CS201026B2 - Method for the isolation of copper from metallic materials - Google Patents

Abstract

1399281 Extraction of copper ISC SMELTING Ltd 6 Feb 1973 [21 Feb 1972] 7945/72 Heading C1A [Also in Division C7] Copper values are leached from copper dross separated from lead bullion produced in the blast furnace smelting of lead or zinc lead by contacting particles of the dross in the form of a metallic lead matrix containing copper and copper compound inclusions with an aqueous solution of ammonium carbonate and ammonium hydroxide to dissolve copper from the dross. The leaching may be effected in the presence of the oxidizing gas or the leachate may be subsequently treated with an oxidizing gas. The ammoniacal solution is preferably a solution of (NH 4 ) 2 CO 3 and NH 4 OA and may contain SO 4 - preferably with a mole ratio CO 3 : SO 4 of 1 : 3. The leaching may be carried out in any conventional manner. The copper may be recovered from the leachate by contact with a copper-selective organic phase, e.g. one containing a hydroxy oxime, from which it may be extracted with an aqueous mineral acid (preferably H 2 SO 4 ). This aqueous phase may be evaporated to recover a copper salt or it may be electrolysed to recover copper.

Description

Methods for treating this currency-containing foam are already known. For example, it is possible to melt the iron and sulfur foam, for example in the form of pyrites, to form a crude melt containing a small amount of copper and copper, consisting of iron and copper with a small amount of lead. The lech is then processed in the converter, anodes are cast from the raw copper which are electrolytically refined, for example by a conventional method for copper refining. However, it is hardly economically feasible to provide a device for carrying out this process with respect to the zinc-lead furnace furnace, since the various copper produced in this process is relatively small.

The foam in the foam is likely to be captured in an elemnary form or as a compound, for example in the form of copper sulfides or arsenides, which are incorporated into the matrix of metal-rewarded lead. It was previously believed that it would be difficult to isolate this currency using conventional extraction agents.

British Patent No. 1,303,070 discloses a method for leaching copper from a foam comprising a dilute aqueous solution of sulfuric acid in the presence of a free oxygen-containing gas, whereby soluble sodium copper is recovered.

Further, a method of leaching copper from a foam comprising copper using an aqueous hmociacal solution is known.

Principle of a method for the isolation of copper from metallic materials, in particular from a foam containing copper obtained by pyrommallurgical raw lead, by leaching pulverized copper particles containing copper in the form of a metallic lead containing copper and copper compounds as inclusions with aqueous amoonacal solution to recover copper from the foam according to the invention consists in that the leaching solution content provádí.uvedeným amociakálním ^ bore formed below both the sulfate ions as uhličiaшlteé, wherein the leach solution comprises at least 15 g of ammonia per DTR in Reno ^^ like masses and ^N, OTA ^^ uáržuje in between 2 and ^{0 Z 100} ° C, the pH of the deposition solution at a value of at least 9.0 and the ratio mooární sulfate to the leaching solution in the range 1: 3 to 3: 1st

The leaching is preferably carried out in an oxidant stream. - gas, for example. air or oxygen. According to a further embodiment of the process according to the invention, the solution extracted from the leaching is additionally treated with an oxidizing gas in order to convert the ion exchangers into ions.

With the amociaal solution for leaching copper from the foam according to the invention, less impurities are extracted into the copper-enriched solution than in the known acid leaching process. In leaching, less iron, arsenic and antimony are transferred to the alkali solution, in particular, than to the acidic solution. Therefore, it is less difficult to purify the solution obtained by leaching because it is known that organic solvents of extran! the ammonia solution is preferably selectively compared to other elements such as iron, zinc and arsenic.

The aqueous solution of the leaching solution consists of an aqueous solution of sodium hydroxide and sodium hydroxide.

The leaching solution can be prepared by carbonating ammonia water with carbon dioxide, for example from a melting furnace.

The leach solution for the process of the present invention further comprises sulfate ions together with carbon ions. The molar ratio of carbon to sulfate in the leach solution is up to 1: 3. The presence of sulfate ions is believed to have the following advantages:

Reduction of the proportion of impurities, in particular lead and zinc, to copper in the leachate, reduction of the amount of copper losses in the filter cake after filtration of the residue - and lower partial. ammonia pressure over the leach solution.

The solution resulting from the leaching process after filtration is preferably contacted with an organic solvent, which is a specific extraction agent for the copper, to be transferred to the organic phase, from which the copper can then be extracted back into the aqueous solution by introducing the organic phase. Contact with an aqueous solution of a mineral acid such as dilute sulfuric acid or hydrochloric acid. Suitable organic extracting agents are commercially available and are described in the patent literature. These extracting agents can generally be referred to as hydroxyoximes.

The aqueous copper sulfate solution formed by contacting the organic solvent with dilute sulfuric acid can be utilized either in the production of crystalline copper sulfate by evaporation and crystallization or as an electrolyte for the preparation of cathodic copper by the electrolytic metal recovery process. In general, the sulphate produced in this way is comparable in terms of purity to the sulphate obtained from other sources. The leachate solution can either be boiled to form a precipitate of basic copper carbonate or sulphate or treated with a reducing agent to obtain a metallic copper, for example in the form of a powder.

The ammoniacal leaching solution is maintained in this manner at a temperature ^{of from 20} ° C to ¹⁰⁰ ° C and the pH of the solution is at least 9.0, in particular 9.5 to 10.5.

It is preferred that the overflowing foam is stirred vigorously during the infusion and is in contact with the oxygen-containing gas. The leach solution can be circulated to keep the foam in suspension. ’

Preferably, the foam is conditioned to a particle size of mm175 mm before carrying out the infusion.

The leaching solution contains at least 15 g of ammonia per liter, expressed as ammonia, preferably containing at least 5 g of ions per liter, since it has been found that the reaction proceeds more rapidly in the presence of a small ion.

The process can be carried out under various conditions. In this case, it is necessary to ensure perfect liquid-solid contact when dissolving copper from the foam and good contact of the oxygen-containing liquid and gas in order to achieve the longest dissolution of the copper in the exclusion solution. For this purpose, well-known methods suitable for continuous and continuous operation, for example efficient mixing in a tank by means of a high-speed turbine, inverting in a rotating vessel, fluidization or suspension circulation, are used. Alternatively, percolation may be used in which the liquid may flow through a pile or bed of foam in the form of grandiose. In this case, it is particularly preferred that the liquid contains a small amount of preformed amine ions in the form of an amine to dissolve the metal CCdd, since oxidation in the foam bed is possible to a small extent and that the amine containing ions are low. have been oxidized separately for recycling and for purification and extraction.

The concentrations of amoonac, dilution and sulphate are not critical. · With a lower content of these substances, the limitations will primarily be economic, as excessively dilute solutions require relatively large tanks and a large consumption of pumping energy. At higher concentrations, the known requirements and solubility and stability are given.

Pom ^ Try kmonnkku to ammonium salt are not decisive. Bravely dissolved copper is often in excess of the thio-ionic value for Cu / NH 4 / CO 2 cationic sodium citrate, for example from about 1 gram of copper to 1 mole of ammonium carbonate, 2 moles of 01O 2, and the limitation is ammonia together with. The ions in solution rather than ketone. At low proportions of ammonia, there is a tendency to precipitate a basic carbonate, while at higher proportions the solutions have unnecessarily high partial pressures, causing inefficient losses of ammonia by entrainment into the off-gas. Higher loadings also burden the extractant, reducing the amount of copper transferred to the extract and preventing the extractant from evaporating easily and in pure form.

Preferred molar ratios of ammonia to ammonium salts are 0.5 to 4.0 NH 4: 1.0 / NH 4 / gX, where X is a carbonate anion and / or sulfate anion, but a ratio of about 0.1 to 10 can be used: 1. The total free and combined ammonia content should be about 3.0 to 4.0 moles: 1 gram gram of copper to be dissolved, together with a suitable addition for evaporation and loss · The preferred copper content in the leaching waste liquid is 20 to 100 g / 1 with a suitable ratio of ammonia to ammonium salts, however, an effective operation of the process is possible with about 1 to 200 g of copper per liter.

The leaching solution may initially be copper-free, provided that there is sufficient oxygen present to dissolve the desired amount of copper, but it is preferred that the solution contains an amount of copper ions in the form of an amine that could then rapidly dissolve the metal currency according to Equation ++

CuCNH 3) (aqueous solution) + Cu (atom) -> Cu ₂ (? 3) 4 with subsequent or simultaneous oxidation. The raffinate from organic reagent extraction is never virtually free of copper, this criterion is achieved in a cyclic process. It should be noted that 1 gram amine amine ionic cup ion gives 2 gram amine ammonium ionic reaction after reaction without the need for oxidation in the leaching reactor, so it is desirable to feed the raffinate as a solution containing 50% of the desired copper concentration, the leachate effluent will have the desired specific ion content in the form of an amine, given by a sufficient amount of copper and adequate reactor reaction conditions. This solution can be oxidized separately, allowing freedom in designing the apparatus and in carrying out the process. The reaction temperature is usually about 20 ° C, but may range from 20 to 100 ° C, as determined by the design of the apparatus and the manner of execution. The preferred temperature range is 20 to 50 ° C.

The recovery of copper from the leaching waste solution is preferably carried out by solvent extraction, in particular by contacting the leaching waste solution with hydroxyoxime dissolved in kerosene. The extractant is diluted to a content of 1-40% by volume with an inert, substantially water-insoluble organic solvent, for example, high flash point kerosene. The extraction is carried out by contacting two liquid phases countercurrently in a known apparatus. The purpose is to substantially dissolve the currency in the organic phase in the form of a complex with the extraction agent and then to separate the two phases quickly and in pure form for subsequent processing.

The most commonly used device is a settler with a mixer, but it is also possible to use shower columns, packed columns, pulsed tray columns, rotary disc and centrifugal extraction devices. The number of extraction steps required is not critical. In the cyclic process, it is desirable to leave a small amount of copper in the raffinate, for example 5 to 10 g / l, in order to achieve a rapid dissolution of the copper. In this case, no complete extraction is performed and usually less steps are required than when a complete extraction is required. Often one or two steps is sufficient.

The enriched organic phase containing the copper and trace elements can be washed with a weak acid, for example an aqueous sulfuric acid solution at pH 2-5 to remove zinc and ammonia prior to stripping. Stripping is carried out by treating the enriched organic phase with a concentrated aqueous solution of an acid, in particular sulfuric acid, containing about 150 to 200 g of free acid per liter, in a similar apparatus to that used for extraction. Again, the number of stages required varies according to circumstances and is not critical. The first requirement is to reduce the copper content of the organic phase after stripping to a low, economically beneficial value, for example about 0.5 g / l, to achieve the maximum viable capacity of the organic phase for converting the copper to this phase. Dissolve about 0,4 g of copper or a proportional quantity for higher extractant concentrations in 1 liter of kerosene containing 10 ml of extraction agent.

The usual maximum concentration of said extractant is about 40 vol%, which is about 16 g of copper per liter. If 0.5 g / l remains in the organic phase after stripping, a conversion of 15.5 g of copper per liter is defined as the capacity for transfer of copper. The relative flow rates and the transfer of media from the leachate to raffinate effluent, from the enriched organic phase to the stripping phase, and from the stripping liquid to the recycled liquid must be proportional to the hmoonnoti of the copper transferred per unit time.

When leaching the currency from the foam obtained from the raw lead from the shaft furnace, the copper compounds usually require more environmental oxidation conditions to dissolve the currency from the materials used than that of the zinc and lead furnace lead. To achieve an acceptable dissolution rate of a production unit operating manual should be a higher pressure than the pressure kyssíku atmooférický and elevated temperatures, for example during the processing of these maaeeiálů The advantage Nu ^{d p} ^ j ^ (^ ^c ^ ^d ^ ^and LN and kysHku ^0.1 0 5 MPa and a temperature between approximately ⁰ and 3 ^{of the 100} ° C.

The invention is further elucidated with reference to the accompanying drawing, in which a scheme for carrying out a process for the isolation of copper from foams containing copper derived from pyromoealuric raw lead is shown.

The foam contains, adjusted to 3.175 mm particles, together with an aqueous solution of ammonia and ammonium, and with air is fed to the leach tank. The remainder of the leach tank J is discharged to a lead recovery device (not shown). The enriched liquid containing the dissolved copper compounds is passed to filter 1 and, after filtration, fed to a device 2 in which solvent extraction and raffinate and extract separation are carried out.

The raffinate separated from the organic phase in the plant 2 is recycled to the leaching stage, part of the raffinate is withdrawn and fed to the distillation plant J together with the steam and calcium oxide. The ammonia and carbon dioxide separated by de-distillation in the distillation apparatus are fed back to the leaching stage for optional treatment of the leaching solution. The de-distillation device J allows removal of debris such as zinc, nickel and arsenic from the leaching circuit. The slurry from the distillation apparatus J is film-coated with 3%, from which insoluble inorganic salts, such as zinc-nickel hydroxides and carbonates and calcium arsenate, are stripped.

The organic solvent-enriched organic phase obtained in the apparatus is sent to a scrubber apparatus where the copper compounds are transferred to an aqueous sulfuric acid solution and the separated organic phase is recycled to apparatus 2. The aqueous sulfuric acid solution containing the copper is passed to the tank unit 6, in which the electrolytic currency is recovered by deposition as a cathodic currency. The waste electrolyte from the unit 6, enriched in the sulfuric acid treatment, is recycled to the stripper. · The liquid removed from the filter% is discharged to the waste, while the removal of the off-line electrolyte is necessary to control the level of impurities.

The process according to the invention is further described in the examples.

Pi to Idl

Extraction of precious metals in the foams and preparation of basic cupric carbonate from the leaching effluent.

From a dry foam containing copper (118.8 g, 29.3 g Cu), a suspension of 4 moles of ammonium hydroxide, 2 moles of ammonium carbonate was prepared in an aqueous solution (500 µl) while air was introduced into the liquid at a rate of 1 liter per minute through frit. platičky. The temperature rose from LV ° ^C for ^{from 2.5} and ² h, then decreased at ² ° C for 1 ⁵ hours. ^The exhaust air was scrubbed with acid. Regular analyzes of leaching waste liquid and ammonia entrained in the exhaust air gave these results;

Time (h) 1 2 3 4 5 Copper concentration g / l 16 35 42 46 50 Average oxygen efficiency% 12 13 10 9 7 + Removed ammonia% 3.9 7.9 10.8 13.8 15.2 + Approximate extraction Copper% 25 56 68 73 80

+ Based on total ammonia, ammonium salt and copper supply ·

The cake (96.3 g, washed and dried at 100 ° C) and the dark blue ammonium carbonate solution (440 ml) were separated from the mixture by filtration, from which, after steam distillation,

Dark green cupric carbonate containing impurities (39,9 g, 52,5% Cu, washed and dried). The weight balance for the main elements is contained in the table below. Change Lead Zinc iron Foam containing% 24.67 57.9 3.66 3.54 Waste solution from leaching g / 1 49.1 0.795 3,975 0.1136 g% G % g% g « Washing liquid waste, solution from leaching 23.3 79.5 0.39 0.57 1.94 44.6 0.06 1.43 Washed and dried · the rest of the foam 6.0 20.5 68.4 99.43 2.41 55.4 4.15 98.57 The total amount of 29,3 100 68.79 100 ALIGN! 4.35 100 4,21 100 Coal precipitate čitan 20.9 0.35 - 1.75 0.05 Antimon Arsenic Silver Foam containing% 1.11 b74 0.146 Waste solution from leaching g / 1 0.318 2.27 0.0068 g « G % g %

Washing liquid, waste liquid

leaching 0.16 12.12 1.11 53.6 0.003 1 »73 Washed and dried. the rest of the foam 1.16 87.78 0.96 46.4 0.17 98.27 The total amount of 1.32 100 ALIGN! 2.07 100 ALIGN! 0.173 100 ALIGN! Coal precipitate čitan 0.14 - 1.0 - 0.003 -

Example 2

Influence of copper concentration on copper extraction rate from foam

The foam samples of 3.175 mm (20 g, 26.8 wt% Cu) were extracted in the conventional manner with air inlet (1 liter per minute) using amine carbonate solutions (500 mL) at room temperature. These solutions, containing various concentrations of copper, were prepared by mixing a carbonate solution such as an amine with Fitrtl, obtained by reacting the copper with a similar solution of an amine. The concentration of free ammonia was thus almost the same in all extractions and only the concentration of the ammonia was measured. The results show that the currency remaining in the refinery fed back to the leaching significantly influences the rate of dissolution of the copper from the foam.

Time (min) 0 5 15 Dec 30 90 Copper content of initial solution g / l Temperature (° C) 14.5 16.1 17.6 19.7 19.4 Me3 in solution (g / l) 0 1,21 4.52 8.55 10.70 0 Kjunml. increase (g / l) 0 1,21 4.52 8.55 10.70 Temperature ⁽ ° ^C) 18.8 20.5 22.8 22.3 19.8 Me3 in solution (g / l) 6.57 9.66 13.60 16.40 17.15 6.57 Kumuu. increase (g / l) 0 3.09 7.03 9.83 10.55 ^T ep.lota ⁽ ° ^C) 18.8 20.5 22.8 22.3 19.8 Me3 in solution (g / l) 9.24 13.06 17.08 18.77 20.08 9.24 Kunuu. increase (g / l) 0 3.82 7.84 9.53 10.84 Temperature (° C) 21.6 23.7 23.7 21.8 20.3 Me3 in solution (g / l) 12.52 16.86 20.7 22.10 23.26 12.52 Kum !. increase (g / l) 0 4.34 8.19 9.58 10.74 The table shows that at least 5 g of copper per liter in elimination solution considerably faster

is leaching.

Example 3

Complete leaching, organic reagent extraction, stripping and electrolysis

Five cycles were performed.

Extraction

Foam hangs! Me 3 (3.175 mm, 26.8% Cu, 20 g) was leached in recycled amine (100 mL) with aeration (1 liter per minute) for 80 to 120 minutes. If necessary, the solution was treated by adding ammonia and carbon dioxide. About 10% >% of the copper remained in the residue, 80 to 84% was recovered in the clear filament, about 9% was pulled to the residue and had to be removed by purging. The raffinate had to be purged with light petroleum in the last cycles to remove the entrained extraction agent which would cause foaming upon leaching.

Extraction into organic phase

The filtrate in each cycle (80 ml) was extracted with a 6x80 ml solution of the above extraction agent (30% concentration) to transfer all the copper to the organic phase. The extractant solutions were stored in separating funnels numbered 1 to 6. and the next cycle, the extractant solutions were washed sequentially with water (6 x80 mL), proceeding from the shaker settler # 1 to remove ammonia entrained in the extractant solution.

Stripping into aqueous phase

This process was carried out with an artificially prepared waste electrolyte (30 grams) (1 180 grams sulfuric acid per liter) so that the electrolyte was shaken with the above extraction agent solution 6 x 80 ml, starting from shaker settler no. 6 к nr. 1 · Electrolyte from the electrolysis stage was used in the following stripping cycles. The enriched electrolyte was foamed with air or washed with kerosene prior to electrolysis to remove traces of entrained extraction agent that would interfere with copper deposition.

Electrolytic deposition

Electrolysis was performed on a standard platinum electrode copper analysis apparatus to produce shiny, smooth and even deposits from the enriched electrolyte, which was foamed prior to electrolysis, but formed from an electrolyte that had previously been washed only with kerosene, uneven and nitric acid. Bye

uneven deposition · Μδδ was finally stripped of the mentioned procedures are

The results are summarized in the table

Solution cycle number Cu g / 1 Solution volume, ml Ni As Pb Zn Fe Coll Amin 2 2.4 6.1 0,023 1.3 0,02 78 Raffinate 5 2.6 7.5 0,023 1.3 0,02 78,5 Waste 1 29.6 0.03 0.01 0.02 0,023 0.08 450 electrolyte 3 28.1 0.05 0.01 0.11 0,039 0.04 466 5 30.0 0.03 0.01 0.16 0,047 0.04 459 Katodická 1 41.9 <0.01 <0.01 <0.01 <0.007 0.03 100 ALIGN! mě3 x 3 40.4 <0.01 <0.01 <0.01 <0.007 0.04 100 ALIGN! 5 30.8 <0.01 0.01 0.01 <0.007 <0.03 100 ALIGN!

x after dissolution in aqueous nitric acid.

The behavior of the impurity elements is briefly described below.

Lead: largely remains as a metal or carbonated residue, but accompanies the currency into the extraction solution.

Arsenic: is present in the raffinate up to a content of 2.5 to 3 g / l, largely remains in the copper extraction and the remainder is discarded into the remainder of the foam.

Nickel: is in raffinate, probably accompanies me3 during the process.

Zinc: in the raffinate up to a content of about 7 to 10 g / l, the remainder being discarded into the remainder of the foam, but a small amount accompanies the process

Iron: trace amounts go through the process, most are discarded into the rest of the foam.

Antimony: largely disposed of in the rest of the foam, but a small amount accompanies me3 in the process ·

Influence of sulphate on leaching

The following leaching experiments were carried out in a spherical flask equipped with a paddle stirrer, air inlet through a frit plate, a thermometer. The gas was sent to a scrubber with a sulfuric acid solution using a water-cooled reflux condenser.

The foam contained 29.3% copper and was sized for particle size. 3,175 mm. Aqueous solutions containing a mixture of ammonia and ammonium carbonate and / or ammonium sulfate were prepared by adding to a 2 molar ammonium hydroxide solution:

(a) 1 mol (^И ^ СОз

b) 0.75 moles (NH4Cl2, 0.251 moles) (Ni2SO4)

c) 0.5 moles (№4) ^ 3, 0.5 moles (№4) 2804

d) 0.25 mol (N 2 O 3 CC 4, 0.75 mole (3 O 3 SC 3))

(e) 1 mol (№4 ^ 04

The flask was filled with a suitable solution (1 liter) at about 20 ° C. With efficient stirring, 200 g of foam containing foam was added, then the flask was sealed and air was bubbled through the liquid at a rate of 1 liter / min. The copper dissolved at the beginning quite rapidly and the reaction lasted for two hours except as otherwise prescribed. The temperature rose spontaneously to about 40 ° C, only when no carbonate was present, the copper dissolution was so slow that the exothermic reaction was much less pronounced.

The foam-containing suspension and the effluent were filmed under standard conditions and the clear liquid was subjected to shaking with shaking solvent (25 vol.%) Until all of the swab was transferred to the organic phase. The organic phase is then stripped with an aqueous sulfuric acid solution (180 g / l) to obtain an acidic solution containing cupric sulphate and an organic phase suitable for recycling. after adjusting losses.

The results of the experiments are compiled in the tables.

A. Composition of leach solution and waste liquor

Waste liquid from leaching 2 moles NH4OH, 1 mol (Ν ^^ Κ (Х = СОз and / or SOO)

pH Cu ⁽¹ ) Cu Pb Zn g / 1 Filter cake (4) humidity% Withdrawn ammonia% <5) Initial Finally Fe Ni Coll As and 10.15 11.25 85 50.6 0.27 3.9 <0.01 0.07 0.4 1.6 7.1 7.8 b 10.15 10.80 81 47.9 0.23 4.4 0,039 0.07 0.6 1,2 4.3 6.5 c 10.15 10.50 77 ^{1 (2) 3 4 5} 46.1 0.13 4.4 0,078 0.07 0.6 0.8 2.8 5.4 d 10.10 10.10 81 47.8 0.05 4.0 0,023 0.07 0.5 0.4 1.9 5.7 e 10.05 9.75 26 mm (3) 15.5 0.15 4.4 <0.01 0.02 <0.1 <0.01 3.3 5.3

(1) Copper in the leach effluent, including the flour cake wash liquid, as a percentage of copper in the treated foam.

(2) Time, reaction 100 minutes.

(3) Reaction time 6 hours.

(4) Volume of entrained liquid, as a percentage of total leachate waste liquid.

(5) Ammoniac entrained in the extract air, based on the total quantity! ammonia and ammonium salts.

B. Proportions of elements as impurities extracted from amine leaching effluent, based on the hmoonoot copper unit

Set 1 Cu Pb Zn Fe Ni Coll As and 1.0 0,0022 0,0091 <0.0002 0.001 0.0011 0,002 b 1.0 0,0033 0.030 0.0008 0,0014 0,0023 Ό C 1.0 0.0028 0.019 0.0017 0,0012 0.0035 -0 d 1.0 0,0010 0.0176 0.0005 0,0014 0,0033 0,002 ' e. 1.0 0.0097 0,098 <0.0006 -0.001 <0.006 ~ 0

From this, there are some advantages when using a mixture of silica and sulphate for leaching copper from the foam and some drawbacks, if only sulphate anions are present:

1. Maintains a high reaction rate of a system containing only anion (at least about 75 mole% of sulphate and 25 mole% of anion). The rate is very low when only sulphate is present.

2. The leaching effluent dissolves gradually to less arsenic, antimony and lead as the sulfate content increases. A large amount of lead can be dissolved if only sulphate is present.

3. The remainder of the foam (when using only Unlicia to leach approximately half of the very fine, slowly sedimenting and filtering material) is not progressively coarser, it is easily! and it retains less waste liquid in the fit cake as the sulfate content increases.

4. As the sulphate content increases, the losses of ammonia by entrainment of the exhaust air are gradually increased.

5. With extraction with a copper-specific reagent, the copper to copper ratio is constantly reduced as the sulphate content of the liquid from the liquor increases, but then at

100% of the sulfate content in the liquid increases sharply. Tt is particularly important since the lead converted dt of these extractants is removed at the acid treatment stage. P ^ u ^ U ^ j is ^ e]. with sulfuric acid, much lead sulphate is formed as a precipitate which accumulates at the interface between the extraction solution and the acid, thereby increasing the formation of an impure precipitate, making it difficult. separation in pure form and complete recovery of the expensive extracting agent. The residue is dissolved in a sulfuric acid solution, which is to prevent contamination of cathodic copper or copper salts.

Claims (11)

SUBJECT OF THE INVENTION CLAIMS 1. A process for the isolation of copper from metallic materials, in particular from copper-containing foam obtained from pyrtmetallurgical raw lead, by leaching the crushed, foam-reinforcing foam particles. in the form of a lead metal matrix containing copper and copper compounds as the inks, an aqueous solution for recovering copper from the foam, which does not impede the leaching with said amoqual solution. obsahuUícím hereinafter as sulfate and UΙηΐΐϋ ηο ^ ^ ions, wherein the leach solution comprises at least 15 g of ammonia per liter expressed as amoonak temperature of ulová'lí ^yl maintained in the range of ²⁰ 'to ¹⁰⁰ ° C, a pH in the ^y lu ^{h ¹H} TOAC a solution with a pH of 9.0 and an ootate ratio of sulphate to potassium in the leaching solution ranging from 1: 3 to 3: 1. 2. The method according to claim 1, characterized in that the leaching is carried out at a flow rate of the oxidizing gas. 1 1 3. The method of claim 1 wherein the leachate solution is treated with an oxidizing gas to convert the monovalent copper ions to the divalent copper ions. 4. The process of claims 1 to 3, wherein the leachate solution is treated with a copper-selective organic solvent to convert the copper into the organic phase. 5. The process of claim 4, wherein the organic phase is treated with an aqueous mineral acid solution to convert the copper back into the aqueous solution. 6. A process according to claim 5, wherein the aqueous solution is evaporated to crystallize the copper salt. 7. The process of claim 5, wherein the aqueous solution is subjected to electrolysis to precipitate metallic copper at the cathode. 8. The process of claim 5, wherein the organic phase is treated with dilute sulfuric acid, whereupon the aqueous solution is evaporated to crystallize cupric sulfate from the sulfate solution. 9. The process of claim 5, wherein the organic phase is treated with dilute sulfuric acid, after which the aqueous solution is subjected to electrolysis to precipitate copper at the cathode from the sulfate solution. 10. A process according to any one of claims 1 to 3, wherein ammonia is expelled from the solution to be extracted from the leachate to obtain a precipitate of the copper salt in solid form. 11. A process according to claims 1 to 3, characterized in that the copper compounds contained in the leachate solution are treated with a reducing agent for their regeneration in the form of a metal, for example copper powder.