RU2373296C2 - Method of extracting non-ferrous metals from water solutions of their salts - Google Patents

Abstract

FIELD: metallurgy industry. ^ SUBSTANCE: invention refers to method of extracting non-ferrous metals from water solutions of their salts, and can be used both for cleaning of spent solutions of chemical or galvanic nickel coating from nickel, cobalt, molybdenum, tungsten, vanadium and bismuth ions, and for extracting those metals from other solutions of industrial production, as well as for manufacturing powders of the above metals or their suspensions. Method involves extraction of non-ferrous metals from water solutions containing sodium hypophosphite and nickel ions by bringing the ratio of mole concentrations of ions of nickel and sodium hypophosphite up to the value more than 1:1, and content of nickel ions in the solution - up to the value of 5-2 g/l. The conditions are created, which contribute to reduction of ions of non-ferrous metals in the solution to free metals by introducing ammonium hydroxide to the solution till pH solution equal to 7.8-8.3 is obtained. Then sodium hydroxide is added to the solution till concentration is 150-400 g/l, and solution is kept at room temperature during 12-15 hours with formation of non-ferrous metals deposit which is separated by filtration. Then phosphorus is removed from the solution. ^ EFFECT: increasing degree of removing non-ferrous metal from solution. ^ 2 cl, 13 ex

Description

The present invention relates to methods for the extraction of metals from ores or concentrates by wet chemical methods and can be used both for the purification of spent solutions of chemical or galvanic nickel from nickel, cobalt, molybdenum, tungsten, vanadium, bismuth ions, and for the extraction of these metals from other solutions industrial production, as well as for the manufacture of powders of these metals or their suspensions using chemical processes. The purpose of this method is to increase the degree of extraction of these metals from solutions of their salts.

A known method for the extraction of Nickel from aqueous solutions, described in the patent of the Russian Federation No. 2186136 (MKI ⁷ C22B 23/00, publ. 2002.07.27). In accordance with this method, CYANEX 272 is used as a reagent for nickel extraction, the active component of which is di (2,4,4-trimethylpentyl) phosphinic acid. In this case, nickel extraction is carried out by extraction using the CYANEX 272 6 extractant at pH <10 and controlling the pH during the extraction process, and direct extraction is carried out by precipitation of nickel in the composition of the organophosphorus compound at pH 10.

The extractant CYANEX 272 used in this method ensures the extraction of a metal salt from the solution to a low degree, since metal extraction is carried out not by binding it by the formation of a new compound, but due to the higher affinity of the salt of this metal to the extractant, as to the solvent of this salt. For this reason, the degree of extraction of metal from a solution of its salt is not high enough.

There is also a method of extracting Nickel from spent alkaline solutions of chemical nickel, described in the patent of the Russian Federation No. 2023034 (MKI ⁵ C22B 20/00, publ. 1994.11.15). In accordance with this method, an ammonia-carbonate solution containing nickel is heated to 70-80 ° C, sulfur solution in an aqueous solution of sodium hydroxide or ammonia is added to it with stirring, then ammonia is distilled off at 80 ° C to its residual concentration in solution 50 -65 g / l and the precipitate containing nickel is separated by filtration.

In this method, nickel is isolated from the solution by reducing it to a metal powder, which is insoluble in water and precipitates, and the precipitate is filtered off. In this case, the recovery occurs due to the restoring properties of sulfur (S °), which is introduced into the solution. To enhance the recovery process, the entire solution is heated. However, sulfur (S °) has a not very high reduction ability, therefore, even when heated, nickel in solution is not completely restored and, naturally, not all of it is released from the solution.

The closest known method is the extraction of nickel from spent acidic solutions of chemical nickel deposition described in RF patent No. 2166552 (MKI ⁷ C23B 23/44, publ. 2001.05.10). In accordance with this method, 1: 1 finely dispersed nickel powder and then dry sodium carbonate are introduced into the spent acid solution of chemical nickel plating containing hypophosphate sodium in a molar ratio to nickel ions of 1: 1. In this case, sodium carbonate is introduced into the solution in small portions at a temperature of 55-65 ° C, at a pH of 6-7.

In the known method, the reducing activity of sodium hypophosphite is increased by introducing finely divided nickel powder into the solution, which under the conditions created by the introduction of sodium carbonate and maintaining the set temperature and pH of the medium acts as a catalyst for nickel reduction. Nevertheless, it should be noted that in this case too, the reducing activity of sodium hypophosphite does not increase very much, therefore, nickel release from the solution in this case also does not occur fully.

The objective of this invention is to create in an aqueous solution of non-ferrous metals such conditions under which the process of recovery of non-ferrous metal ions, in particular nickel or cobalt, or molybdenum, or tungsten, or vanadium, or bismuth, will be significantly enhanced, as a result of which the degree of conversion of these ions into a metal, i.e. in insoluble form will also be greatly increased. As a result of this, the degree of release of non-ferrous metal from the solution will also be significantly increased.

The problem is solved in that, as in the known, in the proposed method for the extraction of non-ferrous metals, in particular nickel, cobalt, molybdenum, tungsten, vanadium and bismuth from an aqueous solution containing a salt of these metals. pre-determine the content of nickel ions and sodium hypophosphite in this solution, after which the ratio of the molar concentrations of nickel ions in the solution and sodium hypophosphite is adjusted to a value of more than 1: 1 and conditions are created in the solution that contribute to the restoration of non-ferrous metal ions in the solution to a neutral metal, and the precipitate of non-ferrous metals is separated by filtration.

In contrast to the known concentration of nickel ions in the solution is adjusted to a value of 5-2 g / l, and to create conditions in the solution that contribute to the recovery of non-ferrous metal ions in the solution to metal, ammonium hydroxide is introduced into the solution in an amount at which the pH of the solution becomes equal to 7.8-8.3, then sodium hydroxide is introduced into the solution in an amount at which its concentration becomes equal to 150-400 g / l, after which the solution is kept at room temperature for 12-15 hours.

It is advisable to add alkali, for example NaOH, to the solution remaining after the extraction of non-ferrous metals, and bring the pH of the solution to a value of at least 11, after which iron trichloride should be added to the same solution in an amount exceeding the molar concentration of sodium hypophosphite contained in this solution at least 2 times. After carrying out these operations, a precipitate of iron phosphite precipitates from the solution and the solution is thus purified from phosphorus compounds.

,

, Fe²⁺, Bi³⁺,

, и Sn²⁺ в присутствии ионов Bi³⁺ происходит восстановление и соосаждение металлов, входящих в указанный выше перечень. Кроме того, совместно с никелем соосаждаются также ионы Cu²⁺, Ag⁺, Sb³⁺, Pb²⁺, In³⁺, Cd²⁺, Ga³⁺, Zn²⁺ при заданном соотношении Ni - металл, обусловленном электродными потенциалами этих металлов. В соответствии с вышесказанным, извлечение цветных металлов из водных растворов их солей осуществляется, прежде всего, из никельсодержащих растворов. Поэтому в раствор, из которого извлекаются цветные металлы, обязательно должна быть введена растворимая соль никеля. При этом общий процесс восстановления ионов цветных металлов в растворе основывается на следующих более простых процессах. Во-первых, осуществляется разрушение всех образовавшихся в растворе комплексов никеля и создание в этом же растворе стабильных аммиакатных комплексов. Это обеспечивается введением в раствор гидроокиси аммония - NH₄OH в количестве, при котором pH раствора станет равной 7,8-8,3. Затем осуществляется разрушение аммиакатных комплексов никеля, для чего в раствор вводится гидроксид натрия - NaOH -, в количестве 150-400 г/л или 4-10 моль/л. При этом авторами было впервые установлено, что в сильнощелочной среде в присутствии гидроксида натрия аммиакатные комплексы никеля разрушаются с появлением свободных ионов никеля. Свободные же ионы никеля взаимодействуют с восстановителем с образованием гипофосфита никеля. Одновременно происходит гидролиз свободного гипофосфита натрия и образование активного водорода, который взаимодействует с гидроксил ионами с появлением свободного электрона. Гидролиз гипофосфита никеля и наличие свободного электрона приводит к зародышеобразованию металлического никеля в объеме раствора. Дальнейший рост кристаллитов никеля протекает по механизму автокаталитической реакции. Размер кристаллита никеля определяется концентрацией остаточного никеля в растворе. При выдержке раствора в течение 10-12 часов кристаллиты никеля восстанавливают практически все ионы никеля из раствора. Количество остаточного никеля в растворе составляет 0,05-0,1% от исходной концентрации.It is known that the extraction of non-ferrous metals from aqueous solutions of their salts is carried out by restoring the ions of these metals contained in the solution to powder metal particles. Moreover, when carrying out the reduction reaction, in addition to reducing agents, other substances are added to the solution, which are, for example, part of the buffer mixtures or are stabilizers. In this case, the non-ferrous metal ions contained in the aqueous solution, which are part of the soluble salt, react with these substances in the presence of a reducing agent to form new compounds, including complex ones, in which non-ferrous metal ions do not react with the reducing agent and, as a result, are not reduced. Given these processes, the inventors have developed and first implemented a process for the recovery of non-ferrous metal ions from solutions of their salts, based on the fact that in a nickel-containing solution during the separation of nickel ions from it by reducing them to a powder metal, followed by its precipitation, if there is any Co ²⁺ ion solution,

,

, Fe ²⁺ , Bi ³⁺ ,

, and Sn ²⁺ in the presence of Bi ³⁺ ions the reduction and coprecipitation of metals included in the above list occurs. In addition, Cu ²⁺ , Ag ⁺ , Sb ³⁺ , Pb ²⁺ , In ³⁺ , Cd ²⁺ , Ga ³⁺ , Zn ²⁺ ions also co-precipitate with nickel at a given Ni - metal ratio due to the electrode potentials of these ^ions. metals. In accordance with the foregoing, the extraction of non-ferrous metals from aqueous solutions of their salts is carried out, first of all, from nickel-containing solutions. Therefore, a soluble nickel salt must be added to the solution from which the non-ferrous metals are extracted. Moreover, the general process of reduction of non-ferrous metal ions in solution is based on the following simpler processes. Firstly, all nickel complexes formed in the solution are destroyed and stable ammonia complexes are created in the same solution. This is ensured by introducing into the solution ammonium hydroxide - NH ₄ OH in an amount at which the pH of the solution becomes 7.8-8.3. Then, the ammonia complexes of nickel are destroyed, for which sodium hydroxide - NaOH - is introduced into the solution, in an amount of 150-400 g / l or 4-10 mol / l. Moreover, the authors found for the first time that in a highly alkaline medium in the presence of sodium hydroxide, ammonia complexes of nickel are destroyed with the appearance of free nickel ions. Free nickel ions interact with the reducing agent to form nickel hypophosphite. At the same time, hydrolysis of free sodium hypophosphite and the formation of active hydrogen occur, which interacts with hydroxyl ions with the appearance of a free electron. Hydrolysis of nickel hypophosphite and the presence of a free electron leads to nucleation of metallic nickel in the bulk of the solution. Further growth of nickel crystallites proceeds according to the autocatalytic reaction mechanism. The size of the nickel crystallite is determined by the concentration of residual nickel in the solution. When the solution is kept for 10-12 hours, nickel crystallites recover almost all nickel ions from the solution. The amount of residual nickel in the solution is 0.05-0.1% of the initial concentration.

Isolation of other non-ferrous metals ions — Co, V, Mo, Fe, Bi, W, Sn — from the solution occurs due to their coprecipitation with nickel, as shown in the examples.

The implementation of this method in existing at the filing date of the application industrial conditions is confirmed by examples.

Example 1

The object of the study is a chemical nickel plating solution prepared according to GOST 9.305-84 and containing nickel sulfate (25 g / dm ³ ), sodium hypophosphite (25 g / dm ³ ), sodium acetic acid (15 g / dm ³ ), and aminoacetic acid (20 g / dm ³ ), lead (II) sulfide (0.050 g / dm3). The nickel concentration in the spent chemical nickel plating solution is 4038.0 mg / L. An aqueous ammonia solution is added to 100 ml of the solution to pH = 7.8-8.3 and 28.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metallic nickel begins. The reaction time is about 12 hours. The concentration of nickel in the solution decreases to 26.30 mg / L. Nickel concentration is determined by photocolorimetry.

Example 2

The object of the study is a chemical nickel plating solution prepared in accordance with GOST 9.305-84, map 32 containing nickel sulfate (25 g / dm ³ ), sodium hypophosphite (20 g / dm ³ ), thiourea (0.001 g / dm ³ ), boric acid ( 15 g / dm ³ ). lactic acid (45 g / dm ³ ). The nickel concentration in the spent chemical nickel plating solution is 4038.0 mg / L. An aqueous ammonia solution is added to 100 ml of the solution to pH = 7.8-8.3 and 38.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metallic nickel begins. The reaction time is about 12 hours. The concentration of nickel in the solution decreases to 1.54 mg / L. Nickel concentration is determined by photocolorimetry.

Example 3

The object of the study is a chemical nickel plating solution prepared in accordance with GOST 9.305-84, map 32, consisting of nickel sulfate (30 g / dm ³ ). sodium hypophosphite (20 g / dm ³ ), ammonium chloride (45 g / dm ³ ), sodium citric acid trisubstituted (45 g / dm ³ ). The nickel concentration in the spent chemical nickel plating solution is 4710.0 mg / L. An aqueous ammonia solution is added to 100 ml of the solution to pH = 7.8-8.3 and 16.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metallic nickel begins. The reaction time is about 12 hours. The concentration of nickel in the solution decreases to 2.38 mg / L. Nickel concentration is determined by photocolorimetry.

Example 4

The object of the study is a chemical nickel plating solution prepared in accordance with GOST 9.305-84, map 32, consisting of nickel sulfate (25 g / dm ³ ), sodium hypophosphite (20 g / dm ³ ), sodium acetate (13 g / dm3), thiourea ( 0.002 g / dm ³ ), acetic acid (8 g / dm ³ ). The nickel concentration in the spent chemical nickel plating solution is 4038.0 mg / L. An aqueous ammonia solution is added to 100 ml of the solution to pH = 7.8-8.3 and 36.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metallic nickel begins. The reaction time is about 12 hours. The concentration of nickel in the solution decreases to 1.20 mg / L. Nickel concentration is determined by photocolorimetry.

Example 5

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a nickel sulfate concentration of 3140.7 mg / l. 4.2 g of sodium hypophosphite are dissolved in 100 ml of the obtained, after which an aqueous solution of ammonia is added to pH = 7.8-8.3 and 20.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metallic nickel begins. The reaction time is about 1 hour. The concentration of nickel in the solution decreases to 18.20 mg / L.

For the coprecipitation of metals, a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, map 35, consisting of nickel sulfuric acid (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ^{3) was used} ) The spent galvanic nickel plating solution was diluted with deionized water to a concentration of 3140.7 mg / L, sodium hypophosphite reducing agent was added, Co, Pe, Mo, V, Bi metal salts were dissolved in this solution and the solution was subjected to two-stage leaching.

Example 6

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a nickel sulfate concentration of 3140.7 mg / l. 4.2 g of hypophosphite, sodium are dissolved in 100 ml of the resulting solution, after which 10, 20, 40% Co is introduced into the resulting solution in the form of cobalt of 6-aqueous chloride and then aqueous ammonia is added to a solution pH of 7.8-8.3 and 20.0 g of sodium hydroxide. Under these conditions, the formation of precipitation containing Ni and Co. The reaction time is about 1 hour.

The presence of Co ^{2+ ions} in a purified solution is determined by conducting a qualitative reaction of cobalt ions with thiocyanate ions. Co ²⁺ cations in a weakly acidic medium react with thiocyanate ions NCS ^- to form a blue complex - tetratiotsianatokobaltat (II) ^{-ion: Co 2+ + 4NCS - ↔ [} Co (NCS) _4] ^2+. 2-3 drops of the analyzed solution are added to the test tube, a few drops of hydrochloric acid are added to pH = 5-6.8-10 drops of a saturated solution of potassium thiocyanate and 5-6 drops of an organic solvent (isoamyl ether) and the mixture is shaken. Blue color of the upper organic layer is not observed, which indicates the absence of Co ^{2+ ions} in the solution.

Example 7

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). This solution is diluted with deionized water to a nickel concentration of 3140.7 mg / l. 4.2 g of sodium hypophosphite are dissolved in 100 ml of the resulting solution, then 10, 20, 40% V in the form of ammonium metavanadate is introduced into the solution, after which aqueous ammonia is added to a solution pH of 7.8-8.3 and 20.0 g sodium hydroxide. Under these conditions, precipitation occurs, metallic nickel and vanadium. The reaction time is about 1 hour.

в очищенном растворе определяют действием перекиси водорода. В присутствии ионов

вследствие образования надванадиевой кислоты появляется красно-розовая окраска:The presence of ions

in a purified solution is determined by the action of hydrogen peroxide. In the presence of ions

due to the formation of nadvanadic acid, a red-pink color appears:

.

.

в растворе.On a porcelain plate, a drop of the analyzed solution is mixed with a drop of sulfuric acid, and a minute later a drop of hydrogen peroxide is added. No discolouration indicates no ions

in solution.

Example 8

The object of the study is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, map 35 containing nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent solution is diluted with deionized water to a nickel sulfate concentration of 3140.7 mg / L, and then 4.2 g of sodium hypophosphite are dissolved in 100 ml of this solution. 10, 20, 40% Mo is introduced into the resulting solution in the form of ammonium molybdenum acid, an aqueous ammonia solution is added to a solution pH of 7.8-8.3 and 20.0 g of sodium hydroxide. Under these conditions, a precipitate is formed containing metallic nickel and molybdenum, and the deposition rate has a parabolic dependence on the concentration of molybdenum. The reaction time is about 1 hour.

в очищенном растворе определяют посредством проведения качественной реакции ионов

с гидрофосфатами. Ионы

в присутствии гидрофостфат-ионов в азотнокислой среде образуют желтый кристаллический осадок фосфоромолибдата аммония: 12(NH₄)₂MoO₄+Na₂HPO₄+23HNO₃→(NH₄)₃H₄[P(Mo₂O₇)₆]↓+2NaNO₃+10H₂O+21NH₄NO₃.The presence of ions

in a purified solution is determined by conducting a qualitative reaction of ions

with hydrophosphates. Jonah

in the presence of hydrophosphate ions in a nitric acid medium, a yellow crystalline precipitate of ammonium phosphoromolybdate forms: 12 (NH ₄ ) ₂ MoO ₄ + Na ₂ HPO ₄ + 23HNO ₃ → (NH ₄ ) ₃ H ₄ [P (Mo ₂ O ₇ ) ₆ ] ↓ + 2NaNO ₃ + 10H ₂ O + 21NH ₄ NO ₃ .

.3-4 drops of the analyzed solution are placed in a test tube, a few drops of hydrochloric acid are added to pH = 7, 5-6 drops of nitric acid and 2-3 drops of sodium hydrogen phosphate solution are added. The contents of the tubes are shaken. No precipitation is observed, which indicates the absence of ions in the solution

.

Example 9

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a nickel sulfate concentration of 3140.7 mg / l. 4.2 g of sodium hypophosphite are dissolved in 100 ml of the resulting solution, and then 10, 20, 30, 40% Fe is introduced into it in the form of iron (II) 7-aqueous sulfate, after which aqueous ammonia is added until the pH of the solution is 7.8- 8.3 and 20.0 g of sodium hydroxide. Under these conditions, at an iron concentration of 10-30%, a precipitate forms. The reaction time is about 1 hour.

The presence of Fe ^{2+ ions} in the purified solution is determined by conducting a qualitative reaction of iron (II) ions with potassium hexacyanoferrate (III). In the presence of iron (II) ions, a dark blue precipitate or a blue solution of Turnbull blue is formed: 3Fe ²⁺ +2 [Fe (CN) ₆ ] ^3- = Fe ₃ [Fe (CN) ₆ ] ₂ ↓. 1 ml of the analyzed solution is placed in a test tube, 0.5 ml of a 2N hydrochloric acid solution is added, then 5 -6 drops of a solution of potassium hexacyanoferrate (III) are shaken. The absence of blue staining and precipitation indicates the absence of iron (II) ions in the solution.

Example 10

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a concentration of 3140.7 mg / L, in which 100 g of which 4.2 g of sodium hypophosphite are dissolved. 5, 10, 15, 20% Fe is introduced into the resulting solution in the form of iron (II) 7-aqueous sulfate and cobalt (Co) in the form of 6-aqueous cobalt with a molar ratio of iron (II) sulfate 7-aqueous: cobalt 6 -aqueous equal to 1: 1, add an aqueous solution of ammonia to a solution pH of 7.8-8.3 and 20.0 g of sodium hydroxide. Under these conditions, precipitation occurs, containing metallic nickel, cobalt and iron. The reaction time is about 1 hour.

The presence of Fe ²⁺ and Co ^{2+ ions} in the purified solution is determined by carrying out the qualitative reactions described in examples 7 and 10.

Example 11

The object of study is a solution of galvanic nickel plating. prepared according to GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a concentration of 3140.7 mg / L, in which 100 g of which 4.2 g of sodium hypophosphite are dissolved. 10, 20, 40% Bi in the form of bismuth (III) 3-aqueous sulfate in terms of metallic nickel is introduced into the resulting solution, an aqueous ammonia solution is added to a pH of 7.8–8.3 and 20.0 g of sodium hydroxide. Under these conditions, precipitation occurs. The reaction time is 30 minutes.

The presence of Bi ³⁺ ions in the purified solution is determined by conducting a qualitative reaction with iodides. When iodide solutions are added to hydrochloric acid solutions of Bi (III), a black precipitate of bismuth iodide is soluble in excess of the reagent to form a yellow-orange solution containing tetraiodovismuthate (III) ions: [BiCl ₆ ] ^3- + 3I ^- → BiI ₃ + 6Cl ^-

BiI ₃ + I ^- = [BiI ₄ ] ^- .

5 drops of the analyzed solution are added to the test tube, 10 drops of hydrochloric acid are added and a solution of potassium iodide is added dropwise. No precipitate was observed, which indicates the absence of bismuth ions in the solution.

Example 12

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution is diluted with deionized water to a concentration of 3140.7 mg / L, in which 100 g of which 4.2 g of sodium hypophosphite are dissolved. 10, 20, 40% Bi is introduced into the resulting solution in the form of bismuth (III) 3-hydrous sulfate in terms of metallic nickel and Sn in the form of tin dichloride 2-aqueous with a molar ratio of bismuth (III) sulphate 3-aqueous: tin dichloride 2 -aqueous equal to 1: 1, add an aqueous solution of ammonia to a pH of a solution of 7.8-8.3 and 20.0 g of sodium hydroxide. Under these conditions, rapid precipitation of black sediments containing metallic nickel, bismuth and tin occurs. The reaction time is 10 minutes.

Solutions purified from nickel ions and metal ions were purified from phosphorus compounds by adding a solution of ferric trichloride.

Example 13

The object of research is a galvanic nickel plating solution prepared in accordance with GOST 9.305-84, card 35, consisting of nickel sulfate (200 g / dm ³ ), sodium chloride (15 g / dm ³ ), boric acid (30 g / dm ³ ). The spent galvanic nickel plating solution was diluted with deionized water to a nickel sulfate concentration of 3140.7 mg / l. Then, 4.2 g of sodium hypophosphite were dissolved in 100 ml of the resulting solution, and aqueous ammonia was added to pH = 7.8–8.3 and 20.0 g of sodium hydroxide. Under these conditions, the formation of finely divided metal begins. The reaction time is about 1 hour. Then the solution is separated from the precipitation by filtration. To the resulting solution was added iron trichloride in a molar ratio of sodium phosphite: iron trichloride, equal to 2: 1. Under these conditions, precipitation of iron phosphite occurs.

Claims (2)

1. The method of extraction of non-ferrous metals from aqueous solutions of their salts containing sodium hypophosphite and nickel ions, characterized in that the ratio of molar concentrations of nickel ions and sodium hypophosphite to a value greater than 1: 1, the concentration of nickel ions in the solution to a value of 5- 2 g / l and create conditions conducive to the recovery of non-ferrous metal ions in the solution to free metals by introducing ammonium hydroxide into the solution to a pH of 7.8-8.3, followed by the introduction of sodium hydroxide into the solution to the end nitration equal to 150-400 g / l, and exposure at room temperature for 12-15 hours with the precipitation of non-ferrous metals in the precipitate, which is separated by filtration. 2. The method according to claim 1, in which alkali is added to the solution remaining after separation of the non-ferrous metal precipitate and the pH of the solution is adjusted to a value of at least 11, and iron trichloride is added in an amount exceeding the molar concentration of sodium hypophosphite contained in the solution by at least at least 2 times, to clean the solution from phosphorus.