AU4067002A - Polymer flocculant for sulfuric acid leaching separation in valuable metal recovery method, and valuable metal recovery method using the same polymer flocculant - Google Patents
Polymer flocculant for sulfuric acid leaching separation in valuable metal recovery method, and valuable metal recovery method using the same polymer flocculant Download PDFInfo
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- AU4067002A AU4067002A AU40670/02A AU4067002A AU4067002A AU 4067002 A AU4067002 A AU 4067002A AU 40670/02 A AU40670/02 A AU 40670/02A AU 4067002 A AU4067002 A AU 4067002A AU 4067002 A AU4067002 A AU 4067002A
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- polymer flocculant
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- 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
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Description
AUSTRALIA
Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicants: PACIFIC METALS CO., LTD.
DAI-ICHI KOGYO SEIYAKU CO., LTD.
Invention Title: POLYMER FLOCCULANT FOR SULFURIC ACID LEACHING SEPARATION IN VALUABLE METAL RECOVERY METHOD, AND VALUABLE METAL RECOVERY METHOD USING THE SAME POLYMER
FLOCCULANT
The following statement is a full description of this invention, including the best method of performing it known to me/us:
SPECIFICATION
Of HIROMASA YAKUSHIJI, SEIJI ITO, YOSHIAKI OKAYAMA and YOSHIYUKI MORI For: POLYMER FLOCCULANT FOR SULFURIC ACID LEACHING SEPARATION IN VALUABLE METAL RECOVERY METHOD, AND VALUABLE METAL RECOVERY METHOD USING THE SAME POLYMER FLOCCULANT BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a polymer flocculant (a flocculant for separation step of sulfuric acid leaching solution) to be used for removing leaching residue by flocculation in a method for valuable metal recovery by extracting valuable metals such as nickel, cobalt, manganese and the like from an oxide ore containing the valuable metals by leaching with sulfuric acid and after flocculation separation of the leaching residue, recovering these valuable metals as sulfides and carbonates. Also, the present invention relates to a valuable metal recovery method using the foregoing polymer flocculant capable O0of efficiently flocculating and separating leaching residue after the sulfuric acid leaching from the valuable metal dissolving solution.
PRIOR ART A method for recovering nickel and cobalt from an nickel-and cobalt-containing oxide ore by a sulfuric acid solution is well known according to the description of US Patent No. 2,872,306, Journal of Metals, March, 1960, p20 6 and the like. Further, as a conventional method for extracting nickel and cobalt by leaching with sulfuric acid, there are a method carried out under atmospheric pressure and a method carried out under a high temperature high pressure condition and in both cases, since other metals such as iron and the like coexisting in the oxide ore are simultaneously leached, there occurs a problem that the use amount of sulfuric acid is increased or the like.
Hence, a process for efficiently producing nickel sulfide and cobalt sulfide within a short time is proposed, wherein the process comprises a high temperature pressurizing extraction method capable of relatively suppressing dissolution of other metals such as iron and the like and reaction with an alkaline sulfide compound under moderate conditions (a normal pressure, 100 0 C or lower) after extraction without using an autoclave.
In the above process, it is also important to efficiently flocculate and separate leaching residue from a valuable metal dissolving solution after sulfuric acid leaching from an economical point of view. However, a commonly used polyacrylamide, acrylamideacrylic acid copolymer and the like for the flocculation treatment in the industrial wastewater were insufficient in the flocculation and separation performance.
The flocculation and separation of the leaching residue from QOa valuable metal dissolving solution after sulfuric acid leaching is carried out under severe conditions of a high temperature and a high acidity of sulfuric acid and a polyacrylamide, an acrylamide-acrylic acid copolymer and the like, which are widely used in flocculation treatment of general industrial wastewater, were insufficient in flocculation. It was therefore required to urgently develop a chemical agent effectively functioning as a flocculant.
SUMMARY OF THE INVENTION The purpose of the present invention is to provide a polymer flocculant having the following composition and excellent in the acid stability at a high temperature and flocculation capability in the case of flocculating and separating the leaching residue suspended and dispersed in a pressurized leached slurry with a polymer flocculant.
Also, the present invention is to provide a method capable of efficiently recovering valuable metals with scarce impurity contamination from an oxide ore containing valuable metals such as nickel, cobalt, manganese and the like by using such a polymer flocculant.
The polymer flocculant of the present invention is to be used for removal of sulfuric acid leaching residue in valuable metal recovery process by extracting valuable metals from an oxide ore by sulfuric acid leaching, and after flocculation and separation of the leached slurry, recovering the valuable metals as sulfides and carbonates. It is characterized in that the polymer flocculant is a water-soluble high molecular weight copolymer having a composition containing i) 2.5 to 4O by mole of a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and ii) 50 by X mole or more of (meth)acrylamide or its derivative and having the viscosity of 5 to 40 mPa s in form of an aqueous salt solution containing 0.2% of this high molecular weight copolymer and 4% of NaCl.
Incidentally, the foregoing viscosity is measured using Brookfield type viscometer Rotor No. 1 in conditions of 60 rpm at 30 C Further, in the polymer flocculant of the present invention having the above-described characteristic, the foregoing sulfonic acid group-containing, copolymerizable and water-soluble monomer is 2-acrylamido-2-methylpropanesulfonic acid or its salt.
Further, in the polymer flocculant of the present invention having the above-described characteristic, the foregoing sulfonic acid group-containing, copolymerizable and water-soluble monomer is vinylsulfonic acid or its salt.
Further, in the polymer flocculant of the present invention having the above-described characteristic, the foregoing polymer flocculant has a composition further containing one or more kinds of i) a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and ii) (meth)acrylamide or its derivative, and iii) copolymerizable vinyl monomer compounds.
Furthermore, in the polymer flocculant of the present invention having the above-described characteristic, the foregoing vinyl monomer compound is selected from acrylic acid, methacrylic acid and their salts and alkyl alcohol esters, N-alkyl-substituted acrylamides, and vinyl acetamide.
Furthermore, the present invention is a valuable metal recovery method comprising a first step of finely pulverizing an oxide ore containing mainly valuable metals and concentrating the obtained cZ aqueous slurry by precipitation and a second step of leaching and separating a concentrated slurry obtained in the first step in acidic condition of sulfuric acid and is characterized in that the second step is carried out using a polymer flocculant for the sulfuric acid leaching process in a valuable metal recovery method is a water-soluble high molecular weight copolymer having a composition containing i) 2.5 to by mole of a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and ii) 50 by mole or more of (meth)acrylamide or its derivative and having the viscosity of 5 to mPa *s in form of an aqueous salt solution containing 0.2% of the water-soluble high molecular weight copolymer and 4% of NaC1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS At first, a polymer flocculant for the sulfuric acid leaching process of the present invention will be described.
The polymer flocculant is to be used for flocculation and separation of leached slurry after producing a slurry of an oxide ore containing mainly nickel, cobalt, manganese and the like as valuable metals and leaching (extracting) the valuable metals by adding sulfuric acid, and after the flocculation and separation, nickel and cobalt are recovered in form of sulfides by sulfurization (addition of an alkaline sulfide compound) and further manganese is recovered in form of a carbonate by carbonation (addition of a carbonate).
The polymer flocculant of the present invention is a watersoluble high molecular weight copolymer has a composition containing, as essential constituent components, i) 2.5 to 40 by mole, preferably to 40 by mole, of a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and ii) 50 by mole or more of O) (meth)acrylamide or its derivative and additionally, as another optional constituent component, a vinyl monomer copolymerizable with these two compounds, and such a copolymer can be obtained by a common copolymerization reaction.
As the sulfonic acid group-containing, copolymerizable and 25 water-soluble monomer, 2-acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, styrenesulfonic acid, allylsulfonic acid and their salts can be exemplified and as their salts, for example, alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts can be exemplified. Among them, 2-acrylamido-2-methylpropanesulfonic acid alkali metal salts and ammonium salt, or vinylsulfonic acid alkali metal salts and ammonium salt are preferable. Incidentally, as the salts, alkali metal salts, especially sodium salts, are industrially advantageous to be used.
Also, as the (meth)acrylamide derivatives, N-alkyl-substituted (meth)acrylamide can be exemplified.
The polymer flocculant having the foregoing composition has the viscosity of 5 to 40 mPa *s in form of an aqueous salt solution C1 containing 0.2% of this copolymer and 4% of NaCl.
In this case, if the ratio of the sulfonic acid groupcontaining, copolymerizable and water-soluble monomer or its salt in the composition is less than 2.5 by mole, the necessary amount of the flocculant is increased because flocs become easy to be broken and on the contrary, if the ratio is more than 40 by mole, the flocs tend to become soft and the sedimentation effect tends to be deteriorated to result in insufficient flocculation and separation capability. Also, in the case of the ratio of the (meth)acrylamide or its derivative, which is another component, in the composition is 50 by mole or lower, (0 insufficient flocculation and separation capability is obtained.
Incidentally, in the case of using the copolymer having the viscosity of less than 5 mPa *s in form of an aqueous salt solution NaC1 solution) containing 0.2% of the foregoing water-soluble copolymer and 4% of NaCl, the formed flocs become small and easy to be broken and in the case of using the copolymer having the viscosity of higher than 40 mPa s, the flocs tend to become soft and the sedimentation effect tends to be deteriorated and further, the copolymer itself is difficult to be produced.
Generally, the polymer flocculant of the present invention is used in form of an aqueous 0.1 to 0.2 solution by being added to a sulfuric acid leaching slurry and the optimum dosage is 0.01 to 0.20%, preferably 0.02 to 0.10%, to the solid matter (ore) in the slurry.
In the present invention, the foregoing water-soluble high copolymer may further contain optional components other than the above-described essential constituent components and as these optional components, any can be used without specific restrictions if it reacts I with the foregoing components i) and ii) to become a water-soluble high copolymer, yet preferable examples are the compounds selected from vinyl monomer compounds are acrylic acid, methacrylic acid and their salts, or alkyl alcohol ester, maleic acid, itaconic acid and their salts, and vinyl acetamide.
The reason for the excellent flocculation performance of the polymer flocculant of the invention is supposed as follows.
That is, in the case of polyacrylamide and an acrylamideacrylic acid copolymer which are used as common flocculants for suspended wastewater, generally, the dissociation of the carboxylic Do acid and the anionization are suppressed in strongly acidic condition and accordingly, the flocculation performance is lowered, whereas in the case of the water-soluble polymer flocculant of the present invention, it is supposed that ionization dissociation is sufficient even in the strongly acidic condition and the anionic charge is bonded c 5 with the cationic charge of the suspended fine particle to result in excellent flocculation performance.
Next, a valuable metal recovery process of the present invention will be described. The process comprises a first step of finely pulverizing an oxide ore containing mainly the foregoing valuable metals and getting it's slurry and a second step of leaching in acidic condition of sulfuric acid and separating slurry at the time of the flocculation and separation of the leached slurry from the valuable metal dissolving solution, the polymer flocculant having the foregoing composition and the molecular weight with the defined viscosity is used.
In the recovery method of the present invention, the foregoing polymer flocculant is added at a ratio of 0.01 to 0.20%, preferably 0.02 to 0.10%, to the ore and in such a case, economical and efficient flocculation and solid-liquid separation can be achieved. Incidentally, the pH at the time of the leaching with sulfuric acid in the second step is generally in the range from 0.5 to 4.
Hereinafter, the present invention will be described in details along with examples of the present invention, the present invention is not restricted to these examples.
DESCRIPTION OF THE PREFERRED EXAMPLE EXAMPLE 1 c)Q As sample flocculants, flocculants (No.1 to No. 10) were produced from the monomer compositions in form of salt solutions with the respective viscosity values as shown in following Table 1 by respectively known polymerization methods.
In Table 1, the reference character AAm denotes acrylamide; AAcNa denotes sodium acrylate; AMPS denotes sodium salt 2-acrylamido- 2-methylpropanesulfonate; VS denotes sodium salt vinylsulfonate; MAAm denotes methacrylamide; and DAA denotes dimethylaminoethyl acrylate and the viscosity values shown in Table 1 were measured using Brookfield type viscometer Rotor No. 1 in conditions of 60 rpm at 30 -C.
Table 1 Sample flocculants Raw material monomer composition Salt soluti- No. Flocculant on viscosity AAm AAcNa AMPS VS MAAm DAA NaCl mol% mol% mol% mol% mol% mol% mPa* S 1 AAm-AMPS 90 0 10 0 0 0 12 copolymer (1) 2 AAm-AMPS 70 0 30 0 0 0 1 copolymer 3 AAm-AMPS-AAcNa 70 5 25 0 0 0 copolymer U AAm-AMPS-MAAm 70 0 25 0 5 0 copolymer (4) AAm-VS copolymer 95 0 0 5 0 0 12 6 AAm-AMPS 98 0 2 0 0 0 copolymer 7 AAm-AMPS 40 0 60 0 0 0 3 copolymer (6) 8 Polyacrylamide 100 0 0 0 0 0 17 AAm-AAcNa copolymer I 1 1 r r AAm-DAA copolymer 0 0 0 19 30 Remarks: Inventive products (No.
1 to No.- Comparative products (No. 6 to No. On the other hand, as a nickel ore slurry, nickel ore (the Ni content of 0.86%, the particle diameter of 2 mm or smaller) was mixed with a diluted sulfuric acid and treated at 240 °C for 1 hour in an autoclave to obtain a slurry. The slurry obtained in such a manner had a concentration of 210 g/l and pH 1.1.
Flocculation testing method: A messcylinder of 100 ml capacity was charged with 90 ml of the foregoing nickel ore slurry and 10 ml of an aqueous solution of 0.1% of each flocculant (No. 1 to No. 10) described in Table 1, and plugged and turned upside down 10 times to carry out flocculation.
O0 After that, the size of the formed flocs was evaluated with visual observation and at the same time the messcylinder was kept still for minutes to measure the volume of the sediments.
The results of the test were shown in the following Table 2.
Table 2 Test results Dosage Diameter of Sediment No. Flocculant flocs volume to ore mm ml 1 AAm-AMPS 0.053 3 57 copolymer (1) 2 AAm-AMPS 0.053 4 52 copolymer (2) 3 AAm-AMPS-AAcNa 0.053 3 57 copolymer (3) S AAm-AMPS-MAAm 0.053 4 52 copolymer (4) AAm-VS copolymer 0.053 3 64 6 AAm-AMPS copolymer 0.053 1 96 7 AAm-AMPS copolymer 0.053 1 98 (6) 8 Polyacrylamide 0.053 1 or smaller 99 9 AAm-AAcNa 0.053 1 or smaller 99 copolymer AAm-DAA copolymer 0.053 1 or smaller 99 11 No addition 0.0 No 100 flocculation As shown in the foregoing Table 2, the polymer flocculants of the present invention containing a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and (meth)acrylamide or its derivative in a specified constitutional ratio are excellent in the flocculation performance. By applying said flocculants, solid-liquid separation can be carried out efficiently in a short time. These flocculants of the present invention are good in performance stability to the acid even at a high temperature.
Further, in the case of employing the valuable metal recovery method of the present invention using such polymer flocculants, the Svaluable metal can be recovered from an oxide ore containing valuable metals such as nickel, cobalt, manganese and the like with good efficiency and little impurity contamination.
For the purposes of this specification it will be clearly understood that the word "comprising" means "including but not limited to", and that the word "comprises" has a corresponding meaning.
It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.
Claims (6)
1. A polymer flocculant to be used for flocculation removal of sulfuric acid leaching residue in a method of valuable metal recovery by extracting valuable metals from an oxide ore containing mainly said valuable metals by sulfuric acid leaching, and after flocculation and separation of the leaching residue, recovering said valuable metals as sulfides and carbonates, wherein the polymer flocculant is a water- soluble high molecular weight copolymer having a composition containing IC) i) 2.5 to 40 by mole of a sulfonic acid group-containing, copoly- merizable and water-soluble monomer or its salt and ii) 50 by mole or more of (meth)acrylamide or its derivative and having the viscosity of to 40 mPa *s in form of an aqueous salt solution containing 0.2% of the copolymer and 4% of NaCl.
2. The polymer flocculant for the sulfuric acid leaching process in a valuable metal recovery method according to claim 1, wherein said sulfonic acid group-containing, copolymerizable and water-soluble monomer is 2-acrylamido-2-methylpropanesulfonic acid or its salt. o)0
3. The polymer flocculant for the sulfuric acid leaching process in a valuable metal recovery method according to claim 1, wherein said sulfonic acid group-containing, copolymerizable and water-soluble monomer is vinylsulfonic acid or its salt.
4. The polymer flocculant for the sulfuric acid leaching process in a valuable metal recovery method according to any one of claim 1 to claim 3, wherein said polymer flocculant has a composition further containing one or more kinds of i) a sulfonic acid group- containing, copolymerizable and water-soluble monomer or its salt, ii) (meth)acrylamide or its derivative, and iii) copolymerizable vinyl monomer compounds.
The polymer flocculant for the sulfuric acid leaching process in a valuable metal recovery method according to claim 4, wherein said vinyl monomer compound is selected from acrylic acid, methacrylic acid, their salts and alkyl alcohol esters, N-alkyl- substituted acrylamides, and vinyl acetamide.
6. A valuable metal recovery method comprising a first step of finely pulverizing an oxide ore containing mainly valuable metals and getting the aqueous slurry and a second step of leaching (O in acidic condition of sulfuric acid and separating the obtained slurry to valuable liquid to be recovered and residue to be discharged, wherein a polymer flocculant is used as a flocculant to enhance the solid-liquid separation treatment effect in the second step and said polymer flocculant is a water-soluble high molecular weight copolymer having a composition containing i) 2.5 to 40 by mole of a sulfonic acid group-containing, copolymerizable and water-soluble monomer or its salt and ii) 50 by mole or more of (meth)acrylamide or its derivative and having the viscosity of 5 to 40 mPa *s in form of an aqueous salt solution containing 0.2% of the copolymer and 4% o of NaCl. Dated this 16th day of May 2002 PACIFIC METALS CO.. LTD. and DAI-ICHI KOGYO SEIYAKU CO., LTD By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001147226A JP2002339020A (en) | 2001-05-17 | 2001-05-17 | High molecular flocculation agent for sulfuric acid leaching separation process in valuable metal recovery method and valuable metal recovery method using the same |
| JP2001-147226 | 2001-05-17 |
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| Publication Number | Publication Date |
|---|---|
| AU4067002A true AU4067002A (en) | 2002-11-21 |
| AU775649B2 AU775649B2 (en) | 2004-08-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| AU40670/02A Expired AU775649B2 (en) | 2001-05-17 | 2002-05-16 | Polymer flocculant for sulfuric acid leaching separation in valuable metal recovery method, and valuable metal recovery method using the same polymer flocculant |
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| JP (1) | JP2002339020A (en) |
| AU (1) | AU775649B2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5141781B2 (en) * | 2011-01-25 | 2013-02-13 | 住友金属鉱山株式会社 | Method for producing ore slurry |
| ES2611933T3 (en) | 2012-08-10 | 2017-05-11 | Basf Se | Metal leaching and recovery process |
| CN103173624B (en) * | 2013-03-06 | 2014-09-03 | 昆明理工大学 | Method for recovery germanium from germanium-containing flue dust |
| JP5725143B2 (en) * | 2013-12-05 | 2015-05-27 | 住友金属鉱山株式会社 | Neutralization treatment plant |
| JP6984191B2 (en) * | 2017-06-20 | 2021-12-17 | 住友金属鉱山株式会社 | Solid-liquid separation method of nickel high-pressure leachate residue |
| CN111663043B (en) * | 2020-04-28 | 2022-01-18 | 西北矿冶研究院 | Method for enriching and recovering valuable metals from acidic sewage in nonferrous smelting process |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4342653A (en) * | 1979-02-15 | 1982-08-03 | American Cyanamid Company | Process for the flocculation of suspended solids |
| US4587108A (en) * | 1982-10-07 | 1986-05-06 | Allied Colloids Limited | Flocculation of acid leach slurries |
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- 2001-05-17 JP JP2001147226A patent/JP2002339020A/en active Pending
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| Publication number | Publication date |
|---|---|
| AU775649B2 (en) | 2004-08-12 |
| JP2002339020A (en) | 2002-11-27 |
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| HB | Alteration of name in register |
Owner name: PACIFIC METALS CO., LTD. Free format text: FORMER NAME(S): DIA-NITRIX CO., LTD.; PACIFIC METALS CO., LTD. Owner name: MITSUBISHI CHEMICAL CORPORATION Free format text: FORMER NAME(S): DIA-NITRIX CO., LTD.; PACIFIC METALS CO., LTD. |
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| PC | Assignment registered |
Owner name: PACIFIC METALS CO., LTD. Free format text: FORMER OWNER(S): MITSUBISHI CHEMICAL CORPORATION; PACIFIC METALS CO., LTD. |