CN113512652B - Method for extracting gallium metal from coal-series solid waste - Google Patents
Method for extracting gallium metal from coal-series solid waste Download PDFInfo
- Publication number
- CN113512652B CN113512652B CN202110732108.XA CN202110732108A CN113512652B CN 113512652 B CN113512652 B CN 113512652B CN 202110732108 A CN202110732108 A CN 202110732108A CN 113512652 B CN113512652 B CN 113512652B
- Authority
- CN
- China
- Prior art keywords
- gallium
- solution
- aluminum
- iron
- coal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B58/00—Obtaining gallium or indium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/006—Wet processes
- C22B7/007—Wet processes by acid leaching
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C1/00—Electrolytic production, recovery or refining of metals by electrolysis of solutions
- C25C1/22—Electrolytic production, recovery or refining of metals by electrolysis of solutions of metals not provided for in groups C25C1/02 - C25C1/20
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Electrochemistry (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention discloses a method for extracting gallium metal from coal-series solid waste, and belongs to the technical field of metallurgy. Firstly, crushing coal-based solid waste to be treated, then obtaining leachate by adopting a nitric acid pressure leaching method, adding metastannic acid into the leachate to perform coprecipitation adsorption of iron and gallium, and sequentially washing and acid-washing the obtained coprecipitation slag for regeneration; and (3) carrying out ionic membrane enrichment on the pickling solution, adding alkali into the enrichment solution to remove iron, then carrying out a carbonation method twice to generate aluminum-gallium mixed salt, and finally carrying out alkali dissolution electrolysis to obtain high-purity gallium. The invention realizes that the total recovery rate of gallium is higher than 70 percent and the purity of the produced gallium is up to more than 99.9 percent by the synergistic combination of various process steps such as acid dissolution, coprecipitation and enrichment, alkali dissolution iron removal, step carbonation, alkali dissolution electrolysis and the like and related process parameters, and simultaneously, the process has the advantages of low energy consumption, low equipment requirement, good impurity removal effect, recyclable solvent and the like.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a method for extracting gallium metal from coal-series solid waste.
Background
Gallium is a metal element which is extremely important for the development of high-tech industries, is widely applied to the fields of semiconductors, solar cells, alloys, medicine, glass manufacturing, chemical engineering and the like, and has good market prospect. Gallium is commonly associated with aluminum, zinc and the like in minerals in the natural world, and sulfide ore of zinc and bauxite ore are important raw materials for extracting gallium. Currently, 90% of the world's gallium is obtained from byproducts of the alumina industry, which uses bauxite as a major raw material.
The coal-based solid waste comprises fly ash and coal gangue and comes from the mining, processing and utilizing processes of coal. China is a large country for coal production and consumption, generates a large amount of coal-based solid waste every year, occupies a large amount of land resources, and seriously pollutes the environment. Therefore, the disposal and high-value comprehensive utilization of the coal-based solid waste have important research significance. However, the economic value of the main component alumina is mainly considered in the utilization method of the fly ash and coal gangue at present, and other components are often disposed as impurities. In fact, a large amount of precious rare metals such as gallium, germanium and the like also exist in the fly ash and the coal gangue. Therefore, the method has good economic benefit for effectively recovering the rare metals from the coal-based solid waste.
The extraction method of crops in the prior art mainly comprises a solvent extraction method, an extraction resin method and a lime milk carbonation method. Among them, the most effective extractant used in the solvent extraction method is Kelex l00, but the synthesis difficulty is high, the price is high, and the application is limited. The main procedures of the extraction resin method comprise adsorption, leaching, lean resin transformation and electrolysis, and the prior reports of industrial production have been carried out, however, the price of the chelating resin or the ion exchange resin adopted in the process is higher, and if the concentration of crops in the circulating mother liquor is lower, higher production cost is caused, and further popularization is influenced. The lime milk carbonating process includes introducing carbon dioxide into the alumina carbon mother liquor for complete carbonating decomposition, and adding lime milk for dealumination to enrich crop. In addition, the electrolysis method has become the main method for producing gallium at present due to the advantages of high product purity, low production cost and energy consumption, little three-waste pollution and the like, and the obtained gallium with the purity of more than 99.99 percent has good feasibility in the subsequent crystal pulling purification method.
Chinese patent application CN101255504A discloses a production process for extracting gallium from fly ash and coal gangue, which adopts a method of adsorption column adsorption to extract gallium from gallium-containing aluminum chloride solution, wherein the gallium-containing aluminum chloride solution is prepared by mixing and calcining fly ash and sodium carbonate, leaching with water, carbonizing,then reacting with hydrochloric acid. CN85100163A discloses a method for extracting crops from decomposition liquid in alumina production, which is to introduce CO into mother liquor after aluminum hydroxide is separated out by carbonation decomposition 2 Completely carbonating and decomposing to deposit the crystal and aluminum in the form of amorphous hydrate, separating the deposit and removing most of Na 2 Adding lime milk into the precipitate for dealumination to obtain a solution rich in crops, and introducing CO 2 Dissolving the precipitate with sodium hydroxide while adding sodium sulfide to eliminate heavy metal to obtain electrolyte solution containing 3.9g/L of crop; electrolyzing in an electrolytic bath with stainless steel as cathode and anode to obtain crop on the cathode, and treating with hydrochloric acid to obtain metal crop with purity of 99.99-99.999%. CN101284668A discloses a method for extracting silicon dioxide, aluminum oxide and gallium oxide from high-alumina fly ash, which is characterized in that residues obtained after silicon oxide is extracted from fly ash are treated to obtain gallium-containing sodium metaaluminate solution which is used as mother liquor for separating and enriching gallium, and then gallium is enriched by adopting a fractional carbonation-sodium hydroxide dissolution method and a resin adsorption method. CN101130835A discloses a production method for extracting gallium, which takes intermediate carbon content mother liquor obtained in the process of producing alumina by fly ash as a raw material, and obtains gallium concentrate after reaction and complete carbonation with sodium bicarbonate. In addition, zhao Yi reports "experimental research on gallium separation from fly ash" (north China electric power technology, 1998, no.1, 35-37), and the research shows that a gallium-containing sodium metaaluminate solution obtained by sintering fly ash and limestone and leaching with a sodium carbonate solution can be used as a mother solution for separating and enriching gallium, and gallium can be extracted by a stepwise carbonation-sodium hydroxide dissolution method.
The reports of the prior art all adopt carbon content or seed precipitation mother liquor obtained in the process of extracting alumina from coal-based solid wastes as raw materials to separate and enrich gallium, namely the mother liquor for extracting gallium is alkaline gallium-containing sodium metaaluminate solution, and the methods have the problems of complex process, high gallium loss and the like.
Disclosure of Invention
Aiming at the defects and shortcomings in the prior art, the invention provides a method for extracting metal gallium from coal-based solid waste, which comprises the working procedures of acid dissolution, coprecipitation adsorption and enrichment, alkali dissolution for removing iron, calcium and magnesium impurities, stepwise carbonation for removing aluminum, alkali dissolution for enriching gallium, electrolysis and the like, wherein the total recovery rate of the gallium is higher than 70 percent finally. The method has the advantages of low energy consumption, low equipment requirement, good impurity removal effect, recyclable solvent and the like.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method for extracting metal gallium from coal-based solid waste comprises the following steps:
(1) Crushing coal-based solid waste to be treated, and obtaining pickle liquor by adopting a nitric acid pressure leaching method;
(2) Adding metastannic acid into the pickle liquor for coprecipitation reaction, filtering after full reaction to obtain iron-removed liquor and coprecipitation slag containing iron and gallium, washing the coprecipitation slag with water to remove most of aluminum, calcium and magnesium, and then pickling with nitric acid to recover iron and gallium to obtain absorbing liquor containing iron and gallium;
(3) Carrying out nanofiltration membrane separation on the absorption liquid to obtain dilute nitric acid and enriched liquid containing iron and gallium, and returning the dilute nitric acid to the co-precipitation slag pickling process;
(4) Adding a sodium hydroxide solution into the enrichment solution, and removing iron and a small amount of residual calcium and magnesium elements in the solution to obtain a gallium-containing sodium metaaluminate solution;
(5) Introducing carbon dioxide into the gallium-containing sodium metaaluminate solution, controlling the pH value of the solution to precipitate aluminum and gallium in the solution step by step to obtain crude aluminum hydroxide and crude gallium hydroxide;
(6) And adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain the metal gallium.
Further, the coal-based solid waste is crushed to the particle size of 0.02-0.1mm in the step (1).
Further, in the nitric acid pressure leaching method in the step (1), the mass concentration of the nitric acid solution is 10-50%, the heat preservation temperature is above 150 ℃, the heat preservation time is 0.5-5h, and the stirring speed is 300-700r/min.
Further, the chemical element composition of the pickle liquor in the step (1) comprises: fe is 0.1-0.6g/L; the Al content is 45.6-78.9g/L; si is 0.01-0.15g/L; ca is 0.15-2.46g/L; mg is 0.01-0.6g/L; ga is 0.01-0.2g/L.
Further, the pH value of the coprecipitation reaction in the step (2) is 0.5-3.0, the temperature is 20-80 ℃, the consumption of the metastannic acid is 1-10% of the mass of the pickle liquor, and the heat preservation time is 0.5-3h. After iron and gallium are adsorbed by metastannic acid coprecipitation, the iron and gallium can be recycled by acid washing.
Further, in the step (2), the adsorption rate of iron in the metastannic acid coprecipitation reaction is 90-99%, and the adsorption rate of gallium is 70-80%; when the co-precipitation slag is washed by water, the washing-out rate of aluminum, calcium and magnesium is more than 90 percent, and the washing-out rate of iron and gallium is less than 5 percent; the elution rate of iron and gallium is more than 95 percent when the co-precipitation slag is subjected to acid washing.
Further, the liquid-solid ratio of the co-precipitation slag water washing in the step (2) is 3-10; the liquid-solid ratio of the co-precipitation slag pickling is 3-10, and the mass concentration of the used nitric acid is 20-60%.
Further, the mass percentage of gallium in the enrichment solution in the step (3) is 0.05-0.5%.
Further, in the step (4), a sodium hydroxide solution is added into the enriched solution, the pH value of the solution is controlled to be 13-14, and the mass concentration of the sodium hydroxide solution is 30%. Adding a sodium hydroxide solution into the enrichment solution under stirring, controlling the pH value of the solution to enable aluminum nitrate, gallium nitrate and sodium hydroxide in the enrichment solution to react to generate sodium metaaluminate and sodium metagallate, forming precipitates of iron, calcium, magnesium and the like in the solution in the form of hydroxides, filtering, separating and washing to obtain the gallium-containing sodium metaaluminate solution.
Further, the step (5) specifically includes:
primary carbon differentiation: directly introducing carbon dioxide gas into the gallium-containing sodium metaaluminate mother liquor for carbon differentiation, wherein the gas flow rate is 100-200ml/min, the uniformity of the reaction is ensured, the reaction temperature is controlled to be 60-80 ℃, the carbonation time is 1-5h, the pH at the end point of the reaction is 9.5-11.3, most of aluminum generates aluminum hydroxide precipitate after the reaction, gallium is left in the solution, and the mass ratio of gallium to aluminum in the filtrate after the aluminum hydroxide precipitate is separated is more than 1:90, respectively;
secondary carbon differentiation: and (3) continuously introducing carbon dioxide gas into the filtrate, controlling the gas flow rate to be 150-250ml/min, controlling the reaction temperature to be 60-80 ℃, the carbon decomposition time to be 2-5h, controlling the pH at the end of the reaction to be 8.5-8.9, precipitating all aluminum hydroxide and most gallium, filtering to obtain aluminum-gallium mixed salt precipitate, evaporating and crystallizing the obtained filtrate to separate sodium carbonate crystals, and returning the gallium-containing liquid after separating the sodium carbonate to the step (4), wherein the mass ratio of gallium to aluminum in the aluminum-gallium mixed salt is more than 1:50.
Further, the mass concentration of the sodium hydroxide solution in the step (6) is 15-30%.
Compared with the prior art, the technical scheme of the invention has the following technical advantages or positive effects:
(1) The method for extracting gallium disclosed by the invention is suitable for various gallium-containing coal-series solid wastes, and has wide raw material applicability;
(2) The invention adopts the nitric acid pressure leaching method to directly leach gallium from the raw materials, thereby ensuring that the leaching rate of gallium is up to more than 90 percent;
(3) The total recovery rate of gallium in the invention is higher than 70%, and the purity of gallium obtained by electrolysis is up to more than 99.9%;
(4) The process has the advantages of low energy consumption, low equipment requirement, good impurity removal effect, recyclable solvent and the like.
Drawings
Fig. 1 is a process flow diagram of the method for extracting gallium metal from coal-based solid waste according to the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below.
[ example 1 ] A method for producing a polycarbonate
Crushing the coal-series solid waste to be treated to the granularity of 0.02mm, leaching the raw material by adopting a nitric acid solution with the mass concentration of 10%, wherein the temperature of the leaching reaction is 160 ℃, the heat preservation time is 5h, and the stirring speed is 300r/min.
And (3) coprecipitating the obtained pickle liquor by metastannic acid to adsorb iron and gallium, keeping the temperature for 1h at the temperature of 20 ℃ and the content of metastannic acid of 2 percent, and filtering to obtain coprecipitation slag and iron-removed liquor.
The contents of iron, aluminum, calcium, magnesium and gallium in the solution before and after coprecipitation were measured, and the measurement results are shown in table 1.
TABLE 1 test results of the contents of substances before and after the coprecipitation of metastannic acid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Pickle liquor | 0.27 | 56.65 | 4.05 | 0.38 | 0.0062 |
| Liquid after iron removal | 0.012 | 54.36 | 3.81 | 0.34 | 0.0019 |
Washing the obtained coprecipitation slag with water, then washing with acid, eluting and regenerating, wherein the washing liquid solid ratio is 10:1, stirring and washing for 1 hour at normal temperature, and filtering to obtain washing slag and washing liquid; and (3) stirring and washing the washing slag at the liquid-solid ratio of 10 and the mass concentration of nitric acid of 30% for 1h at normal temperature, and filtering to obtain pickling slag and pickling solution.
The contents of iron, aluminum, calcium, magnesium and gallium in the water washing solution and the pickling solution were measured, and the measurement results are shown in table 2.
TABLE 2 test results of the content of substances in the co-precipitation sludge washing liquid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Water washing liquid | 0.047 | 7.81 | 0.92 | 0.56 | 0.001 |
| Pickling solution | 2.58 | 0.72 | 0.08 | 0.047 | 0.021 |
The pickling solution was subjected to membrane filtration using a nanofiltration membrane, and the composition of the solution after membrane filtration is shown in table 3.
TABLE 3 test results of the content of substances after the nanofiltration membrane treatment of the pickle water
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | Nitric acid (%) | |
| Fresh water | 0.0043 | 0.79 | 0.078 | 0.041 | 0.0002 | 15 |
| Concentrated solution | 26.5 | 8.2 | 0.94 | 0.46 | 0.48 | 4.1 |
At 65 ℃, carbon dioxide gas is introduced into 100ml of sodium metaaluminate mother liquor at the speed of 100ml/min, the pH value of the reaction end point is controlled to be 9.5, and the primary carbonation is finished by filtering. And (3) carrying out secondary carbonation on the solution after the aluminum hydroxide precipitate is separated by the primary carbonation, continuously introducing carbon dioxide gas at the temperature of 50 ℃ at the speed of 120ml/min, controlling the pH value at the end point of the reaction to be 8.5, and filtering to obtain the aluminum-gallium mixed salt precipitate. According to measurement, the mass ratio of gallium to aluminum in the aluminum-gallium mixed salt is 1:45.
and adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain the metal gallium. The overall recovery of gallium was calculated to be 75.6%.
[ example 2 ] A method for producing a polycarbonate
Crushing the coal-series solid waste to be treated to the granularity of 0.05mm, leaching the raw material by using a nitric acid solution with the mass concentration of 20%, wherein the temperature of the leaching reaction is 170 ℃, the heat preservation time is 1.5h, and the stirring speed is 400r/min.
And (3) coprecipitating the obtained pickle liquor by metastannic acid to adsorb iron and gallium, keeping the temperature for 1h at the temperature of 30 ℃ and the content of metastannic acid of 3 percent, and filtering to obtain coprecipitation slag and iron-removed liquor.
The contents of iron, aluminum, calcium, magnesium and gallium in the solution before and after coprecipitation were measured, and the measurement results are shown in table 1.
TABLE 1 test results of the contents of substances before and after the coprecipitation of metastannic acid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Pickle liquor | 0.25 | 58.65 | 4.07 | 0.35 | 0.0068 |
| Liquid after iron removal | 0.008 | 58.36 | 3.41 | 0.30 | 0.0014 |
Washing the obtained coprecipitation slag with water, then washing with acid, eluting and regenerating, wherein the washing liquid solid ratio is 7:1, stirring and washing for 1 hour at normal temperature, and filtering to obtain washing slag and washing liquid; and (3) stirring and washing the washing slag at the liquid-solid ratio of 7:1 and the mass concentration of nitric acid of 35% for 1h at normal temperature, and filtering to obtain pickling slag and pickling solution.
The contents of iron, aluminum, calcium, magnesium and gallium in the water washing solution and the pickling solution were measured, and the measurement results are shown in table 2.
TABLE 2 test results of the content of substances in the co-precipitation sludge washing liquid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Water washing liquid | 0.042 | 7.91 | 0.98 | 0.58 | 0.001 |
| Pickling solution | 2.65 | 0.82 | 0.085 | 0.049 | 0.021 |
The pickle liquor was subjected to membrane filtration, here with a nanofiltration membrane, the solution composition after membrane filtration being shown in table 3.
TABLE 3 test results of the content of substances after the nanofiltration membrane treatment of the pickle water
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | Nitric acid (%) | |
| Fresh water | 0.0046 | 0.78 | 0.088 | 0.048 | 0.0003 | 12 |
| Concentrated solution | 24.5 | 8.5 | 0.95 | 0.43 | 0.28 | 4 |
At 65 ℃, carbon dioxide gas is introduced into 100ml of sodium metaaluminate mother liquor at the speed of 100ml/min, the pH value of the reaction end point is controlled to be 9.5, and the primary carbonation is finished by filtering. And (3) carrying out secondary carbonation on the solution after the aluminum hydroxide precipitate is separated by the primary carbonation, continuously introducing carbon dioxide gas at the temperature of 50 ℃ at the speed of 120ml/min, controlling the pH value at the end point of the reaction to be 8.5, and filtering to obtain the aluminum-gallium mixed salt precipitate. According to measurement, the mass ratio of gallium to aluminum in the aluminum-gallium mixed salt is 1:50.
and adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain metal gallium. The overall recovery of gallium was calculated to be 76.6%.
[ example 3 ]
Crushing the coal-series solid waste to be treated to the granularity of 0.07mm, leaching the raw material by adopting a nitric acid solution with the mass concentration of 30%, wherein the temperature of the leaching reaction is 200 ℃, the heat preservation time is 2.0h, and the stirring speed is 450r/min.
And (3) coprecipitating the obtained pickle liquor by metastannic acid to adsorb iron and gallium, keeping the temperature for 1h at the temperature of 60 ℃ and the content of metastannic acid of 10 percent, and filtering to obtain a coprecipitation slag and a liquor after iron removal.
The contents of iron, aluminum, calcium, magnesium and gallium in the solution before and after coprecipitation were measured, and the measurement results are shown in table 1.
TABLE 1 test results of the contents of substances before and after the coprecipitation of metastannic acid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Pickle liquor | 0.25 | 58.65 | 4.07 | 0.35 | 0.0068 |
| Liquid after iron removal | 0.008 | 58.36 | 3.41 | 0.30 | 0.0014 |
Washing the obtained coprecipitation slag with water, then washing with acid, eluting and regenerating, wherein the washing liquid solid ratio is 5:1, stirring and washing for 1 hour at normal temperature, and filtering to obtain washing slag and washing liquid; and (3) stirring and washing the washing slag at the liquid-solid ratio of 5:1 and the mass concentration of nitric acid of 40% for 1h at normal temperature, and filtering to obtain pickling slag and pickling solution.
The contents of iron, aluminum, calcium, magnesium and gallium in the water washing solution and the pickling solution were measured, and the measurement results are shown in table 2.
TABLE 2 test results of the content of substances in the co-precipitation sludge washing liquid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Water washing liquid | 0.072 | 8.61 | 0.99 | 0.78 | 0.003 |
| Pickling solution | 2.65 | 0.82 | 0.095 | 0.049 | 0.041 |
The pickle liquor was subjected to membrane filtration, here with a nanofiltration membrane, the solution composition after membrane filtration being shown in table 3.
TABLE 3 test results of the content of substances after the nanofiltration membrane treatment of the pickle water
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | Nitric acid (%) | |
| Fresh water | 0.0066 | 0.95 | 0.098 | 0.068 | 0.0006 | 18 |
| Concentrated solution | 27.5 | 8.5 | 0.93 | 0.48 | 0.58 | 5 |
At 65 ℃, carbon dioxide gas is introduced into 100ml of sodium metaaluminate mother liquor at the speed of 100ml/min, the pH value of the reaction end point is controlled to be 9.5, and the primary carbonation is finished by filtering. And (3) carrying out secondary carbonation on the solution after the aluminum hydroxide precipitate is separated by the primary carbonation, continuously introducing carbon dioxide gas at the temperature of 60 ℃ at the speed of 120ml/min, controlling the pH value at the end point of the reaction to be 8.5, and filtering to obtain the aluminum-gallium mixed salt precipitate. The weight ratio of gallium to aluminum in the aluminum-gallium mixed salt at this time was determined to be 1:53.
and adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain the metal gallium. The overall recovery of gallium was calculated to be 77.6%.
[ example 4 ]
Crushing the coal-based solid waste to be treated to the granularity of 0.1mm, leaching the raw material by adopting a nitric acid solution with the mass concentration of 50%, wherein the temperature of the leaching reaction is 210 ℃, the heat preservation time is 0.5h, and the stirring speed is 700r/min.
And (3) coprecipitating the obtained pickle liquor by metastannic acid to adsorb iron and gallium, keeping the temperature for 1h at 80 ℃ with the pH =1 and the content of metastannic acid of 10 percent, and filtering to obtain coprecipitation slag and iron-removed liquor.
The contents of iron, aluminum, calcium, magnesium and gallium in the solution before and after coprecipitation were measured, and the measurement results are shown in table 1.
TABLE 1 test results of the contents of the materials before and after coprecipitation of metastannic acid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Pickle liquor | 0.45 | 63.65 | 4.97 | 0.66 | 0.0083 |
| Liquid after iron removal | 0.014 | 62.67 | 3.83 | 0.56 | 0.0018 |
Washing the obtained coprecipitation slag with water, then washing with acid, eluting and regenerating, wherein the washing liquid solid ratio is 5:1, stirring and washing for 1 hour at normal temperature, and filtering to obtain washing slag and washing liquid; and (3) stirring and washing the washing slag at the liquid-solid ratio of 5:1 and the mass concentration of nitric acid of 60% for 1h at normal temperature, and filtering to obtain pickling slag and pickling solution.
The contents of iron, aluminum, calcium, magnesium and gallium in the water washing solution and the pickling solution were measured, and the measurement results are shown in table 2.
TABLE 2 test results of the content of substances in the co-precipitation sludge washing liquid
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | |
| Water washing liquid | 0.072 | 8.61 | 0.99 | 0.78 | 0.003 |
| Pickling solution | 2.65 | 0.82 | 0.095 | 0.049 | 0.041 |
The pickle liquor was subjected to membrane filtration, here with a nanofiltration membrane, the solution composition after membrane filtration being shown in table 3.
TABLE 3 test results of the content of substances after the nanofiltration membrane treatment of the pickle water
| Iron (g/L) | Aluminum (g/L) | Magnesium (g/L) | Calcium (g/L) | Gallium (g/L) | Nitric acid (%) | |
| Fresh water | 0.0066 | 0.95 | 0.098 | 0.068 | 0.0006 | 28 |
| Concentrated solution | 27.5 | 8.5 | 0.93 | 0.48 | 0.58 | 4.2 |
At 65 ℃, carbon dioxide gas is introduced into 100ml of sodium metaaluminate mother liquor at the speed of 100ml/min, the pH value of the reaction end point is controlled to be 9.5, and the primary carbonation is finished by filtering. And (3) carrying out secondary carbonation on the solution after the aluminum hydroxide precipitate is separated by the primary carbonation, continuously introducing carbon dioxide gas at the temperature of 50 ℃ at the speed of 120ml/min, controlling the pH value at the end point of the reaction to be 8.5, and filtering to obtain the aluminum-gallium mixed salt precipitate. The weight ratio of gallium to aluminum in the aluminum-gallium mixed salt at this time was determined to be 1:56.
and adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain the metal gallium. The overall recovery of gallium was calculated to be 77.9%.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the scope of the present invention, which is intended to cover any modifications, equivalents, improvements, etc. within the spirit and scope of the present invention.
Claims (5)
1. A method for extracting gallium metal from coal-based solid waste is characterized by comprising the following steps:
(1) Crushing the coal-series solid waste to be treated to the granularity of 0.07-0.1mm, and obtaining pickle liquor by adopting a nitric acid pressure leaching method; in the nitric acid pressure leaching method, the mass concentration of a nitric acid solution is 30-50%, the heat preservation temperature is 200-210 ℃, the heat preservation time is 0.5-2h, and the stirring speed is 450-700r/min;
(2) Adding metastannic acid into the pickle liquor for coprecipitation reaction, filtering after full reaction to obtain iron-removed liquor and coprecipitation slag containing iron and gallium, washing the coprecipitation slag with water to remove most of aluminum, calcium and magnesium, and then pickling with nitric acid to recover iron and gallium to obtain absorbing liquor containing iron and gallium; in the step (2), the pH value of the coprecipitation reaction is 1-3.0, the temperature is 60-80 ℃, the consumption of metastannic acid is 3-10% of the mass of the pickle liquor, and the heat preservation time is 0.5-3h; in the step (2), the liquid-solid ratio of the co-precipitation slag washing is 5-10; the liquid-solid ratio of the coprecipitation slag pickling is 5-7:1, and the mass concentration of the used nitric acid is 40-60%;
(3) Carrying out nanofiltration membrane separation on the absorption liquid to obtain dilute nitric acid and enriched liquid containing iron and gallium, and returning the dilute nitric acid to the co-precipitation slag pickling process; the mass percentage content of gallium in the enrichment solution is 0.05-0.5%;
(4) Adding a sodium hydroxide solution into the enrichment solution, and removing iron and a small amount of residual calcium and magnesium elements in the solution to obtain a gallium-containing sodium metaaluminate solution;
(5) Introducing carbon dioxide into the gallium-containing sodium metaaluminate solution, and controlling the pH value of the solution to precipitate aluminum and gallium in the solution step by step to obtain crude aluminum hydroxide and crude gallium hydroxide;
the step (5) of controlling the pH value of the solution to precipitate aluminum and gallium in the solution step by step specifically comprises the following steps:
primary carbon differentiation: directly introducing carbon dioxide gas into the gallium-containing sodium metaaluminate mother liquor for carbon differentiation, wherein the gas flow rate is 100-200ml/min, the uniformity of the reaction is ensured, the reaction temperature is controlled to be 60-80 ℃, the carbonation time is 1-5h, the pH value at the end point of the reaction is 9.5-11.3, most of aluminum generates aluminum hydroxide precipitate after the reaction, gallium is remained in the solution, and the mass ratio of gallium to aluminum in the filtrate after the aluminum hydroxide precipitate is separated is more than 1:90, respectively;
secondary carbon differentiation: continuously introducing carbon dioxide gas into the filtrate, controlling the gas flow rate to be 150-250ml/min, controlling the reaction temperature to be 60-80 ℃, carrying out carbon decomposition for 2-5h, controlling the pH at the end of the reaction to be 8.5-8.9, precipitating all aluminum hydroxide and most gallium, filtering to obtain aluminum-gallium mixed salt precipitate, evaporating and crystallizing the obtained filtrate to separate sodium carbonate crystals, returning the gallium-containing liquid after separating the sodium carbonate to the step (4), wherein the mass ratio of gallium to aluminum in the aluminum-gallium mixed salt is more than 1: 50;
(6) And adding the crude gallium hydroxide into a sodium hydroxide solution to obtain a gallium-containing alkali solution, and electrolyzing the gallium-containing alkali solution to obtain the metal gallium.
2. The method for extracting gallium metal from coal-based solid waste according to claim 1, wherein the chemical element composition of the pickle liquor in step (1) comprises: fe is 0.1-0.6g/L; al is 45.6-78.9g/L; si is 0.01-0.15g/L; ca is 0.15-2.46g/L; mg is 0.01-0.6g/L; ga is 0.01-0.2g/L.
3. The method for extracting gallium metal from coal-based solid waste as claimed in claim 1, wherein in step (2), the iron adsorption rate is 90-99% and the gallium adsorption rate is 70-80% in the coprecipitation reaction of metastannic acid; when the co-precipitation slag is washed by water, the washing-out rate of aluminum, calcium and magnesium is more than 90 percent, and the washing-out rate of iron and gallium is less than 5 percent; the elution rate of iron and gallium is more than 95 percent when the co-precipitation slag is subjected to acid washing.
4. The method for extracting gallium metal from coal-based solid waste according to claim 1, wherein in the step (4), a sodium hydroxide solution is added into the enriched liquid, the pH of the solution is controlled to be 13-14, and the mass concentration of the sodium hydroxide solution is 30%.
5. The method for extracting gallium metal from coal-based solid waste according to claim 1, wherein the mass concentration of the sodium hydroxide solution in the step (6) is 15-30%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110732108.XA CN113512652B (en) | 2021-06-29 | 2021-06-29 | Method for extracting gallium metal from coal-series solid waste |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110732108.XA CN113512652B (en) | 2021-06-29 | 2021-06-29 | Method for extracting gallium metal from coal-series solid waste |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113512652A CN113512652A (en) | 2021-10-19 |
| CN113512652B true CN113512652B (en) | 2022-11-25 |
Family
ID=78066475
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110732108.XA Active CN113512652B (en) | 2021-06-29 | 2021-06-29 | Method for extracting gallium metal from coal-series solid waste |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113512652B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115612863B (en) * | 2022-08-30 | 2024-01-16 | 中南大学 | Method for separating gallium from alkaline solution |
| CN115786714B (en) * | 2022-12-21 | 2023-07-18 | 贵州大学 | Method for extracting gallium and rubidium from brown fused alumina dust and combining gallium and rubidium into compound fertilizer |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1693492A (en) * | 2005-05-13 | 2005-11-09 | 中南大学 | Method for recovering gallium and arsenic from gallium arsenide industrial waste |
| CN101368231A (en) * | 2008-09-25 | 2009-02-18 | 吉林大学 | Method for extracting metal gallium from fly ash |
| CN101864525A (en) * | 2010-04-27 | 2010-10-20 | 中国神华能源股份有限公司 | Method for extracting gallium from fly ash |
| CN102515220B (en) * | 2011-11-25 | 2013-09-18 | 潘安标 | Method for extracting alumina and gallium oxide from pulverized fuel ash to prepare aluminum oxide nanometer and polymeric ferric silicate sulfate |
| WO2013177583A2 (en) * | 2012-05-25 | 2013-11-28 | Neumann Systems Group, Inc. | System and method for selectively removing metals from industrial waste |
| CN103060573B (en) * | 2012-12-06 | 2014-07-09 | 中南大学 | Comprehensive recovery technology of valuable components in corundum smelting smoke ash containing gallium and potassium |
| CN112939046A (en) * | 2021-02-26 | 2021-06-11 | 四川顺应动力电池材料有限公司 | Comprehensive recycling method of coal-based solid waste |
| CN112981092B (en) * | 2021-04-23 | 2021-07-23 | 中国煤炭地质总局勘查研究总院 | Pretreatment activation method of fly ash and method for extracting gallium, lithium and rare earth metals therefrom |
-
2021
- 2021-06-29 CN CN202110732108.XA patent/CN113512652B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113512652A (en) | 2021-10-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102206755B (en) | Method for separating and recovering valuable elements from neodymium-iron-boron wastes | |
| CN110885090A (en) | Method for preparing battery-grade lithium carbonate by using lepidolite as raw material through one-step method | |
| CN106611841B (en) | A method for preparing nickel-cobalt-manganese ternary material precursor by utilizing nickel-cobalt slag material | |
| CN114105171A (en) | Method for recycling and comprehensively utilizing lepidolite and lithium hydroxide prepared by method | |
| CN110760680B (en) | Method for leaching, recovering and separating cobalt from manganese-sulfur purification waste residue | |
| CN111575491B (en) | Resource comprehensive utilization method for purifying cobalt-nickel slag by zinc hydrometallurgy arsenic salt | |
| CN101956070A (en) | Recovery method of molybdenum concentrates | |
| CN113512652B (en) | Method for extracting gallium metal from coal-series solid waste | |
| CN112522512B (en) | Method for preparing battery-grade cobalt sulfate by using organic cobalt slag of zinc smelting plant | |
| CN111636001A (en) | Acid-base combined method for treating bastnaesite and recovering rare earth from waste slag | |
| CN102094127B (en) | A method for recovering nickel and magnesium elements from high-magnesium type low-grade nickel sulfide ore | |
| CN113955775B (en) | Method for extracting lithium carbonate from lithium-rich clay by acid-base combined method | |
| Liu et al. | A new process of extracting vanadium from stone coal | |
| CN105039724A (en) | Smelting furnace soot treatment method | |
| CN111762804B (en) | Iron removal method for pickle liquor in acid process aluminum extraction | |
| KR102788067B1 (en) | Selective recovery method of valuable metals using solvent extraction from lithium secondary battery waste | |
| CN111778404A (en) | Leaching separation method of nickel-cobalt-molybdenum-phosphorus-vanadium alloy material | |
| CN108441649B (en) | Method for extracting nickel from chemical precipitation nickel sulfide material | |
| CN109777972B (en) | Method for extracting scandium from coal gangue through concentrated sulfuric acid activated leaching | |
| CN110643811B (en) | A kind of nickel-molybdenum ore full wet cleaning smelting process | |
| CN117758080A (en) | Method for extracting scandium by combining titanium white waste acid and alkali precipitation waste residue | |
| CN113735179B (en) | Method for preparing high-purity ferric sulfate by utilizing ferro-manganese | |
| CN116179874A (en) | Method for separating and extracting lithium in carbonate clay type lithium ore | |
| CN115505742A (en) | Samarium cobalt recovery method for samarium cobalt magnetic material | |
| CN114262797A (en) | A kind of method for effectively separating and recovering iron and aluminum from red mud sodium roasting slag |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20211126 Address after: 620000 Jinxiang Chemical Industrial Park, Meishan City, Sichuan Province Applicant after: Meishan compliance Recycling Resources Co.,Ltd. Address before: 620010 No. 1 Jinhua Road, Meishan high tech Industrial Park, Dongpo District, Meishan City, Sichuan Province Applicant before: Sichuan compliance power battery materials Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |