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GB2184108A - Gallium production - Google Patents

Gallium production Download PDF

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Publication number
GB2184108A
GB2184108A GB8629961A GB8629961A GB2184108A GB 2184108 A GB2184108 A GB 2184108A GB 8629961 A GB8629961 A GB 8629961A GB 8629961 A GB8629961 A GB 8629961A GB 2184108 A GB2184108 A GB 2184108A
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GB
United Kingdom
Prior art keywords
gallium
dust
organic phase
solution
aqueous
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.)
Granted
Application number
GB8629961A
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GB8629961D0 (en
GB2184108B (en
Inventor
Gunner Haagen Boe
Svein Erik Engdal
Roald Gundersen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Elkem ASA
Original Assignee
Elkem ASA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Elkem ASA filed Critical Elkem ASA
Publication of GB8629961D0 publication Critical patent/GB8629961D0/en
Publication of GB2184108A publication Critical patent/GB2184108A/en
Application granted granted Critical
Publication of GB2184108B publication Critical patent/GB2184108B/en
Expired legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B58/00Obtaining gallium or indium
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G15/00Compounds of gallium, indium or thallium
    • C01G15/003Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/26Treatment or purification of solutions, e.g. obtained by leaching by liquid-liquid extraction using organic compounds
    • C22B3/38Treatment or purification of solutions, e.g. obtained by leaching by liquid-liquid extraction using organic compounds containing phosphorus
    • C22B3/384Pentavalent phosphorus oxyacids, esters thereof
    • C22B3/3846Phosphoric acid, e.g. (O)P(OH)3
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B7/00Working 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
    • C22B7/02Working-up flue dust
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

A method of producing gallium from gallium-containing dust (e.g. dust which is recovered from gas collecting systems in plants for the electrolytic production of aluminium) comprises leaching the dust in an aqueous hydrochloric acid solution (e.g. at a temperature between 50 DEG and 120 DEG C) whereby gallium is leached as gallium chloride. Gallium chloride is thereafter selectively extracted from the leach solution by an organic phase consisting of substantially undiluted tri-n-butyl-phosphate, whereafter gallium is stripped from the organic phase by water or an alkaline solution e.g. of NaOH with a concentration of 0.1 to 3 M, preferably 1-2 M.

Description

SPECIFICATION Gallium production The present invention relates to a method for producing gallium, e.g. from a dust recovered in gas collecting systems in plants for electrolytic production of aluminium from a mixture of bauxite and cryolite.
The main constituents of this dust are carbon and oxides of aluminium, sodium and iron. The dust normally contains about 0.2 to about 0.5 % by weight of gallium.
It is known to recover gallium from the above-identified dust by mixing the dust with an excess of a carbonate of an alkali metal or a hydroxide of an alkali metal, treating this mixture at elevated temperature in an oxidizing atmosphere, whereafter the treated product is leached in an aqueous solution to dissolve gallium. Thereafter gallium is extracted from the leach solution for example by liquid-liquid extraction. The gallium recover is, however, low and normally below 70%.
It is further known that clay (aluminium silicate) containing small amounts of gallium can be treated with hydrochloric acid in order to leach the gallium and that gallium can be extracted from the pregnant leach solution by liquid-liquid extraction using an amine-compound as extractant. Gallium is then stripped from the organic phase by a strip solution containing hydrochloric acid, whereby a GACI3 solution is obtained. The aluminium silicate material is, however, very different from dust recovered in gas collecting systems in plants for electrolytic production of aluminium.
Finally, it is known that gallium can be extracted from discarded solutions from germanium production by using diluted tri-n-butyl-phosphate (TBP) as an organic extractant. These kind of solutions are mixtures of sulphuric acid and hydrochloric acid and it is necessary to use an organic extractant comprising 10% TBP dissolved in an aliphatic thinner in order to obtain selective extraction of gallium. This implies that great amounts of organic solution have to be used.
It is an object of the present invention to provide a simple and low cost method for producing gallium wherein high purity gallium can be recovered from dust such as may be recovered from gas collecting systems in plants for electrolytic production of aluminium.
According to the present invention, there is provided a method of extracting gallium from gallium-containing dust, in which the dust is treated with an aqueous hydrochloric acid solution whereby the gallium is dissolved as gallium chloride to form an aqueous leach solution, whereafter gallium chloride is extracted from the aqueous leach solution by an organic phase consisting of substantially undiluted tri-n-butyl-phosphate and the gallium is stripped from the organic phase by water or an aqueous alkaline solution.
The aqueous alkali solution preferably contains an alkali metal hydroxide such as sodium hydroxide. The concentration of hydroxide ions (and therefore in the preferred case the concentration of sodium hydroxide) may range from 0.1 to 3 M and preferably from 1 to 2 M.
Accordingly, the present invention encompasses a method for selective extraction of gallium from dust collected in gas collecting systems in plants for electrolytic production of aluminium, wherein the dust is leached by an aqueous solution containing hydrochloric acid of a temperature of 50-120 C whereby gallium is leached as gallium chloride, whereafter gallium chloride is selectively extracted from the pregnant leach solution by means of an organic phase consisting of undiluted tri-n-butyl-phosphate and that gallium is stripped from the organic phase by means of water or a solution of NaOH wherein the concentration of NaOH is from 0.1 to 3 M, preferably 1 to 2 M.
The dust is preferably leached by a hydrochloric acid solution with an acidity of 3 to 8 M and at a temperature of 95 to 105do. According to a preferred embodiment of the present invention any ferric iron which is dissolved together with gallium, is reduced to ferrous iron by addition of a reducing agent, preferably iron powder, before the pregnant leach solution is contacted by the organic extraction phase.
According to another embodiment of the present invention, the dust is treated in an oxidizing atmosphere at a temperature of 500-1000"C before the leaching step. By this treatment carbon, fluorides and tar are removed from the dust, whereby the weight of the dust is reduced by about 50%.
By the method according to the present invention a high leaching yield of gallium of above 80% is achieved and gallium is selectively extracted by means of substantially undiluted TBP.
Use of undiluted TBP gives a substantial reduction of the volume of the organic extraction phase compared to the known method wherein an organic phase comprising 10% TBP diluted in an aliphatic thinner is used.
The present invention will now be further described in connection with the following examples.
Example I 200 g dust collected from a gas collecting system in a plant for electrolytic production of aluminium was leached by 1000 ml 6M hydrochloric acid solution. The leaching temperature was 100"C.
The chemical analysis of the dust was as follows: Carbon 33 % by weight Fluorine 17 % by weight Oxygen 17 % by weight Aluminium 13 % by weight Sodium 9 % by weight Iron 6 % by weight Sulphur 3 % by weight Calcium 1.6 % .by weight Gallium 0.47 % by weight The chemical analysis of the pregnant leach solution was as follows: Gallium 0.8 g/l Iron 13.4 g/l Aluminium 25.0 g/l Sodium 17.4 g/l Fluorine 29.4 g/l Chlorine 212 g/l The leaching yield for gallium was thus 85%.
Iron powder was added to the pregnant leach solution in order to reduce ferric iron to ferrous iron. The content of iron in the leach solution was thereby increased to 18.4 g/l.
Thereafter the pregnant leach solution was contacted by undiluted tri-n-butyl-phosphate at a volume ratio of aqueous phase to organic phase of 5/1 whereby gallium was extracted to the organic phase. The content of gallium in the leach solution was thereby reduced from 0.8 g/l to less than 0.02 g/l. This means that more than 97.5 % of gallium in the leach solution was extracted by contact with the undiluted TBP.
Gallium was then stripped from the organic phase by contacting the organic phase by water with pH 7 in two steps. The volume ratio water/organic was 1:1. The resultant aqueous solution containing gallium was thereafter again contacted by TBP with a volume ratio water/organic of 5/1. Gallium was thereafter stripped by contacting the organic phase with water in the same way as described above.
The final strip solution has the following analysis: Gallium 5 g/l Iron < 0.05 g/l Aluminium < 0.05 g/l Sodium 0.054 g/l Fluorine 0.026 g/l While the ratio of Ga/Fe in the pregnant leach solution was 0.06, the ratio of Ga/Fe in the final strip solution was greater than 100.
Example 2 In a pilot plant for continuous production of gallium from dust recovered from a gas collecting system in plants for electrolytic production of aluminium, 12 kg of dust was leached per hour in 30 lit/hour of 6M HCI. The leaching temperature was kept at 100"C.
The pregnant leach solution has the following average analysis: Gallium 1.1 girl Aluminium 35 g/l Iron 20 g/l Sodium 25 g/l Fluorine 50 g/l Chlorine 212 g/I Ferric iron in the pregnant leach solution was reduced to ferrous iron by addition of elemental iron. The average iron content in the leach solution thereby increased to 40 g/l.
The pregnant leach solution was thereafter contacted by undiluted tri-n-butyl-phosphate in a mixer/settling apparatus. The volume ratio of leach solution to TBP was regulated to 5/1.
Gallium was thereby extracted to the organic phase. The content of gallium in the leach solution was thereby reduced to below 0.02 g/l. This means that more than 98.1 % of the gallium content was extracted into the organic phase. 1/4 of the organic phase was continuously bleeded out for stripping of the gallium content.
The organic phase was returned to the extraction step after stripping.
Gallium was stripped from the organic phase by contacting the organic phase with water in a volume ratio organic phase/water of 1:1.
After having operated the pilot plant until equilibrium was reached the average content of the strip solution was: Gallium 15 g/l Iron 0.05 g/l Aluminium 0.003 g/l Fluorine 0.25 g/l Chlorine 40 g/l While the ratio of Ga/Fe in the pregnant leach solution was 0.06 the same ratio in the strip solution was 300. This shows that by the method of the present invention a very selective extraction of gallium is obtained.

Claims (14)

1. A method of extracting gallium from gallium-containing dust, in which the dust is treated with an aqueous hydrochloric acid solution whereby the gallium is dissolved as gallium chloride to form an aqueous leach solution, whereafter gallium chloride is extracted from the aqueous leach solution by an organic phase consisting of substantially undiluted tri-n-butyl-phosphate and the gallium is stripped from the organic phase by water or an aqueous alkaline solution.
2. A method according to claim 1, wherein the aqueous alkaline solution contains an alkali metal hydroxide.
3. A method according to claim 2, wherein the alkali metal is sodium.
4. A method according to claim 1, 2 or 3, wherein the concentration of hydroxide ions is from 0.1 to 3 M.
5. A method according to claim 1, 2 or 3, wherein the concentration of hydroxide ions is from 1 to 2 M.
6. A method according to any one of claims 1 to 5, wherein the dust is treated with an aqueous hydrochloric acid solution with an acidity of 3-8 M.
7rf A method according to any one of claims 1 to 6, wherein temperature of the treatment with aqueous hydrochloric acid is kept between 50 and 120"C.
8. A method according to any one of claims 1 to 6, wherein the temperature of the treatment with aqueous hydrochloric acid is kept between 95 and 105"C.
9. A method according to any one of claims 1 to 8, wherein ferric iron in the aqueous leach solution is reduced to ferrous iron by addition of a reducing agent before the pregnant leach solution is contacted by the organic phase.
10. A method according to any one of claims 1 to 9, wherein the dust is treated in an oxidizing atmosphere at a temperature between 500 and 1000"C before the leaching step.
11. A method for selective extraction of gallium from dust recovered from gas collecting systems in plants for electrolytic production of aluminium, wherein the dust is leached in an aqueous hydrochloric acid solution whereby gallium is dissolved as gallium chloride, whereafter gallium chloride is selectively extracted from the pregnant leach solution by an organic phase consisting of undiluted tri-n-butyl-phosphate and that gallium is stripped from the organic phase by water or an alkaline solution of NaOH with a concentration of NaOH between 0.1 and 3 M.
12. A method according to claim 11, wherein the NaOH concentration is between 0.1 and 3 M.
13. A method of extracting gallium substantially as herein described with reference to any one of the examples.
14. Gallium whene.ver extracted by a method according to any one of claims 1 to 13.
GB8629961A 1985-12-16 1986-12-16 Gallium production Expired GB2184108B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NO854797A NO158028C (en) 1985-12-16 1985-12-16 GALLIUM EXTRACTION.

Publications (3)

Publication Number Publication Date
GB8629961D0 GB8629961D0 (en) 1987-01-28
GB2184108A true GB2184108A (en) 1987-06-17
GB2184108B GB2184108B (en) 1989-10-18

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ID=19888611

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GB8629961A Expired GB2184108B (en) 1985-12-16 1986-12-16 Gallium production

Country Status (11)

Country Link
JP (1) JPS62156238A (en)
AU (1) AU572412B2 (en)
BR (1) BR8606230A (en)
CA (1) CA1309869C (en)
DE (1) DE3640381A1 (en)
ES (1) ES2002227A6 (en)
FR (1) FR2591582B1 (en)
GB (1) GB2184108B (en)
NL (1) NL8602997A (en)
NO (1) NO158028C (en)
NZ (1) NZ218419A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0318383A1 (en) * 1987-11-24 1989-05-31 Metaleurop S.A. Hydrometallurgical treatment of gallium-containing solutions
RU2232199C2 (en) * 2001-11-13 2004-07-10 Общество с ограниченной ответственностью "ВИКОР" Method for extracting of gallium from sludge in aluminum production
RU2237740C1 (en) * 2003-02-07 2004-10-10 Открытое акционерное общество "Всероссийский алюминиево-магниевый институт" Method of recovering gallium from solid gallium-containing materials
RU2319757C2 (en) * 2005-10-28 2008-03-20 Открытое акционерное общество "РУСАЛ ВСЕРОССИЙСКИЙ АЛЮМИНИЕВО-МАГНИЕВЫЙ ИНСТИТУТ "(ОАО "РУСАЛ ВАМИ") Gallium extraction method from waste products of process for electrolytic refining of aluminum
CN100396804C (en) * 2005-12-09 2008-06-25 韶关市华韦实业有限公司 Technology for extracting Gallium metal from lead-zine tail ore slug smelting by extracting-electrolytic method
RU2340402C1 (en) * 2007-04-02 2008-12-10 Государственное образовательное учреждение высшего профессионального образования Читинский государственный университет (ЧитГУ) Production line for extraction of rare and rare-earth elements from fly ash of thermal power plants

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103276407B (en) * 2013-05-13 2016-12-28 攀枝花学院 A kind of from low-grade containing gallium, ferrum raw material reclaim gallium and the method for ferrum
CN113667839B (en) * 2021-08-20 2022-06-28 安徽工业大学 Method for recovering metal gallium from gallium nitride waste under normal pressure
CN115418478B (en) * 2022-09-05 2023-08-01 山西大学 A method for synergistically extracting aluminum-iron-lithium-gallium from high-alumina solid waste acidic system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB991613A (en) * 1960-11-28 1965-05-12 Asahi Chemical Ind Process for the recovery of gallium
EP0021990A1 (en) * 1979-07-03 1981-01-07 Rhone-Poulenc Specialites Chimiques Process for treating mixtures of rare earth oxides and gallium oxides

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2848398A (en) * 1955-05-11 1958-08-19 Zh Sekitan Sogo Kenkyujo Recovery of gallium compounds from the combustion gases of coal
GB991614A (en) * 1960-08-27 1965-05-12 Asahi Chemical Ind Process for recovering gallium in the purification of crude alumina
DD127573A1 (en) * 1976-09-06 1977-10-05
FR2397464A2 (en) * 1977-07-13 1979-02-09 Rhone Poulenc Ind PROCESS FOR RECOVERING GALLIUM FROM VERY BASIC SOLUTIONS BY LIQUID / LIQUID EXTRACTION
FR2411894A1 (en) * 1977-12-15 1979-07-13 Rhone Poulenc Ind GALLIUM EXTRACTION PROCESS
FI70693C (en) * 1980-12-05 1986-10-06 Rhone Poulenc Ind FOERFARANDE FOER RENING AV EN GALLIUMLOESNING
JPS6058170B2 (en) * 1982-12-17 1985-12-18 三井アルミニウム工業株式会社 Method for recovering gallium from dust generated in an aluminum electrolytic furnace
JPS60166224A (en) * 1984-02-03 1985-08-29 Mitsui Alum Kogyo Kk Method of recovery of gallium from dust of aluminum smelting

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB991613A (en) * 1960-11-28 1965-05-12 Asahi Chemical Ind Process for the recovery of gallium
EP0021990A1 (en) * 1979-07-03 1981-01-07 Rhone-Poulenc Specialites Chimiques Process for treating mixtures of rare earth oxides and gallium oxides

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0318383A1 (en) * 1987-11-24 1989-05-31 Metaleurop S.A. Hydrometallurgical treatment of gallium-containing solutions
WO1989004878A1 (en) * 1987-11-24 1989-06-01 Metaleurop S.A. Process for hydrometallurgical treatment of a solution of galliferous substances
FR2624524A1 (en) * 1987-11-24 1989-06-16 Metaleurop Sa PROCESS FOR HYDROMETALLURGIC TREATMENT OF SOLUTION OF GALLIFEROUS MATERIALS
US5122241A (en) * 1987-11-24 1992-06-16 Metaleurop S.A. Process for the hydrometallurgical treatment of a solution of materials containing gallium
RU2232199C2 (en) * 2001-11-13 2004-07-10 Общество с ограниченной ответственностью "ВИКОР" Method for extracting of gallium from sludge in aluminum production
RU2237740C1 (en) * 2003-02-07 2004-10-10 Открытое акционерное общество "Всероссийский алюминиево-магниевый институт" Method of recovering gallium from solid gallium-containing materials
RU2319757C2 (en) * 2005-10-28 2008-03-20 Открытое акционерное общество "РУСАЛ ВСЕРОССИЙСКИЙ АЛЮМИНИЕВО-МАГНИЕВЫЙ ИНСТИТУТ "(ОАО "РУСАЛ ВАМИ") Gallium extraction method from waste products of process for electrolytic refining of aluminum
CN100396804C (en) * 2005-12-09 2008-06-25 韶关市华韦实业有限公司 Technology for extracting Gallium metal from lead-zine tail ore slug smelting by extracting-electrolytic method
RU2340402C1 (en) * 2007-04-02 2008-12-10 Государственное образовательное учреждение высшего профессионального образования Читинский государственный университет (ЧитГУ) Production line for extraction of rare and rare-earth elements from fly ash of thermal power plants

Also Published As

Publication number Publication date
FR2591582B1 (en) 1988-07-01
NZ218419A (en) 1989-04-26
GB8629961D0 (en) 1987-01-28
GB2184108B (en) 1989-10-18
CA1309869C (en) 1992-11-10
ES2002227A6 (en) 1988-07-16
NL8602997A (en) 1987-07-16
NO854797L (en) 1987-06-01
NO158028B (en) 1988-03-21
BR8606230A (en) 1987-09-29
FR2591582A1 (en) 1987-06-19
JPS642654B2 (en) 1989-01-18
AU6658886A (en) 1987-06-25
DE3640381A1 (en) 1987-06-04
AU572412B2 (en) 1988-05-05
NO158028C (en) 1988-06-29
JPS62156238A (en) 1987-07-11

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Effective date: 19931216