WO2000061826A1 - Purification of zinc-bearing material solutions containing manganese - Google Patents

Purification of zinc-bearing material solutions containing manganese Download PDF

Info

Publication number
WO2000061826A1
WO2000061826A1 PCT/CA2000/000352 CA0000352W WO0061826A1 WO 2000061826 A1 WO2000061826 A1 WO 2000061826A1 CA 0000352 W CA0000352 W CA 0000352W WO 0061826 A1 WO0061826 A1 WO 0061826A1
Authority
WO
WIPO (PCT)
Prior art keywords
zinc
manganese
concentration
constituent
bearing material
Prior art date
Application number
PCT/CA2000/000352
Other languages
French (fr)
Inventor
Cesar J. Ferron
Original Assignee
Lakefield Research Limited
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 Lakefield Research Limited filed Critical Lakefield Research Limited
Priority to AU35479/00A priority Critical patent/AU3547900A/en
Publication of WO2000061826A1 publication Critical patent/WO2000061826A1/en
Priority to US09/977,917 priority patent/US20020083795A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G45/00—Compounds of manganese
    • C01G45/10—Sulfates
    • 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
    • C22B19/00—Obtaining zinc or zinc oxide
    • C22B19/20—Obtaining zinc otherwise than by distilling
    • C22B19/26—Refining solutions containing zinc values, e.g. obtained by leaching zinc ores
    • 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
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/44—Treatment or purification of solutions, e.g. obtained by leaching by chemical processes
    • 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

Definitions

  • the present invention relates to the purification of zinc-bearing materials, more particularly but not necessarily exclusively to zinc-bearing aqueous solutions.
  • Zn ores for example sphalerite
  • Mn manganese
  • MnO 2 Although some relatively small amounts of Mn are generally acceptable in a Zn electrolyte, for example, excessive quantities can create problems, since the Mn is oxidized at the anode in the form of MnO 2 , some of which falls at the bottom of the cell and must be periodically removed. Greater concentrations of MnO, can lead to significant reductions in electrolytic efficiency.
  • Another solution proposed by the prior art is to oxidize Mn 2* to Mn 4+ so that MnO 2 can be removed by precipitation at a pH where Zn 2+ is soluble.
  • Air and oxygen gas are typically used as oxidants in this case but they are generally uneconomically slow.
  • Peroxide or stronger oxidants, such as Caro's acid or ozone, are in many cases too expensive.
  • US Patent 2,816,819 to Wallis et al. discloses a system which uses SO 2 /Air to precipitate iron from a cobalt- or a nickel-bearing solution.
  • Canadian Patent 935,650 discloses a technique by which a mixture of SO 2 /Air is used to precipitate a number of impurities from a cobalt or a nickel solution.
  • neither reference is concerned with techniques for reducing impurities from Zn-bearing materials.
  • the invention involves a process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting the material to mixture of SO 2 and oxygen, at conditions sufficient to oxidize the manganese constituent.
  • the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of the zinc constituent.
  • Figure 1 is a plot of precipitation for Mn and Zn according to pH
  • Figure 2 is a plot of precipitation using SO 2 /O 2 mixture as an oxidant
  • the invention involves a process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting the material to mixture of SO 2 and oxygen, at conditions sufficient to oxidize the manganese constituent.
  • the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of the zinc constituent.
  • the process is carried out at a pH between about 3 and about 5, more preferably between 3 and 4. Still more preferably, the pH is 3.
  • the pH is higher than 5, for example up to 7, at least some residual Zn may be precipitated with the Mn.
  • the pH limit of 4 is significant because, as the following examples illustrate, residual Zn has been found to appear in the precipitate at a pH value above 4 while there appears to be no Zn co-precipitate at pH values below 4. Therefore, it may be desirable, in some circumstances, to maintain the reaction at the lower end of the pH range, that is in the vicinity of pH 3 in order to minimize the likelihood of a Zn co-precipitate. This route may also be enhanced by maintaining a distribution of nucleation sites in the reaction, such as MnO 2 crystals.
  • the oxygen may be in the form of O 2 or air or a mixture of both.
  • the process occurs at a temperature ranging from about 40 to about 80°C, more preferably at a temperature ranging from 50 to 80°C, still more preferably at a temperature ranging from 58 to 78°C.
  • the process may be carried out at about 70°C or, alternatively, at about 60°C.
  • the SO 2 is at a concentration from about 0.5% to 10%, with the balance O 2 gas, more preferably from 1 to 8%, still more preferably at a concentration from 2 to 3%.
  • the SO 2 is preferably at a concentration ranging from about 0.1% to 2%, with the balance being Air, more preferably from about 0.2 to 1.4%, still more preferably from about 0.4 to 0.6%.
  • the concentration may be about 0.5%.
  • the zinc material may be in a number of forms including an aqueous solution, such as a leach solution or an electrolyte solution.
  • the present process is beneficial in that it makes use of a relatively inexpensive and plentiful oxidant, a gas mixture of O 2 /SO 2 , or alternatively Air/SO 2 , or still alternatively 100% pure Air can be used together with equivalent amounts of SO 2 , preferably added as SO 2 in a gaseous or liquid form, or added as a constituent in a solution containing, for example, sodium metabisulphite, ammonium metabisulphite, potassium metabisulphite or other suitable forms of metabisulphite.
  • a solution containing 5 g/L Mn as MnSO 4 was sparged with a mixture of SO 2 and O 2 at different pH levels. The amount of Mn removed at each pH is shown in figure 2.
  • the Mn is removed from solution at pH levels ranging from about 3 to 5. However, in the region from about 3 to 4, the Mn is removed from solution while the Zn is soluble and therefore remains in solution.
  • a solution containing 18 g/L Mn as MnSO 4 was sparged at 60°C and at a pH of 6.5 with SO 2 /O 2 mixtures containing 2% (v/v) SO 2 . After one hour, 25% of the manganese had precipitated. After 2 hours, 57% of the Mn had precipitated and after 4 hours, 99.5% of the Mn had precipitated.

Landscapes

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

Abstract

Disclosed herein is a process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting the material to a first oxidation mixture of SO2 and oxygen, at conditions sufficient to oxidize the manganese constituent and wherein the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of said zinc constituent.

Description

PURIFICATION OF ZINC-BEARING MATERIAL SOLUTIONS CONTAINING MANGANESE
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention relates to the purification of zinc-bearing materials, more particularly but not necessarily exclusively to zinc-bearing aqueous solutions.
2. DESCRIPTION OF THE RELATED ART
Some zinc (Zn) ores, for example sphalerite, contain high levels of manganese (Mn) that cannot be separated using conventional mineral processing techniques, since the Mn is present in the crystal lattice. When Zn sulphides containing Mn impurities are roasted and then leached, they can. in some cases, produce leach solutions or electrolyte solutions containing unreasonably high levels of Mn.
Although some relatively small amounts of Mn are generally acceptable in a Zn electrolyte, for example, excessive quantities can create problems, since the Mn is oxidized at the anode in the form of MnO 2, some of which falls at the bottom of the cell and must be periodically removed. Greater concentrations of MnO, can lead to significant reductions in electrolytic efficiency.
It is generally known in the prior art that precipitating zinc and manganese together, using sodium carbonate or lime as naturalizing agent, can be carried out at 70°C and at pH values between 5 and 7. However, in this case, zinc begins to precipitate before manganese and therefore most of the zinc would be precipitated with manganese which is obviously not acceptable, as shown in figure 1.
Another solution proposed by the prior art is to oxidize Mn2* to Mn4+ so that MnO2 can be removed by precipitation at a pH where Zn2+ is soluble. Air and oxygen gas are typically used as oxidants in this case but they are generally uneconomically slow. Peroxide or stronger oxidants, such as Caro's acid or ozone, are in many cases too expensive.
US Patent 2,816,819 to Wallis et al. discloses a system which uses SO2/Air to precipitate iron from a cobalt- or a nickel-bearing solution. Canadian Patent 935,650 discloses a technique by which a mixture of SO2/Air is used to precipitate a number of impurities from a cobalt or a nickel solution. However, neither reference is concerned with techniques for reducing impurities from Zn-bearing materials.
It is an object of the present invention to provide an improved method to remove at least a portion of Mn from Zn-bearing materials.
SUMMARY OF THE INVENTION
Briefly stated, the invention involves a process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting the material to mixture of SO2 and oxygen, at conditions sufficient to oxidize the manganese constituent.
Preferably, the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of the zinc constituent.
BRIEF DESCRIPTION OF THE DRAWINGS
Several preferred embodiments of the present invention will now be described, by way of example only, with reference to the appended drawing in which:
Figure 1 is a plot of precipitation for Mn and Zn according to pH;
Figure 2 is a plot of precipitation using SO2/O2 mixture as an oxidant; DESCRIPTION OF THE PREFERRED EMBODIMENTS
Briefly stated, the invention involves a process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting the material to mixture of SO2 and oxygen, at conditions sufficient to oxidize the manganese constituent.
Preferably, the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of the zinc constituent.
Preferably, the process is carried out at a pH between about 3 and about 5, more preferably between 3 and 4. Still more preferably, the pH is 3.
If the pH is higher than 5, for example up to 7, at least some residual Zn may be precipitated with the Mn. The higher the pH in this range, the greater the quantity of Zn being precipitated with Mn. In this case, it may be feasible either to process the Mn subsequently with the residual Zn in place or alternatively to subject the co-precipitate to a mildly acidic solution (such as at a pH of 3 to 4) to re-dissolve the residual zinc.
The pH limit of 4 is significant because, as the following examples illustrate, residual Zn has been found to appear in the precipitate at a pH value above 4 while there appears to be no Zn co-precipitate at pH values below 4. Therefore, it may be desirable, in some circumstances, to maintain the reaction at the lower end of the pH range, that is in the vicinity of pH 3 in order to minimize the likelihood of a Zn co-precipitate. This route may also be enhanced by maintaining a distribution of nucleation sites in the reaction, such as MnO2 crystals.
The oxygen may be in the form of O2 or air or a mixture of both.
Preferably, the process occurs at a temperature ranging from about 40 to about 80°C, more preferably at a temperature ranging from 50 to 80°C, still more preferably at a temperature ranging from 58 to 78°C. For example, the process may be carried out at about 70°C or, alternatively, at about 60°C.
It may also be desirable, in some cases, to raise the temperature above 80°C, for example to an upper limit of about 130°C or higher in order to increase the reaction kinetics of the process, though this would need to be done under pressure, depending on the chosen temperature. For example, a temperature of 130°C would require a pressure of about 50 psi.
Preferably, in the case where the oxygen is present in the form of O2 gas, the SO2 is at a concentration from about 0.5% to 10%, with the balance O2 gas, more preferably from 1 to 8%, still more preferably at a concentration from 2 to 3%.
In the case where the oxygen is present in air, the SO2 is preferably at a concentration ranging from about 0.1% to 2%, with the balance being Air, more preferably from about 0.2 to 1.4%, still more preferably from about 0.4 to 0.6%. For example, the concentration may be about 0.5%.
The zinc material may be in a number of forms including an aqueous solution, such as a leach solution or an electrolyte solution.
The present process is beneficial in that it makes use of a relatively inexpensive and plentiful oxidant, a gas mixture of O2/SO2, or alternatively Air/SO2, or still alternatively 100% pure Air can be used together with equivalent amounts of SO2, preferably added as SO2 in a gaseous or liquid form, or added as a constituent in a solution containing, for example, sodium metabisulphite, ammonium metabisulphite, potassium metabisulphite or other suitable forms of metabisulphite.
Embodiments of the present invention will be described with reference to the following Examples which are presented for illustrative purposes only and are not intended to limit the scope of the invention.
EXAMPLE 1
A solution containing 5 g/L Mn as MnSO4 was sparged with a mixture of SO2 and O2 at different pH levels. The amount of Mn removed at each pH is shown in figure 2.
A comparison can be made between the precipitation of pH's of manganese oxidized with SO2/O2 as shown in figure 2 with the precipitation of zinc as shown in figure 1. The Mn is removed from solution at pH levels ranging from about 3 to 5. However, in the region from about 3 to 4, the Mn is removed from solution while the Zn is soluble and therefore remains in solution.
EXAMPLE 2
A solution containing 18 g/L Mn as MnSO4 was sparged at 60°C and at a pH of 6.5 with SO2/O2 mixtures containing 2% (v/v) SO2. After one hour, 25% of the manganese had precipitated. After 2 hours, 57% of the Mn had precipitated and after 4 hours, 99.5% of the Mn had precipitated.

Claims

1. A process for removing at least a portion of a manganese constituent from a zinc-bearing material, comprising the step of subjecting said material to a first oxidation mixture of SO2 and oxygen, at conditions sufficient to oxidize said manganese constituent.
2. A process as defined in claim 1 wherein the material is maintained at a pH sufficient to precipitate manganese while minimizing precipitation of said zinc constituent.
3. A process as defined in claim 2 wherein said pH is between about 3 and about 5.
4. A process as defined in claim 3 wherein said pH is between 3 and 4.
5. A process as defined in claim 4 wherein said pH is 3.
6. A process as defined in claim 1 wherein said oxygen is in the form of O2.
7. A process as defined in claim 6 wherein said oxidation mixture includes Air.
8. A process as defined in claim 7 wherein steps (a) and (c) occur at a temperature ranging from about 40 to about 80°C.
9. A process as defined in claim 8 wherein steps (a) and (c) occur at a temperature ranging from 50 to 80°C.
10. A process as defined in claim 9 wherein steps (a) and (c) occur at a temperature ranging from 58 to 78°C.
1 1. A process as defined in claim 10 wherein steps (a) and (c) occur at about 70°C.
12. A process as defined in claim 10 wherein steps (a) and (c) occur at about 60°C.
13. A process as defined in claim 6 wherein said SO2 is at a concentration from 0.5% to 10%, with the balance O2 gas.
14. A process as defined in claim 13 wherein said SO2 is at a concentration from 1 to 8%.
15. A process as defined in claim 14 wherein SO2 is at a concentration from 2 to 3%.
16. A process as defined in claim 7 wherein SO2 is at a concentration from 0.1% to 2%, with the balance being Air.
17. A process as defined in claim 16 wherein said SO2 is at a concentration from 0.2 to 1.4%.
18. A process as defined in claim 17 wherein SO2 is at a concentration from 0.4 to 0.6%.
19. A process as defined in claim 1 wherein said zinc bearing material is a leach solution.
20. A process as defined in claim 1 wherein said zinc material is an electrolyte solution.
PCT/CA2000/000352 1999-04-09 2000-04-05 Purification of zinc-bearing material solutions containing manganese WO2000061826A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU35479/00A AU3547900A (en) 1999-04-09 2000-04-05 Purification of zinc-bearing material solutions containing manganese
US09/977,917 US20020083795A1 (en) 1999-04-09 2001-10-09 Purification of zinc bearing material solutions containing manganese

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA2,268,496 1999-04-09
CA002268496A CA2268496A1 (en) 1999-04-09 1999-04-09 Purification of zinc materials

Publications (1)

Publication Number Publication Date
WO2000061826A1 true WO2000061826A1 (en) 2000-10-19

Family

ID=4163451

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CA2000/000352 WO2000061826A1 (en) 1999-04-09 2000-04-05 Purification of zinc-bearing material solutions containing manganese

Country Status (5)

Country Link
US (1) US20020083795A1 (en)
AU (1) AU3547900A (en)
CA (1) CA2268496A1 (en)
WO (1) WO2000061826A1 (en)
ZA (1) ZA200109183B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001048255A1 (en) * 1999-12-23 2001-07-05 Noranda Inc. Method to control manganese in zinc leach circuits
WO2003023077A1 (en) * 2001-09-13 2003-03-20 Intec Ltd Zinc recovery process

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2816819A (en) * 1949-09-07 1957-12-17 Int Nickel Co Process of removing ferrous sulfate from sulfate solutions containing nickel and/or cobalt
US3685965A (en) * 1968-12-03 1972-08-22 Norddeutsche Affinerie Redox precipitation of nonferrous heavy metals from aqueous solution
US4067789A (en) * 1975-07-09 1978-01-10 Newmont Exploration Limited Process for manganese removal from zinc metal bearing solutions
US4290866A (en) * 1978-12-20 1981-09-22 Sherritt Gordon Mines Limited Removal of manganese ions from zinc and manganese containing solutions
SU947055A1 (en) * 1981-02-06 1982-07-30 Всесоюзный Ордена Трудового Красного Знамени Научно-Исследовательский Горнометаллургический Институт Цветных Металлов Method for purifying zinc electrolyte from impurities
US4439288A (en) * 1983-07-11 1984-03-27 Exxon Research & Engineering Company Process for reducing Zn consumption in zinc electrolyte purification
SU1411348A1 (en) * 1986-10-08 1988-07-23 Северо-Кавказский горно-металлургический институт Method of cleaning zinc solutions of iron (ii) and manganese (ii)

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2816819A (en) * 1949-09-07 1957-12-17 Int Nickel Co Process of removing ferrous sulfate from sulfate solutions containing nickel and/or cobalt
US3685965A (en) * 1968-12-03 1972-08-22 Norddeutsche Affinerie Redox precipitation of nonferrous heavy metals from aqueous solution
US4067789A (en) * 1975-07-09 1978-01-10 Newmont Exploration Limited Process for manganese removal from zinc metal bearing solutions
US4290866A (en) * 1978-12-20 1981-09-22 Sherritt Gordon Mines Limited Removal of manganese ions from zinc and manganese containing solutions
SU947055A1 (en) * 1981-02-06 1982-07-30 Всесоюзный Ордена Трудового Красного Знамени Научно-Исследовательский Горнометаллургический Институт Цветных Металлов Method for purifying zinc electrolyte from impurities
US4439288A (en) * 1983-07-11 1984-03-27 Exxon Research & Engineering Company Process for reducing Zn consumption in zinc electrolyte purification
SU1411348A1 (en) * 1986-10-08 1988-07-23 Северо-Кавказский горно-металлургический институт Method of cleaning zinc solutions of iron (ii) and manganese (ii)

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Section Ch Week 198324, Derwent World Patents Index; Class M25, AN 1983-58227K, XP002144647 *
DATABASE WPI Section Ch Week 198904, Derwent World Patents Index; Class M25, AN 1989-031539, XP002144646 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001048255A1 (en) * 1999-12-23 2001-07-05 Noranda Inc. Method to control manganese in zinc leach circuits
US6391270B1 (en) * 1999-12-23 2002-05-21 Noranda Inc. Method for removing manganese from acidic sulfate solutions
WO2003023077A1 (en) * 2001-09-13 2003-03-20 Intec Ltd Zinc recovery process
AP1757A (en) * 2001-09-13 2007-07-25 Intec Ltd Zinc recovery process.
CN1332046C (en) * 2001-09-13 2007-08-15 英泰克有限公司 Zinc recovery process
AU2002328671B2 (en) * 2001-09-13 2008-11-20 Intec Ltd Zinc recovery process
US7465334B2 (en) 2001-09-13 2008-12-16 Intec Ltd. Zinc recovery process

Also Published As

Publication number Publication date
US20020083795A1 (en) 2002-07-04
CA2268496A1 (en) 2000-10-09
ZA200109183B (en) 2002-07-31
AU3547900A (en) 2000-11-14

Similar Documents

Publication Publication Date Title
US11316208B2 (en) Process for recycling cobalt and nickel from lithium ion batteries
US9017640B2 (en) Method for producing high-purity nickel surface
CA1141172A (en) Removal of manganese ions from zinc and manganese containing solutions
US5932086A (en) Process for making manganese
US4071421A (en) Process for the recovery of zinc
JP5495418B2 (en) Method for recovering manganese
US10995413B2 (en) Sulfide recycling in manganese production
JP6996723B1 (en) Metal recovery method from lithium-ion batteries
ZA200506902B (en) Method for removing thallium from a zinc-containing solution
CA2366294A1 (en) Methods of purifying cobalt
US20020083795A1 (en) Purification of zinc bearing material solutions containing manganese
US4355009A (en) Separative treatment of zinc-bearing flue dust
JP2006144102A (en) Method for recovering nickel and/or cobalt sulfide
US4175014A (en) Cathodic dissolution of cobaltic hydroxide
US4885144A (en) Process for purifying molybdenum
US5403571A (en) Purification of elemental sulphur
GB2394469A (en) Removing manganese from a cobalt solution
US4548793A (en) Electrochemical elimination of nickel from lead containing chloride solutions
KR20240071152A (en) Method for Recovering High Purity MnO2 from Manganese Dust
CN118359230A (en) Treatment method of manganese-copper mixed solution
JPH10140258A (en) Removing method of impurity from chlorine leaching liquid of nickel
WO2023026931A1 (en) Manganese removal method and ferric oxide production method
JPH055132A (en) Method for recovering cadmium
JPS5943535B2 (en) Method for removing manganese from acidic solutions containing nickel and cobalt
RU2004111286A (en) ZINC METHOD

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
ENP Entry into the national phase

Ref country code: US

Ref document number: 2001 977917

Date of ref document: 20011009

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 35479/00

Country of ref document: AU

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP