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EP0814907A1 - Sorbant polymere pour procede de recuperation d'ions - Google Patents

Sorbant polymere pour procede de recuperation d'ions

Info

Publication number
EP0814907A1
EP0814907A1 EP96904667A EP96904667A EP0814907A1 EP 0814907 A1 EP0814907 A1 EP 0814907A1 EP 96904667 A EP96904667 A EP 96904667A EP 96904667 A EP96904667 A EP 96904667A EP 0814907 A1 EP0814907 A1 EP 0814907A1
Authority
EP
European Patent Office
Prior art keywords
polymeric foam
foam
cells per
coarse
open cell
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.)
Withdrawn
Application number
EP96904667A
Other languages
German (de)
English (en)
Other versions
EP0814907A4 (fr
Inventor
William Harold Jay
Paul Leslie Breuer
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.)
Linfox Technology Pty Ltd
Montech Pty Ltd
Original Assignee
Linfox Technology Pty Ltd
Montech Pty Ltd
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 Linfox Technology Pty Ltd, Montech Pty Ltd filed Critical Linfox Technology Pty Ltd
Publication of EP0814907A1 publication Critical patent/EP0814907A1/fr
Publication of EP0814907A4 publication Critical patent/EP0814907A4/fr
Withdrawn legal-status Critical Current

Links

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
    • 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
    • C22B3/42—Treatment or purification of solutions, e.g. obtained by leaching by ion-exchange extraction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J39/00—Cation exchange; Use of material as cation exchangers; Treatment of material for improving the cation exchange properties
    • B01J39/08—Use of material as cation exchangers; Treatment of material for improving the cation exchange properties
    • B01J39/16—Organic material
    • B01J39/18—Macromolecular compounds
    • B01J39/19—Macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J41/00—Anion exchange; Use of material as anion exchangers; Treatment of material for improving the anion exchange properties
    • B01J41/08—Use of material as anion exchangers; Treatment of material for improving the anion exchange properties
    • B01J41/12—Macromolecular compounds
    • B01J41/13—Macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds
    • 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 a process for the removal of ions from slurries, pulps or other dispersions of solids in liquids.
  • the present invention relates to a process for the selective removal of ions from dispersion of solids in solutions and . also relates to coarse open cell polymeric foams which support ion exchange sites.
  • ions are removed from solutions by the use of processes such as ion exchange onto solid beads or fibres, membrane processes, activated carbon adsorption, precipitation, solvent extraction, ion flotation and the like.
  • processes such as ion exchange onto solid beads or fibres, membrane processes, activated carbon adsorption, precipitation, solvent extraction, ion flotation and the like.
  • the removal of ions from solutions which also contain solid materials dispersed throughout such as in slurries, pulps and the like is more difficult.
  • the application of ion exchange resins and activated carbon is widely practiced throughout many industries including the minerals processing industry where selective removal of ions from slurries is necessary and has become the method of choice in the recovery of gold by cyanidation and in the recovery of uranium as the uranyl sulphate, for example.
  • the density of the solid sorbents desirably matches or at least approximates the pulp density which is only determined by the ratio of mass of the solid particles to the solution.
  • the density of the solid particles cannot be modified, nor is it generally possible to significantly change the density of the solution.
  • Extractive metallurgical techniques generally seek to obtain metal values from ores or concentrates.
  • the solids may be introduced into a reactor together with requisite lixiviants to dissolve the metal values and in doing so, typically produces a slurry.
  • other ions may also be brought into solution.
  • a material which can selectively remove or recover the desired ion is added to the slurry usually in the form of a solid sorbent dispersed in the slurry.
  • the solution containing the dissolved ions is separated from the solid materials and the metal ions are then recovered or removed from the clarified solution.
  • the solid sorbent is typically recovered from the slurry or from the solution by screening.
  • the particle size of the resin is selected in a size range which is generally fine enough to exhibit desirable loading and elution kinetics. Fine ion exchange beads are more difficult to recover from these pulps because the screen opening size employed must be greater than the particles making up the slurry, but smaller than that of the smallest ion exchange beads.
  • the ion exchange resin bead size is preferentially recommended to be between 6 and 12 mesh. 'Blinding", or screen blocking can thus readily occur.
  • ion exchange resin beads suffer from the problem of osmotic shock. Thus, swelling and shrinkage of the ion exchange resin bead during loading and stripping of the metal ions contained thereon can lead to resin breakage.
  • solutions containing solid materials dispersed therein may be passed through coarse open cell polymeric foams having ion exchange sites incorporated into the open cell polymeric foam and the selective removal of ions from solution may be achieved. Accordingly, there is provided a process for the selective removal of ions from a solution having solid materials dispersed therein comprising passing the solution having solid materials dispersed therein through a bed of coarse open cell polymeric foam having ion exchange sites.
  • Suitable coarse open cell polymeric foams include coarse cell polyurethanes and preferably coarse cell reticulated polyurethanes.
  • Polyurethane-based polymers are recognised for their high abrasion resistance.
  • These polyurethane-based polymers have also been modified to incorporate ion exchanging sites as described in PCT/AU93/00312 and PCT/AU94/00793 incorporated herein by reference and also include any polymeric resin which has been provided with a suitable functionality for the sorption of the desired ion either by interpenetration by a second polymer (such second polymer typically as described in South African Patent ZA 89/2733 and Canad.
  • Patent Application 2,005,259) with or without further chemical modification, polyurethane polymer chemical modification, organic extractant impregnation such as described by Lin et al in U.S. Patents 4,814,007, 4,895,597, 4,992,200, 5,028,259, U.K. Patent G.B.2,186,563A and PCT W093/ 19212 and Virnig in U.S. Patents 5,198,021 and 5,340,380 or known to those skilled in the application of liquid ion exchange extractants, etc.
  • These polyurethane-based polymers can be produced in a variety of forms such as beads or fibres, but can also be expanded to produce flexible, semiflexible and rigid foams. Blocks of foams several cubic metres in size may be produced.
  • blocks of foam can be produced by well established bonding processes. These blocks of foam can be cut to any suitable shape and size dependent upon the requisite application. Alternatively, blocks of foam can be produced to the desired size and shape by pouring the liquid foaming reagents into a suitable mould and after the reaction has reached a suitable degree of curing, removing the item from the mould.
  • the polyurethane foams are preferably flexible and can either be polyester- based or polyether-based.
  • Polyether-based polyurethane foams are generally preferred because of their demonstrated improved chemical resistance over the ester foams. However, for some specific applications ester foams may possess suitable properties.
  • the polyether-based foams may be produced by the reaction under controlled conditions of a suitable polyol or blend of polyols with one or more diisocyanates in the presence of catalysts, cell control agents and, if required, fillers, flame retardants, etc.
  • the polyols are usually based upon the reaction of di- or higher functional materials with ethylene oxide (EO), propylene oxide (PO), or mixtures of these two oxides.
  • glycerine is one preferred starting material and this is reacted with EO and/or PO to produce a polyol with a molecular weight generally in the range of 3000 to 6000.
  • the diisocyanate is generally toluene diisocyanate (TDI) or diphenylmethane-4,4'- diisocyanate-based materials (MDI), but is not limited to these two isocyanates.
  • Polyurethane foams may be "reticulated", that is, most or all of the residual “windows" or cell walls are removed by such processes as have been described by
  • these reticulated polymeric polyurethane foams are able to have solutions comprising solid materials, such as pulps or slurries similar in composition to those found in the minerals processing industry very rapidly pumped through them without any indication of blocking. Fine-celled flexible polyurethane foams under the same conditions are rapidly blocked by the solid materials thus preventing the slurry from continuing to flow freely through the polyurethane foam.
  • the selection of cell size in the polymeric foam is dependent on the largest particle size of the solid materials contained in the solution. It is preferred that the cell size be at least three times the largest particle size of solid materials in the solution.
  • the polymeric foam has a cell size in the range of from 45 cells per linear inch (180 cells per 100mm) to less than 15 cells per linear inch (60 cells per 100mm). It is desirable to select a cell size wherein the surface area of the polymeric foam is maximized without resulting in blocking of the foam with the solid particles from the solution.
  • Beds of coarse open cell polymeric foams containing the desired ligands may be housed in suitably constructed vessels. Such vessels may be designed to allow liquid containing solid materials to pass through the polymeric foam either by gravity or by pumping or by other means and provides an improved recovery system for the desired ions. Solutions containing from less than 15% of solids to over 50% by weight of solids and varying in particle size from less than 45 micron to greater than 150 micron have been continuously pumped or passed through coarse open cell polymeric foams.
  • the polymeric foam may be able to undergo repeated flexing and therefore the additional possibility of applying a mechanical pulsing action to the foam bed is achieved.
  • the polymeric foam comprises ion exchange sites. These sites may be provided in the initial manufacturing process of the polymeric foam or may be provided by modification of the foam after its initial manufacture. The selection of appropriate functional groups at the ion exchange sites allows the selective recovery of a broad range of ions in solution.
  • the polymeric foam may have ion exchange functionality for the selective removal of heavy metals including arsenic, cadmium, chromium, iron, zinc and mercury; precious met.als including gold, silver, platinum, palladium, rhodium, iridium, ruthenium and osmium; other anions and cations including halides, sulfates, nitrates, cyanides, thiocyanates, cyanogen, carbonates and phosphates.
  • heavy metals including arsenic, cadmium, chromium, iron, zinc and mercury
  • precious met.als including gold, silver, platinum, palladium, rhodium, iridium, ruthenium and osmium
  • other anions and cations including halides, sulfates, nitrates, cyanides, thiocyanates, cyanogen, carbonates and phosphates.
  • oxygen may be required as part of the chemical reaction, for example in the dissolution of gold in oxygenated alkaline sodium cyanide solution.
  • These coarse and open cell polymeric foams will allow the passage of both the solution, slurry and if required, air, oxygen or other gas.
  • the polymer foam in some cases may also assist by improving the distribution of the gas throughout the solution, pulp or slurry.
  • the present invention provides an ion-selective coarse open cell polymeric foam as hereinabove described in which the cell size is sufficient to allow solutions having solids dispersed therein to pass through said foam.
  • preg robbing In the gold industry, the loss of gold cyanide by adsorption of the aurocyanide anion onto the surfaces of clays, sulphide minerals, carbonaceous materials, etc. is well recognised and has been termed "preg robbing".
  • diluting the pulps to low solids content such as 15% solids content and lower, can also reduce “preg robbing" and thus increase metal ion recovery.
  • the described fixed-bed of ligand-modified reticulated polyurethane foam provides a short path length for the metal ions to travel prior to sorption. Additionally, these modified polymers do not catalyse the oxidation of the sodium cyanide to cyanates or cyanogen as is the case for activated carbon.
  • the slurry pumped to tailings normally contains cyanide, as "free" cyanide or WAD (weak acid dissociable) cyanide, thiocyanates, etc.
  • WAD weak acid dissociable cyanide
  • the tailings pondage contains anions which are toxic to human, animal and bird life and therefore represent a significant environmental hazard. The presence of these toxic anions may well prevent the return of these sands underground as mine fill because of the potential for the toxic ions to enter the water table.
  • the application of a fixed bed of a suitable reticulated polyurethane foam for cyanide recovery offers a number of economic and kinetic advantages as will be described.
  • the free cyanide is converted to a WAD cyanide such as by the treatment of the slurry with a metal or soluble metal salt in particular with copper or zinc sulphate.
  • the slurry then passes through a suitable bed of a selected reticulated polyurethane foam which has been modified to contain a suitable ligand.
  • the complex metal cyanide ion is rapidly adsorbed onto the polyurethane foam and the cyanide-depleted slurry passes to the tailings dam without the need for any pH adjustment (other than that which may be required by any particular mining or environmental government regulation applicable to that mine).
  • the loaded polyurethane foam column is acidified to generate HCN gas which is adsorbed in an alkaline solution.
  • a suitable courier gas such as nitrogen or air may be required.
  • the acid solution may be reused for further stripping.
  • a closed circuit plant can be designed in which much smaller volumes of air and solutions are required.
  • the WAD cyanide can be stripped from the column.
  • HCN gas can be generated from the strip solution and sodium cyanide formed or alternatively sodium cyanide reformed by electrolysis in a suitably designed electrolysis cell.
  • a further application for the technology would be for the removal of soluble salts in lignite and other coals or for the removal of dissolved metal salts from soils in soil remediation processes, again, by allowing the slurry containing die metal ions to flow through a fixed bed of reticulated polyurethane foam having ion exchange sites to sorb the metal ions.
  • a slurry was prepared by distributing 40 parts by weight of ground quartz particles in 100 parts of water. 80% of the quartz particles were between 100 micron and 150 micron in size, the remainder lay between 45 micron and 100 micron in size. This slurry was pumped both downwards and also upwards through a 1.2 metre high block of reticulated polyurethane foam at particle flow rates in excess of 1 cm per second with negligible pressure drop across the bed.
  • a slurry was prepared by distributing 40 parts by weight of a clay mineral in 100 parts of water. 80% of the clay particles passed through a 75 micron sieve. The slurry was pumped upwards through a 1.2 metre high block of reticulated polyurethane foam at particle flow rates of up to 1 cm per second. Air was introduced into the base of the foam bed and rapidly travelled through it in a vertical direction witiiout substantial pressure drop.
  • Brown coal was mixed witii water in a high shear mixer to disperse the fibrous coal particles and to form a slurry containing 30% solids. This slurry was pumped upwards through a 1.2 metre high block of reticulated polyurethane foam containing about 15 cells per linear inch (i.e., 60 cells per 100 mm) at particle flow rates of up to 1 cm per second.
  • the resultant interpenetrated resin was then further reacted by soaking for 12 hours at 55°C in a mixture of 1:5 by volume of pyridine:acetone.
  • the foam treated as described above then was placed in a column and a gold cyanide solution containing 40 percent of quartz to form a slurry was pumped upwards through it. A loading of 41,500 mg Au/kg foam onto this modified polymer was obtained.
  • the quartz particles slurry containing the gold cyanide had the following particle size:
  • a gold-containing ore (head grade 4.5 ppm) and consisting of quartz (29%), stilpromalane (14%), chlorite (30%), calcite (5%), muscovite (4%), dolomite (3%), pyrrhotite (10%), pyrite (2%) and minor miner s to 100% was ground to give a Pgo of 75 micron at a pulp density of 56% and treated with sodium cyanide in a conventional carbon-in-leach plant using a direct injection of oxygen. .An analysis of the tailings water showed that it contained 104 ppm of free and WAD cyanide and 360 ppm thiocyanate.
  • the tailings from this gold recovery circuit were passed over a 150 micron vibrated DSM screen to remove any oversize material and then allowed to flow under gravity through a column 30 cm diameter and two metres high containing a 60 cell per 100 mm reticulated polyurethane foam of density 28 kg/m 3 . No abrasion was observed after 21 days continual slurry flow.
  • the interpenetrated polyurethane foam was cured by heating under nitrogen for 18 hours at 80 "C in a sealed vessel and then for a further period of 18 hours at 80 °C in air. The polymer was then immersed for 12 hours at 50 " C in a solution containing pyridine 20 and acetone 100.
  • Example 2 An acid mine drainage slurry from a copper mine and containing 9.1% quartz and 11 ppm of soluble copper was passed through the column described in Example 2.
  • the column contained a 60 cell per 100mm reticulated polyurethane foam which had been impregnated with di[2-ethylhexyl] phosphoric acid [D2EHPA]. After 1.5 minute contact time, 53% of the copper was removed from the slurry.
  • a slurry with a maximum particle size of 180 micron and containing 11.9 ppm gold, 11.0 ppm copper, 13.2 ppm zinc, and 14.0 ppm ferric iron all as cyanides, and 0.3 g/1 free cyanide at pH 11.0 was passed through the column as described in Example 2 at a flow rate of 90 ml /minute.
  • the column was packed with a 15 cell/inch (60 cells/ 100 mm) reticulated polyurethane foam which had been impregnated with a gold-selective organic extractant (Aliquat 336 manufactured by Henkel Corp.).
  • a slurry containing 10% of solid matter wid an average particle size of 100 micron and containing 5.92 ppm of chromium( VI) at pH 2.2 was passed through the column as described in Example 2 with a flow rate of 90 ml/minute.
  • the column was packed with a reticulated and open-celled flexible polyurethane foam (60 cells per 100 mm) which had been chemically modified to contain approximately 35% of a pyridine-based interpenetrated polymer.
  • the chemical modification was conducted by interpenetrating under nitrogen the reticulated polyurethane foam with a solution containing 100 parts vinylbenzyl chloride, 68 parts styrene, 7.5 parts divinyl benzene, 0.75 parts azobisisobutyronitrile (AIBN) and 3.7 parts toluene.
  • the interpenetrated polyurethane foam was cured by heating under nitrogen for 18 hours at 80°C in a sealed vessel and then for a further period of 18 hours at 80°C in air.
  • the polymer was then immersed for 12 hours at 50°C in a solution containing pyridine 20 and acetone 100. After a minute contact time 79% of the chromium (VI) was removed.
  • the column once fully loaded wid chromium (VI), 91% of the chromium was stripped using seven bed volumes of a solution containing 0.5 molar sodium sulphate and 0.1 molar sodium hydroxide.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Water Treatment By Sorption (AREA)
  • Treatment Of Liquids With Adsorbents In General (AREA)

Abstract

Procédé permettant la récupération sélective d'ions à partir de dispersions de solides dans des solutions, et qui concerne en outre des mousses polymères à cellules ouvertes grossières avec des sites d'échange d'ions de support. Ledit procédé de récupération sélective d'ions d'une solution dans laquelle sont dispersés des matériaux solides consiste à faire passer ladite solution à travers un lit de mousse polymère à cellules ouvertes grossières dotée de sites d'échange d'ions. Ladite mousse permettant la sélection d'ions présente une taille de cellules suffisante pour permettre à des solutions contenant des solides en dispersion de passer à travers ladite mousse.
EP96904667A 1995-03-10 1996-03-12 Sorbant polymere pour procede de recuperation d'ions Withdrawn EP0814907A4 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
AUPN4830/95 1995-03-10
AUPN483095 1995-03-10
PCT/AU1996/000133 WO1996028251A1 (fr) 1995-03-10 1996-03-12 Sorbant polymere pour procede de recuperation d'ions

Publications (2)

Publication Number Publication Date
EP0814907A1 true EP0814907A1 (fr) 1998-01-07
EP0814907A4 EP0814907A4 (fr) 1999-05-19

Family

ID=3789161

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96904667A Withdrawn EP0814907A4 (fr) 1995-03-10 1996-03-12 Sorbant polymere pour procede de recuperation d'ions

Country Status (5)

Country Link
EP (1) EP0814907A4 (fr)
CA (1) CA2217866A1 (fr)
NZ (1) NZ302613A (fr)
WO (1) WO1996028251A1 (fr)
ZA (1) ZA961914B (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPO900097A0 (en) * 1997-09-05 1997-10-02 Arton (No 001) Pty Ltd Process
AU749790B2 (en) * 1997-09-25 2002-07-04 Oretek Ltd Ion exchange
AUPO946297A0 (en) 1997-09-25 1997-10-16 Holbray Pty Ltd Ion exchange
WO2004078342A1 (fr) 2003-03-04 2004-09-16 Manac Inc. Entraineur pour substance presentant un substituant anionique
WO2016202767A1 (fr) * 2015-06-19 2016-12-22 Basf Se Composite à base de polyuréthane pour la neutralisation d'un drainage minier acide (amd)
GB202010885D0 (en) 2020-07-15 2020-08-26 Johnson Matthey Plc Methods for the separation and/or purification of metals

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2820732A1 (de) * 1978-05-12 1979-11-22 Basf Ag Chelatbildner und/oder chelatkomplexe enthaltende offenzellige polyurethanschaumstoffe
FR2488264A1 (fr) * 1980-08-05 1982-02-12 Le I Textilnoi Materiau poreux a cellules ouvertes, charge et reactif
CA2138760A1 (fr) * 1992-06-25 1994-01-06 Frank Lawson Resine echangeuse d'ions
AU629790B3 (en) * 1992-06-29 1992-10-08 William Harold Jay An electrochemical process employing a modified polymeric foam to enhance the recoverability of metal values from solution

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
No further relevant documents disclosed *
See also references of WO9628251A1 *

Also Published As

Publication number Publication date
CA2217866A1 (fr) 1996-09-19
WO1996028251A1 (fr) 1996-09-19
EP0814907A4 (fr) 1999-05-19
NZ302613A (en) 2000-01-28
ZA961914B (en) 1996-09-12

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