegungsschrift 20 56 001 is a Process for cleaning iron- and cobalt-containing nickel stone described, in which the to be cleaned, with an alkali metal chloride or an alkali metal

Allcöloridmisdiung-covered stone melts, to convert the iron and cobalt impurities contained in the stone into the chlorides FeQ ₂ and CoCi _2, blows gaseous chlorine, the bath then stirs, the stone cleaned in this way and one made of nickel, cobalt and iron chlorides such as separates slag consisting of the alkali metal chloride used by decanting during cooking and treating the chlorides to their value increasing in order to separate the nickel from the cobalt.

In this known method, a maximum of 40 wt .-% chloride extractant, based on the molten nickel sulfide, used. The consumed extractant is used to recover the metal values treated from it in solid form -

The present invention has for its object to provide a method according to which Nickel stone can be refined with a chloride extractant without applying excessively high temperatures k * nn and where the molten extraction medium can be regenerated directly for reuse.

The invention relates to a process for refining nickel stone which contains at least 60% nickel and not more than 26% sulfur, a protruding, liquid extraction layer of at least one alkali or alkaline earth chloride (including magnesium chloride) being added to a molten bath of nickel stone The mixture is brought into contact with chlorine and / or nickel chloride, the chlorinated impurities are extracted into the extractant layer and the molten extractant layer is separated, which is characterized in that a weight ratio of nickel stone to chloride extractant of 2: 1 to 1: 3 and the refining between 750 and 900 ⁰ C is carried out, and that the extraction medium is regenerated in the molten state and the regenerated melt is returned to the process.

The method according to the invention differs from that from the German Offenlegungsschrift 20 56 001 known method:

(a) in the ratio of nickel stone to extractant, with the tendency that the amount of the latter is chosen to be relatively large, d. H. 2: 1 to 1: 3, while this ratio in the known one Method 4: 1 to 2.5: 1. preferably 3.3: 1, amounts to;

(b) in the preferred temperature range 750-900 ⁰ C, while according to the German Offenlegungsschrift 20 56 001 temperature range at 750 to 1000 ° C, preferably at 900 to 950 ° C, is located, and

(c) in the regeneration of the extractant in the molten state and in the recycle the regenerated melt in the process, while according to the known method the comparable chloride slag is withdrawn and then dissolved and in the solid, crushed state is further processed.

According to the method according to the invention, it is possible to use pure nickel sulfide in an economical and easy way to manufacture.

Many nickel sulfide containing materials, regardless of the manner in which they are made, can be treated in accordance with the invention. For reasons of economy and overall operation, however, it is advantageous to use a nickel sulfide material or nickel stone that contains at least about 60% nickel, for example about 70% or more nickel and no more than about 26% sulfur, for example 18 to 24% sulfur, and a has a chlorineable total impurity content of not more than 15%. The chlorinated contaminant content should preferably not exceed 12%. As will be shown below, greater amounts of contaminants are removed when the stone contains an excess of sulfur, that is, when the stone contains less than about 21% sulfur or less sulfur than is necessary to meet the stoichiometry of Ni ₃ S ₃ . However, the sulfur deficiency should not be so great that the melting point of the block is above 900 ⁰ C, i.e., the sulfur content should not be less than 18%, · <λ that the liquid-liquid extraction at a temperature of 750 to 900 ⁰ C can be carried out. Chlorinatable impurities that can be removed from the nickel stone according to the invention are, for. B. cadmium, cobalt, copper, iron, lead, manganese, tin and zinc. These impurities are preferably not present individually or together in amounts above 12%, since otherwise larger and more uneconomical amounts of the chloride extraction agent have to be used. The level of> certain impurities can be reduced to less than 1% by pretreatment, e.g. B. Iron can be removed by blowing and slagging. When the chlorinatable impurities are present in the amounts listed above, they can in most cases be reduced in one or more stages to an amount of less than 0.05%, e.g. B. the lisen content from originally 1% to less than 0.02%, the cobalt content from originally 5% to less than 0.02%, the copper content from originally 10% to less than 0.02%, the lead content from originally 0 , 25% to less than 0.002%, the cadmium content from the original 0.2% to less than 0.005%, the zinc content from the original 2.0% to less than 0.5% and the tin content from the original 0.2% to 001% . The compositions are on a weight basis unless otherwise specified.

As stated above, the nickel stone is refined according to the invention at a temperature of 750 to 900.degree. Temperatures above 900 ^° C. can be used, but higher nickel losses occur as a result of the increase in the partial pressure of nickel chloride and pressure or closed vessels must be used in order to minimize losses associated with these high partial pressures of the nickel chloride. Higher temperatures also favor heat losses. Accordingly, in terms of reaction rates, chloride loss and heat considerations, it is advantageous to carry out the chlorination treatment at a temperature of 750 to 900 ° C.

An important feature of the present invention is the use of a supernatant molten chloride extractant to collect the chlorinated impurities. The use of such an extractant gives particularly good results, especially when gaseous chlorine is used as the chlorination reagent. The extractant is at least one chloride of a metal from group IA or HA of the periodic table, ie chlorides of the alkali and alkaline earth metals. The extractant should have a melting point below 800 ⁰ C and a vapor pressure which is not more than 0.25

Atmospheres at 800 ⁰ C, have. Of course, a mixture of chlorides can be used as extractants. This has a lower melting point, the term "Erdakalimetall" includes magnesium, which is a chloride with a melting point of 708 ⁰ C and a boiling point of 1,412 ° C forms from physikalsichen standpoint Can chlorides of sodium, potassium, rubidium, magnesium and calcium individually applied while strontium and barium chlorides can only be used in combination with at least one of the chlorides listed above.

The chloride extractant must be able to dissolve nickel chloride and chlorinated impurities. The chloride extractant should dissolve up to 1% nickel chloride and preferably even up to 20% nickel chloride. For overall effectiveness in minimizing nickel losses due to evaporation of nickel chloride , the chloride extractant contains from 15 to 5% nickel chloride. If the chloride extraction agent does not dissolve nickel chloride, nickel chloride, which has a considerable vapor pressure even at temperatures as low as 850 ^° C., is lost to the ambient atmosphere through evaporation from the system. The absence of nickel chloride in the extractant system, the process can not be performed because no nickel chloride to react with the contained in the Sulfidbad impurities is available for the overall effectiveness of the removal of a predominant portion of the impurities, which occur most commonly nickel sulfide, it is advantageous use a molten chloride extractant which contains equal amounts of sodium and potassium chlorine

The chlorination of the impurities can be carried out in such a way that good liquid-liquid or gas-liquid contact is ensured. which depends on the state of the chlorinating agent. If gaseous chlorine is used as the chlorination reagent, this is advantageously carried out through the nickel stone in the form of small, well-dispersed bubbles. For example, a suitable vessel can be equipped with one or more porous plugs through which the chlorine is passed, whereby the chlorine is introduced into the nickel stone in the form of small, well-distributed bubbles. However, if nickel chloride is used as the chlorination reagent, it is advantageously dissolved in the molten extractant and good liquid-liquid contact between the lower stone layer and the supernatant chloride extractant is ensured by mixing either by mechanical, electromechanical or pneumatic stirring

When impurities in nickel stone are chlorinated by using nickel chloride dissolved in the chloride extractant, the process can be carried out either batchwise or continuously. When carried out batchwise, one or more treatment steps can be carried out. If the method is carried out on a continuous basis, the principles of countercurrent can advantageously be applied. An equilibrium between the molten extractant and the molten nickel stone is quickly reached. This rapid Reaktionsgeschwindig- fts ness is an important feature of the process since it allows the use of a number of steps, without much additional heat input at each stage of the process is preferably in the countercurrent in a tower assembly carried out For example, molten impure nickel matte at the upper end of a tower provided with baffle, while molten chloride extractant is introduced at the lower end of the tower * in such a way that the soot of the nickel stone in the downward direction and the flow of the molten extractant in the upward direction produce the desired countercurrent liquid-liquid contact In order to ensure that the molten nickel sulfide is treated batchwise and continuously, ratios of stone to extractant between about 2: 1 to 1: 3 are used to ensure that the nickel stone is refined to the desired extent d. Lower stone to extractant ratios can either be used, but such lower ratios present material handling problems. Higher stone to extractant ratios can be used, but the stone is not sufficiently refined. The purified nickel sulfide can be treated by conventional methods to produce nickel or nickel oxide. After molten nickel matte is highly purified by employing the present invention, it is very advantageous to blow the surface of the turbulent molten matte directly into nickel metal in a gas containing free oxygen. After vacuum desulfurization, deoxidation and degassing of the nickel bath, the nickel can even be cast on a continuous basis to produce a nickel metal product. which is suitable for most applications

The loaded chloride extractant, the essential Amounts of nickel chloride and chlorides of impurities contains, is used in the molten state for the regeneration of the chloride extractant and for Treated recovery of nickel and valuable impurities. For example, is the mother chloride extractant into an electrolysis / rush, which leads to a graphite container that acts as a cathode acts, and contains a graphite anode. The nickel and the impurities are called metal alloy powder ver by electrolysis of the molten Chloridex traction agent at a temperature of 700 to 900 C. recovered at an electrical potential of about 1.5 to 10 volts.

Current densities of 1000 A / 0.09 m ² and even more can be used. As the amount of metal powders generated increases, there is a remarkable decrease in electricity efficiency. Chlorine gas is generated at the anode and returned directly to the chlorination plant or used to generate nickel chloride which is dissolved in the extractant. After the electrolysis reaction is complete, the regenerated extractant can be returned directly for further use or treated for the addition of nickel chloride to it before reuse as an extractant.

Preferably the loaded molten extractant is made up of magnesium or a magnesium alloy to separate the nickel and the chlorinated impurities as a molten magnesium alloy treated by exchange reaction. Magnesium or its alloys are added to the loaded extractant in amounts that between about 1 and 2 mole equivalents of magnesium

for every mole equivalent of base metals in the loaded extractant. Since magnesium is a has a lower density than chloride extractant, it is very advantageous to use a magnesium alloy, which contains at least 6% nickel or copper. The best results are achieved by adding a magnesium alloy obtained containing 5 to 30%, e.g. 6 to 15% nickel or copper. The magnesium alloy is supplied to the loaded extractant in particulate form, while the extractant on a Temperature of 750 to 900 ° C is maintained. It is advantageous to have the loaded chloride extractant in to maintain a turbulent state by mechanical, electromechanical or pneumatic means in order to avoid the To facilitate reaction between the magnesium and the chloride extractant. The purified extractant can be returned to the chlorination treatment, while the alloy containing nickel, Contains cobalt, copper, iron and other impurities, treated to recover these elements will Da the magnesium content of the chloride extractant grows continuously, it is advantageous to use the extractant loaded with magnesium Electrolytic treatment to recover the magnesium for further use. That Magnesium can be recovered from the extractant in electrolytic cells, which in conventional Way to be used for the extraction of magnesium from magnesium chloride. In the electrolysis treatment Magnesium is produced for cleaning the loaded extractant, a low magnesium salt and chlorine, which goes back to the chlorination refining can be traced back from Nickelstein.

The extractant containing magnesium chloride can be obtained either by passing through chlorine, which as js By-product of electrolysis is obtained by a portion of the purified stone that is obtained from the supernatant molten chloride extractant layer, or by the extraction process be regenerated. Uni quick and effective regeneration of the molten nickel chloride containing it Extractive agent to ensure regeneration is carried out at a temperature of 750 to 800 ° C carried out with the chlorine in small bubbles through at least 10 inches of the molten nickel sulfide boils through

The following examples illustrate the invention.

example 1

Impure nickel stone, which contained 26.4% sulfur, 0.65% copper, 0.78% cobalt and the remainder essentially nickel, was ^{heated to a temperature of 780 °} C. and treated with molten sodium chloride containing 10% nickel chloride. The reaction between the molten chloride extraction and the nickel star was discontinuous and the ratio of nickel stone to chlorine extractant was about 1: 1. fo

The so refined nickel stone contained £ 0% copper. 0.1% cobalt and 72.6% nickel. The liquid chloride extractant had a final analysis of 0.4% copper. 0.46% cobalt and 150% nickel. The nickel contained in the loaded extractant. Cobalt and copper was made from the extractant as alloy powder by electrolysis in a similar manner, as described in Example 8. regained.

' 8th
Example 2

This example confirms that stones that are lower in sulfur are cleaned to a greater extent than stones that contain greater amounts of sulfur. The analyzes of the nickel stones are given in Table I. Molten nickel stone was treated discontinuously ^{at 780 °} C. with liquid sodium chloride containing 10% nickel chloride.

Nickel stone to chloride extractant ratios of 2: 1 were used. The final analysis values of the nickel stones and the chloride extractants are also given in Table 1. From Table I it can be seen that the final copper and cobalt analysis values were lower in Stone B, the lower-sulfur stone. The loaded extractants were treated in a manner shown in Example 8 to electrodeposit an alloy powder containing nickel, cobalt and copper.

Table 1

Analyzes
Cu Co
%% 0.68
0.16
0.90 S.
0/0 Ni
% Experiment A:
Untreated stone
Refined stone
Loaded extractant 0.74
0.28
0.71 0.58
0.10
0.77 23.2 2.3 Experiment B:
Untreated stone
Refined stone
Loaded extractant 0.64
0.22
0.64 19.6 2.76 Example 3

This example confirms the effectiveness of countercurrent extraction. A nickel stone containing 26.6% sulfur, 0.87% copper, 1.01% cobalt and 0.22% iron and the remainder essentially nickel was added with a chloride extractant consisting of sodium chloride with 10% nickel chloride 780 ° C at a stone to chloride extractant ratio of 2: 1. After the first stage of extraction the stone contained 0.5% copper, 0.3% cobalt, 0.026% iron and 72.1% nickel and after the second stage extraction the stone analysis values were 025% copper, 03H cobalt. 0.01% iron and 723% nickel. The first stage chloride extractant contained 033% copper. 0.01% cobalt, 0.22% iron and 2.7% nickel, while the extractant of the second stage contained 0.48% copper, 037% cobalt 0.045% iron and 3.19% nickel.Thus, that increased between the first stage and the second stage of the extractions Nickel-to-copper ratio in the stone from about 144: 1 up to about 290: 1. The nickel-to-cobalt ratio in the stone was increased from about 180: 1 to about 900: 1 and the nickel-to-iron ratio in the stone from about 2800: 1 to about 7300: 1. A nickel-copper-cobalt-iron alloy powder was separated from the loaded extract clay in a manner similar to Example 8, and the extractant regenerated for subsequent reuse

Example 4

This example confirms the improved results obtained using low sulfur nickel stones, the countercurrent flow principles, and lower nickel stone to extraction media ratio. Nickel stone, which contained 20% sulfur, 0.8% copper, 0.78% cobalt and 0.38% iron and the remainder essentially nickel, was added in three countercurrent stages with a chloride extractor consisting of sodium chloride and 10% nickel chloride 780 ⁰ C contacted. The total amount of chloride extractant used was such that a total stone-to-chloride extract

Table Il

agent ratio of 1: 1 was used. the Final analyzes of the stone and the chloride extractant are given in Table II. From this Results show that between the untreated stone and the refined stone, the nickel-zü Copper ratio of 100: 1 down to about 5000: 1, that Nickel-to-cobalt ratio from about 100: 1 to about 20,000: 1 and the nickel-to-iron ratio of about 50: 1 to about 9000: 1. The loaded extractant was as described in Example 8 is electrolyzed to deposit an alloy powder and to regenerate the extractant

Nickel stone Cu

Extraction center

Co

Fe% Cu

Co

Fe

Ni%

Untreated stone I. stage

2nd stage

3rd stage

0.8 0.24 0.087 0.016

0.78 0.067 0.008 0.009

0.38 0.016 0.028 0.009 0.75 0.19 0.047

0.57

0.068

0.013

0.13 0.04 0.032

3.58 2.0

4.4

Example 5 Table III

This example confirms the importance of maintaining a supernatant chloride extractant on the surface of the molten stone during the chlorination treatment. A nickel stone sample having the composition shown in Table III was provided with a supernatant layer of a chloride extractant containing equal amounts of sodium chloride and potassium chloride. The stone to extractant ratio was 5: 4. The stone and the sample were kept at a temperature of 800 ° C. and gaseous chlorine was passed through the nickel stone at a rate of 0.4 l / min per kg stone for 2 hours. The refined stone and loaded extractant have the compositions shown in Table III. Another nickel matte, the demonstration given in Table IV composition was maintained at 930 ⁰ C, was bubbled chlorine gas while therethrough at a rate of 0.4 I / min per kg stone for 2 h. The refined stone had the composition given in Table IV. When comparing the refined stone compositions given in Tables Ii and IV, it becomes apparent that nickel stone is more thoroughly refined by the application of a supernatant layer of a chlorine extractant. Thus, in order to take full advantage of the chlorination treatment, it is essential to have an effective molten chlorine extractant and facilities for the economical regeneration of such extractants. The loaded chloride extractant was treated in a manner similar to that described in Example 8 to deposit a nickel-copper-cobalt-iron alloy silver to regenerate the chloride extractant analysis Cu Ni

Co Fe

Untreated stone Refined stone Final salt

Table IV

0; 86 76 0.59 0.14 21.1 0.16 - 0.03 0.04 233 0.72 10.8 0.55 0.15 -

analysis Cu Ni

Co Fe

Untreated stone 0.58 75.8 0.30 0.22 18.4 ^{Final salt} 0.31 74.3 0.20 0.13 203

Example 6

This example shows a 2-step stone raffma. tion method reproduceda A nickel stone, which had the composition shown in table V, ¹ was provided with a protruding layer of a Uiton extractant which contained equal amounts of sodium chloride and potassium chloride. The ratio stone to extractant was 3: 5.

u iT ^{tem and} * ^ε protruding extractant layer were kept at a temperature of 815 "C and gaseous chlorine at a rate of 0.4 l / min per kg stone through the nickel stone kjrü ^{2 h} SeMin. The refined stone and the oiled extractant of these first The refining stage had the analytical values given in Table V. After the loaded extractant from the first refining stage had been separated from the nickel brick, the nickel brick was included

provided an equal amount of a supernatant layer of chloride extractant containing equal amounts of sodium chloride and potassium chloride. While the stone and the extractant were kept at a temperature of 815 ° C, gaseous chlorine was again passed through the nickel stone at a rate of 0.4 l / min per kg stone for 2 hours reproduced in Table VI. From Table VI it can be seen that multi-step treatments are quite effective in producing highly refined nickel stones. The loaded chloride extractant for each refining stage was regenerated in a manner similar to that described in Example 8, and a nickel-copper-cobalt-iron alloy powder was recovered from the electrolytic treatment.

Table V

analysis
Cu Ni

Co

Vo

Fe

Untreated stone
Refined stone
Final salt

Table Vl

0.47 75.5 5.0 0.17 20.7
0.10 75.5 0.26 0.03 22.0
0.41 5.50 4.60 0.18 -

analysis
Cu Ni

Co

Fe

Refined stone
Final salt

0.02 74.0 0.017
0.10 11.9 0.035

Example 7

0.025 24.7 0.075 -

This example confirms the effectiveness of a chlorination treatment in removing impurities other than cobalt, copper, and iron. Nickel stone, which contained cadmium, lead, tin and zinc in the amounts shown in Table VII, was at 810 ^° C. with a chloride extractant containing the same amount of sodium chloride and potassium chloride and 12% nickel chloride, with a stone-to-extractant ratio of Treated 1: 1.5 The compositions of the refined stone and loaded extractant are shown in Table VIl. The loaded extractant, after separation from the refined stone, was electrolyzed in a manner similar to that described in Example 8 to produce an alloy powder containing nickel, lead, tin, cadmium and zinc

Table VII

analysis

Pb Sn
%%

CD

Zn

Example 8

This example confirms that loaded chloride extractant can be electrolyzed to produce alloy powders and regenerate the chloride extractant for reuse. An electrolytic bath containing 40 g sodium chloride, 40 g of potassium chloride and copper, nickel, cobalt and iron contained in the reproduced in Table VUI quantities, was prepared and maintained at a temperature of 800 ⁰ C. A potential difference of 2 V was applied to the graphite electrodes immersed in the loaded extractant and an anode current density of 83 A per dm2 was maintained. After 32 minutes, at least about 95% of the copper, nickel, cobalt and iron from the loaded extractant had deposited on the cathode while chlorine was evolved on the anode. The regenerated extractant, the analysis of which is given in Table VIII , was suitable for reuse for the chlorination treatment. Under these conditions, a current efficiency of 51% was achieved

Table VIII

analysis
Cu
% Ni
% Co
% Fe
% 0.58
0.002 £ 2
0.066 0.64
0.002 0.18
0.002 Original
Salt (80 g)
Final salt

Example 9

This example shows the electrolysis of a loaded extractant on a larger scale; an electrolytic bath containing 5000 g sodium chloride, 5000 g potassium chloride and copper, nickel, cobalt and iron in the amounts shown in Table IX was formed and maintained at a temperature of 780 ^° C. A stainless steel cathode and a graphite anode were immersed in the electrolysis bath and a potential difference of 2 V was applied to the electrodes. The anode current density was 60 A / dm ² , while the cathode ^{current density was 93 A / dm 2} . After a period of time prior to 6 hours, at least about 95% of the copper, nickel and cobalt had separated from the loaded extractant with a current efficiency of 53%. There; regenerated extractant, the composition of which is given in Table IX, was suitable for reintroduction into the chlorination treatment and the chlorine generated at the anode was returned to the chlorination treatment to chlorinate further impurities in the nickel stone

Table IX

analysis

Cu Ni% «te

Co

Fe%

Untreated stone 0.23 0.2 0.2 0.15 Original sentence 235 1.45 0.14 0.40 Refined stone 0.002 0.01 0.005 0.001 (10000 g) at 0.15 0.15 0.10 Final salt 0.02 0.01 0.013 0.05

Example 10

This example demonstrates that a loaded chloride extractant can be obtained by the addition of a magnesium alloy can be regenerated. A particulate magnesium alloy which has the characteristics set out in Table X indicated composition was in an amount of 1 mole equivalent of magnesium for each mole Equivalent of base metal introduced into the loaded extractant, which has equal parts of sodium and

Table X

Potassium chlorides and chlorinated metals in the in Table X contained amounts shown. The loaded extractant had a temperature of 750 ° C, as the magnesium alloy was added thereto, and

s was in a stirred state to produce a good liquid-liquid contact between the liquid magnesium alloy and the excess loaded Extractant held. The regenerated extractant was as shown in Table X.

ίο composition.

analysis

Cu

Ni

Co

Fe

Mg

Loaded extractant
Magnesium alloy
Regenerated extractant

2.73
2.70
0.007

10.9
8.35
0.015

4.40
2.85
0.007

2.65

0.095

0.045

0.88

Rest*)

9.28

*) The rest of the magnesium plus limited amounts of the oxygen associated with the magnesium.

Example Π

This example illustrates the cycle of the process according to the invention. A loaded extractant of the composition shown in Table XI and a temperature of 750 ° C was mixed with a magnesium alloy having the composition shown in Table XI in an amount of about one part of magnesium alloy for every 17 parts of loaded extractant in a manner similar to it is described in Example 10 , implemented. The regenerated extractant was obtained by the analyst shown in Table XI.

Molten nickel matte, the demonstration given in Table Xil composition and a temperature of 750 ⁰ C, was treated with gaseous chlorine in the manner described in Example 2 to produce a lot of stone, which was given in Table Xil analysis. During the chlorination treatment, the nickel stone was provided with a protruding layer of the regenerated extractant in an amount corresponding to about 3 parts of extractant for every 5 parts of stone, in order to collect the chlorinated impurities. The analyzes of the regenerated and loaded extractant are also shown in Table XII. This example confirms that the process can be cycled, thereby minimizing the cost of reagents and fuel.

Table Xl

analysis
Cu
% Ni
% Co
% Fe
% Mg
% Loaded extractant
Magnesium alloy
Regenerated extractant
Table XII
Stone chlorination with purified salt 3.05
2.7
0.003 7.75
8.35
0.005 0.65
2.85
0.005 0.56
0.09
0.032 74.8
4.2 analysis
Cu
% Ni
% Co
% Fe
% ü · Untied stone
Regenerated extractant
Refined stone
Loaded extractant 3.88
0.003
036
4.05 723
0.005
76.0
6.0 0.72
0.005
0.12
13th 0.22
0.032
0.085
1.65 4.2
5.0

Claims (8)

Patent claims: 1. Process for the refining of nickel stone, which contains at least 60% nickel and not more than 26% sulfur, wherein a protruding, liquid extraction layer of at least one alkali or Erdaikaüchlorid (including magnesium chloride) is added to a molten bath of nickel star, this molten mixture with chlorine and / oaer _{! O} brought into contact with nickel chloride, the chlorinated impurities extracted into the extractant layer and the molten extractant layer separated, characterized in that a weight ratio of nickel stone to chloride extractant of 2: 1 to t: 3 and the refining between 750 and 900 ° C are maintained is carried out, and that the extractant is regenerated in the molten state and the regenerated melt is returned to the process. 2. The method according to claim 1, characterized in that a chloride extractant is used containing 0.1 to 20 wt .-% nickel chloride. 3. The method according to claim 1, characterized in that chlorine in the molten nickel stone is blown in. 4. The method according to any one of claims 1 to 3, characterized in that the regeneration for Deposition of the nickel alloy and the generation of gaseous chlorine by fused-salt electrolysis is made. 5. The method according to any one of claims 1 to 3, characterized in that the loaded extractant is regenerated by adding magnesium or a magnesium alloy. 6. The method according to claim 5, characterized in that a magnesium alloy is used that contains at least 6% nickel or copper. 7. The method according to any one of claims 5 or 6, characterized in that part of the with Magnesium loaded extractant for the electrolytic recovery of magnesium is treated. 8. The method according to any one of the preceding claims, characterized in that the purified chloride extractant nickel chloride is added to the bath before addition / u 50