SULFONATED MODIFIERS FOR FROTH FLOTATION

Abstract

Improved sparge compositions for reverse froth flotation separation and uses thereof, and methods of reverse froth flotation are described. The sparge compositions comprise sulfonated polymeric modifiers which can act as dispersants and depressants, and the compositions are suitably used in the reverse froth flotation of particulate material containing ultrafine particles. For example, the compositions and methods can be used in the separation of iron oxide beneficiary from iron ores comprising silica, silicates, and the like.

Claims

1. A sparge composition comprising: (i) a medium; (ii) an ore selected from potash ore, coal, metal oxide ore, limestone, clay, sand, gravel, diatomite, kaolin, bentonite, silica, barite, gypsum, talc, zircon, fluorite, and any combination thereof, the ore comprising a gangue and a beneficiary; (iii) a collector; and (iv) a modifier comprising one or more sulfonated polymers, wherein at least one of the one or more sulfonated polymers (a) has a weight average molecular weight of from about 300 g/mole to about 100,000 g/mole, (b) comprises a residue of sulfonated vinyl alcohol, sulfonated acrylamide, sulfomethylated acrylamide, 2-acrylamido-2-methylpropane sulfonate, styrene sulfonate, or any combination thereof, and (c) further comprises a residue of acrylic acid, methacrylic acid, acrylamide, vinyl alcohol, maleic acid, a maleic acid ester, or any combination thereof.

2. The sparge composition of claim 1, wherein the ore is a metal oxide ore.

3. The sparge composition of claim 1, wherein the beneficiary comprises an iron oxide.

4. The sparge composition of claim 1, wherein the collector is an amine.

5. The sparge composition of claim 1, wherein the gangue comprises silicate, silica, carbonate, or a combination thereof.

6. The sparge composition of claim 1, wherein the modifier further comprises a sulfonated lignin, a sulfonated starch, a sulfonated cellulose, a sulfonated guar gum, a sulfonated xanthan gum, or any combination thereof.

7. The sparge composition of claim 1, wherein the beneficiary comprises magnetite.

8. The sparge composition of claim 1, wherein the one or more sulfonated polymers comprises a copolymer of acrylic acid and a sulfomethylated acrylamide.

9. The sparge composition of claim 1, wherein the collector is a C12-C24 fatty amine, a C12-C24 fatty diamine, a C6-C13 ether amine, a C6-C13 ether diamine, or any combination thereof.

10. The sparge composition of claim 1, wherein the collector comprises C13 ether diamine.

11. A method of froth flotation comprising: forming a sparge composition, the sparge composition comprising (i) a medium, (ii) an ore selected from potash ore, coal, metal oxide ore, limestone, clay, sand, gravel, diatomite, kaolin, bentonite, silica, barite, gypsum, talc, zircon, fluorite, and any combination thereof, the ore comprising a gangue and a beneficiary, (iii) a collector, and (iv) a modifier comprising one or more sulfonated polymers, wherein at least one of the one or more sulfonated polymers (a) has a weight average molecular weight of from about 300 g/mole to about 100,000 g/mole, (b) comprises a residue of sulfonated vinyl alcohol, sulfonated acrylamide, sulfomethylated acrylamide, 2-acrylamido-2-methylpropane sulfonate, styrene sulfonate, or any combination thereof, and (c) further comprises a residue of acrylic acid, methacrylic acid, acrylamide, vinyl alcohol, maleic acid, a maleic acid ester, or any combination thereof; and sparging the sparge composition to yield a sparged composition, the sparged composition comprising a froth and a sparged slurry.

12. The method of claim 11, wherein the beneficiary comprises a metal oxide.

13. The method of claim 11, wherein the beneficiary comprises an iron oxide.

14. The method of claim 11, wherein the collector is an amine.

15. The method of claim 11, wherein the gangue comprises silicate, silica, carbonate, or any combination thereof.

16. The method of claim 11, wherein the modifier further comprises a sulfonated lignin, a sulfonated starch, a sulfonated cellulose, or any combination thereof.

17. The method of claim 11, wherein the beneficiary comprises magnetite.

18. The method of claim 11, wherein the one or more sulfonated polymers comprises a copolymer of acrylic acid and sulfomethylated acrylamide.

19. The method of claim 11, wherein the amine collector is a C12-C24 fatty amine, a C12-C24 fatty diamine, a C6-C13 ether amine, a C6-C13 ether diamine, or any combination thereof.

20. The method of claim 11, wherein the modifier is employed in a grinding process, a desliming process, a conditioning process, or any combination thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 shows a plot of the percentage grade of iron recovered versus % silica removal for three froth flotation tests.

DETAILED DESCRIPTION

[0025] Although the present disclosure provides references to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims.

Definitions

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present document, including definitions, will control.

[0027] As used herein, the terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional acts or structures. The singular forms “a,” “and” and “the” include plural references unless the context clearly dictates otherwise. The present disclosure also contemplates other embodiments “comprising,” “consisting of” and “consisting essentially of,” the embodiments or elements presented herein, whether explicitly set forth or not.

[0028] As used herein, the term “optional” or “optionally” means that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances in which it does not.

[0029] As used herein, the term “about” modifying, for example, the quantity of an ingredient in a composition, concentration, volume, process temperature, process time, yield, flow rate, pressure, and like values, and ranges thereof, employed in describing the embodiments of the disclosure, refers to variation in the numerical quantity that can occur, for example, through typical measuring and handling procedures used for making compounds, compositions, concentrates or use formulations; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of starting materials or ingredients used to carry out the methods, and like proximate considerations. The term “about” also encompasses amounts that differ due to aging of a formulation with a particular initial concentration or mixture, and amounts that differ due to mixing or processing a formulation with a particular initial concentration or mixture. Where modified by the term “about” the claims appended hereto include equivalents to these quantities. Further, where “about” is employed to describe a range of values, for example “about 1 to 5” or “about 1 to about 5”, the recitation means “1 to 5” and “about 1 to about 5” and “1 to about 5” and “about 1 to 5” unless specifically limited by context.

[0030] As used herein, “ore” means any solid terranean material of economic value that is obtained by excavation such as quarrying, open-cast mining, or pit mining: “ore” is construed herein to include not only rock, minerals, and mineral aggregates containing one or more metals in elemental and/or chemically compounded forms, but also coal and other solid terranean substances.

[0031] As used herein, “carbonate”, unless specified to the contrary, means inorganic carbonate such as material containing CO.sub.3.sup.2−, HCO.sub.3.sup.− ions and counterions.

[0032] As used herein, “phosphate”, unless specified to the contrary, refers to inorganic phosphate such as material containing PO.sub.4.sup.3−, H.sub.2PO.sub.4.sup.2−, and H.sub.2PO.sub.4.sup.− ions and counterions.

[0033] As used herein, “medium” means a material that is liquid at 20° C. and 1 atmosphere pressure. In any of the embodiments herein, the medium can comprise, consist of, or consist essentially of water.

[0034] As used herein, a “collector” means a material that selectively adheres to targeted particles in a sparge composition, and increases adhesion or association of the targeted particles to bubbles of a gas during sparging. “Targeted particles” are gangue-rich particles (in reverse froth flotation) or beneficiary-rich particles (in direct froth flotation).

[0035] As used herein, “amine collector” means an organic moiety comprising an amine group and/or an ammonium group. Non-limiting examples of amine collectors include C12-C24 fatty amines, C12-C24 fatty diamines, C6-C13 ether amines, C6-C13 ether diamines, or any combination thereof, further wherein the term “amine” refers to the free amine, the conjugate acid thereof, or a combination thereof.

[0036] As used herein, “particulate” or “particulate material” means a plurality of particles.

[0037] As used herein, “particle” means a discreet, solid object to which can be ascribed physicochemical properties such as volume or mass, wherein a particle has a largest maximum dimension in any direction of about 0.001 μm to about 5 mm.

[0038] As used herein, “ultrafine particles” or “ultrafines” means a particulate having a particle size of less than 10 μm as measured by throw-action sieve analysis carried out wet. The procedure for sieve analysis is outlined in American Society for Testing and Materials (ASTM) C 136[2].

[0039] As used herein, “comminute” means to reduce the particle size of a particulate. In embodiments, comminuted means powdered, pulverized, ground, or otherwise divided by mechanical means.

[0040] As used herein, “sparge composition” means a composition comprising a particulate material, a collector, and a liquid medium. Such a composition has a liquid surface and comprises a slurry of the particulate material in the medium. Such a composition, after being sparged, comprises froth at the liquid surface and a sparged slurry. In direct froth flotation, the froth comprises a concentrate, and the sparged slurry comprises tailings. In reverse froth flotation, the froth comprises tailings and the sparged slurry comprises a concentrate.

[0041] As used herein, “sparge”, “sparged”, or “sparging” refers to the introduction of a gas into a sparge composition for the purpose of creating a plurality of bubbles that migrate upwards within the liquid. In embodiments, the gas is air.

[0042] As used herein, “concentrate” refers to a material in which a beneficiary has been concentrated by a froth flotation process. The concentrate has a higher concentration of the beneficiary (as a ratio by weight of beneficiary to beneficiary plus gangue) than the particulate material of the sparge composition before sparging.

[0043] As used herein, “tailings” refers to a material in which a gangue has been concentrated by a froth flotation process. The tailings have a higher concentration of the gangue (as a ratio by weight of gangue to beneficiary plus gangue) than the particulate material of the sparge composition before sparging.

[0044] As used herein, “sparged slurry” means the liquid body of a sparge composition that has been sparged, wherein a froth has formed at the air-liquid interface. As used herein, the sparged slurry excludes or substantially excludes the froth.

[0045] As used herein “slurry of particles” means a composition comprising a liquid medium and particulate material, wherein the particulate material is dispersed and/or suspended in the medium, and wherein the composition excludes or substantially excludes a collector. In embodiments, the liquid medium consists essentially of water.

[0046] As used herein, a “depressant” means a material that selectively reduces the adhesion or association of untargeted particles in a sparge composition to bubbles of a gas during sparging. Untargeted particles are gangue-rich particles in direct froth flotation or beneficiary-rich particles in a reverse froth flotation. A depressant acts to decrease the migration of untargeted particles to the surface of a sparged composition.

[0047] As used herein, a “frother” or “frothing agent” means a composition of matter that reduces the surface tension of water and enables the formation of a froth at air-liquid interface of a sparge composition during sparging.

[0048] As used herein, “dispersant” means a material that facilitates dispersion of particles of an ore in a liquid medium, assists in the dispersion of particles of an ore in a liquid medium, stabilizes a dispersion of particles of an ore in a liquid medium, or any combination thereof. In embodiments, a dispersant is a material that disperses ultrafine particles of the ore in a medium.

[0049] As used herein, a “modifier” means a material that is, acts as, or is effective as a dispersant, a depressant, or both a dispersant and depressant. In embodiments, the modifiers of the invention are, act as, or are effective as both dispersants and depressants.

[0050] As used herein, “ATBS” means 2-acrylamido-2-methylpropane sulfonic acid and/or salts thereof, except where otherwise specified as follows: as used herein, “ATBS sulfonic acid” means 2-acrylamido-2-methylpropane sulfonic acid; as used herein an “ATBS salt” means a salt of 2-acrylamido-2-methylpropane sulfonic acid.

[0051] As used herein, “flotation” of a material refers to a process in froth flotation in which during the sparging of a slurry of a comminuted ore in a liquid medium, the material migrates at least partially into a froth layer that forms at the liquid-air interface.

[0052] As used herein, “depression” of a material refers to a process in froth flotation in which during the sparging of a slurry of a comminuted ore in a liquid medium, the material remains substantially within the sparged slurry and does not tend to migrate into the froth layer.

[0053] As used herein, “sulfonated monomer” means a polymerizable compound comprising at least one sulfonate or sulfate group (—SO.sub.3H, —SO.sub.3R, —SO.sub.3.sup.−, —O—SO.sub.3H, —O—SO.sub.3R, or —O—SO.sub.3.sup.−, where R is alkyl, aryl, alkaryl, or another organic group).

[0054] As used herein, “sulfonated monomer residue” and like terms mean a polymerized residue of a monomer, wherein the residue comprises at least one sulfonate or sulfate moiety.

[0055] As used herein, “sulfonate moiety”, “sulfonate”, “sulfonate group”, “sulfonated” and like terms means a moiety comprising at least one sulfonate or sulfate group (—SO.sub.3H, —SO.sub.3R, —SO.sub.3.sup.−, —O—SO.sub.3H, —O—SO.sub.3R, or —O—SO.sub.3.sup.−, where R is alkyl, aryl, alkaryl, or another organic group).

[0056] As used herein, “sulfonated polymer” means a polymer comprising at least one sulfonate or sulfate group (—SO.sub.3H, —SO.sub.3R, —SO.sub.3.sup.−, —O—SO.sub.3H, —O—SO.sub.3R, or —O—SO.sub.3.sup.−, where R is alkyl, aryl, alkaryl, or another organic group).

[0057] As used herein, “metal oxide ore” means an ore in the form of a particulate comprising metal ions and oxide ions. Non-limiting examples of metal oxide ores include comminuted magnetite, hematite, goethite, and limonite.

[0058] As used herein, “iron ore” refers to those ores comprising iron ions. Examples include but are not limited to those comprising magnetite, hematite, goethite, limonite, or any combination thereof.

DISCUSSION

[0059] Preferred methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in practice or testing of the present invention. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting.

[0060] Applicants have found that sulfonated polymers having a weight average molecular weight of about 100,000 g/mole or less unexpectedly improve the floating of gangue minerals in the reverse flotation of metal oxide ores, and have found that sulfonated polymers act as dispersants for both beneficiary and gangue particles for metal oxide ores. Therefore, sulfonated polymers can be used as dispersants in both direct and reverse froth flotation and can be applied before flotation in a grinding process, a desliming process, a conditioning process, or any combination thereof. In embodiments, the sulfonated polymers decrease slime coating in the froth flotation.

[0061] The polymers comprise one or more sulfonate and/or sulfate groups. Disclosed are methods and compositions for froth flotation that include modifiers that comprise, consist of, or consist essentially of one or more sulfonated polymers. The modifiers, compositions comprising the modifiers, and methods can be implemented in existing froth flotation installations for separation of beneficiary and gangue of a comminuted ore. The comminuted ore comprises particles of ore. In embodiments, the particles of ore comprise, consist of, or consist essentially of ultrafine particles. Used in a reverse froth flotation process in a medium for the separation of beneficiary and gangue from a metal oxide ore, the modifiers of Applicant's invention unexpectedly provide improved separation and selectivity toward concentrate or tailings, improved recovery of beneficiary (as measured by weight of beneficiary recovered as a proportion of total beneficiary in the metal oxide ore), higher grade (as measured by weight of beneficiary in the concentrate), improved depressing action of depressant on the beneficiary (as measured by reduction of depressant dosage), improved dispersion of particles of ore, improved dispersion of ultrafines of ore, reduced slime coating of particles of ore, or any combination thereof.

First Embodiments

[0062] Therefore, in first embodiments, there is provided a sparge composition for froth flotation, the sparge composition comprising, consisting of, or consisting essentially of a medium, an ore comprising a beneficiary and a gangue, a collector, and a modifier comprising one or more sulfonated polymers. In embodiments, the sparge composition for froth flotation is a sparge composition for reverse froth flotation. In embodiments, the medium comprises, consists of, or consists essentially of water. In embodiments, the medium is water. In embodiments, the ore is selected from potash ore, coal, metal oxide ore, limestone, clay, sand, gravel, diatomite, kaolin, bentonite, silica, barite, gypsum, talc, zircon, fluorite, and any combination thereof. In embodiments, the ore comprises, consists of, or consists essentially of a metal oxide ore. In embodiments, the ore comprises, consists of, or consists essentially of an iron ore. In embodiments, the metal oxide ore is an iron ore. In embodiments, the beneficiary comprises, consists of, or consists essentially of an iron oxide. In some such embodiments, the beneficiary comprises, consists of, or consists essentially of magnetite, hematite, goethite, limonite, or any combination thereof. In embodiments, the beneficiary comprises, consists of, or consists essentially of magnetite. In embodiments, the gangue comprises, consists of, or consists essentially of a silicate, silica, carbonate, or a combination thereof.

[0063] In alternative first embodiments, the metal oxide ore is selected from iron ore, wolframite-scheelite, copper oxide ore, zinc oxide ore, lead oxide ore, oxide ore comprising gold, bauxite, and any combination thereof.

[0064] In first embodiments, the amine collector is selected from C12-C24 fatty amines, C12-C24 fatty diamines, C6-C13 ether amines, C6-C13 ether diamines, or any combination thereof.

[0065] In first embodiments, the amine collector is selected from one or more fatty amines having the structure (I)

R.sub.6NH.sub.2,   (I)

wherein R.sub.6 is C12-C24 linear or branched alkyl; one or more fatty diamines having the structure (II)

R.sub.6—NH—R.sub.7—NH.sub.2  (II),

wherein R.sub.6 is C12-C24 linear or branched alkyl and R.sub.7 is a linear or branched hydrocarbon chain, in some embodiments (CH.sub.2).sub.3; one or more ether amines having the structure (III)

R.sub.8—O—R.sub.7—NH.sub.2  (III),

wherein R.sub.8 is C6-C13 branched or linear alkyl and R.sub.7 is a linear or branched hydrocarbon chain, in embodiments (CH.sub.2).sub.3; one or more ether diamines having the structure (IV)

R.sub.9—O—R.sub.7—NH—R.sub.7—NH.sub.2  (IV),

wherein R.sub.9 is C8-C13 branched or linear alkyl and R.sub.7 is a linear or branched hydrocarbon chain, in embodiments (CH.sub.2).sub.3.

[0066] In first embodiments, the amine collector comprises, consists of, or consists essentially of the C13 ether diamine having the structure (V)

H.sub.2N—(CH.sub.2).sub.3—NH—(CH.sub.2).sub.3—O—(CH.sub.2).sub.10—CH(CH.sub.3).sub.2  (V).

[0067] In first embodiments, the one or more sulfonated polymers is selected from a sulfonated natural polymer, a sulfonated synthetic polymer, and a combination thereof.

[0068] In first embodiments the weight average molecular weight of the one or more sulfonated synthetic polymers is from about 300 to about 5,000,000, in embodiments about 300 to about 1,000,000, in embodiments about 300 to about 500,000, in embodiments about 300 to about 100,000, in embodiments about 300 to about 50,000, in embodiments about 300 to about 35,000, in embodiments about 300 to about 30,000, in embodiments about 300 to about 25,000, in embodiments from about 500 to about 5,000,000, in embodiments about 500 to about 1,000,000, in embodiments about 500 to about 500,000, in embodiments about 500 to about 100,000, in embodiments about 500 to about 50,000, in embodiments about 500 to about 25,000, in embodiments from about 700 to about 5,000,000, in embodiments about 700 to about 1,000,000, in embodiments about 700 to about 500,000, in embodiments about 700 to about 100,000, in embodiments about 700 to about 50,000, in embodiments about 700 to about 25,000, in embodiments from about 1,000 to about 5,000,000, in embodiments about 1,000 to about 1,000,000, in embodiments about 1,000 to about 500,000, in embodiments about 1,000 to about 100,000, in embodiments about 1,000 to about 50,000, in embodiments about 1,000 to about 40,000, in embodiments about 1,000 to about 35,000, in embodiments about 1,000 to about 30,000, in embodiments about 1,000 to about 25,000, in embodiments about 500 to about 20,000, in embodiments about 500 to about 15,000, in embodiments about 500 to about 10,000, in embodiments about 500 to about 7,000, in embodiments about 500 to about 5,000, in embodiments about 500 to about 3,000, in embodiments about 500 to about 1,000, in embodiments about 1,000 to about 25,000, in embodiments about 700 to about 20,000, in embodiments about 700 to about 15,000, in embodiments about 700 to about 10,000, in embodiments about 700 to about 7,000, in embodiments about 700 to about 5,000, in embodiments about 700 to about 3,000, in embodiments about 700 to about 1,000, in embodiments about 1,000 to about 25,000, in embodiments about 1,000 to about 20,000, in embodiments about 1,000 to about 15,000, in embodiments about 1,000 to about 10,000, in embodiments about 1,000 to about 7,000, in embodiments about 1,000 to about 5,000, in embodiments about 1,000 to about 3,000, or in embodiments about 1,000 to about 2,000.

[0069] In first embodiments, the weight ratio of the one or more sulfonated polymers to the particles of mineral ore is from about 1 g to about 1000 g of the one or more sulfonated polymers per ton of particles of mineral ore, in embodiments from about 5 g to about 500 g, in embodiments, from about 10 g to about 500 g, in embodiments from about 20 g to about 300 g, in embodiments from about 50 g to about 300 g, in embodiments from about 50 g to about 200 g, in embodiments from about 10 g to about 100 g, in embodiments from about 10 g to about 70 g, in embodiments from about 30 g to about 70 g of the one or more sulfonated polymers per ton of ore.

[0070] The metal oxide ore is in the form of a particulate. In embodiments, 1% to 99% by weight of the particulate has a particle size from about 38 microns to about 250 microns, in embodiments 50% to 80% by weight of the comminuted ore has a particle size from about 38 microns to about 250 microns, in embodiments 60% to about 70% has a particle size from about 38 microns to about 250 microns, in embodiments 65% to 75% has a particle size from about 38 microns to about 250 microns, or in embodiments about 68% to about 72% has a particle size from about 38 microns to about 250 microns as measured by throw-action sieve analysis carried out wet. The procedure for sieve analysis is outlined in American Society for Testing and Materials (ASTM) C 136[2]ASTM C136/C136M-14.

Second Embodiments

[0071] In second embodiments, the modifier of the composition of any of the first embodiments comprises, consists of, or consists essentially of a sulfonated lignin. Lignin is a class of complex organic polymers. Without limitation thereto and solely for the purposes of illustration, lignin may be represented by the structure (VI).

##STR00001##

[0072] In second embodiments the sulfonated lignin has a broad range of molecular weight. In embodiments, the sulfonated lignin has a weight average molecular weight range of from about 1,000 to about 140,000.

[0073] In second embodiments, the sulfonated lignin comprises, consists of, or consists essentially of a byproduct of production of wood pulp using sulfite pumping. In some embodiments, the sulfonated lignin is the reaction product of lignin with one or more sulfites, one or more bisulfites, or a combination thereof.

[0074] In second embodiments, the sulfonated lignin has comprises a modification of structure (VI) wherein one or more of the —CH.sub.2OH groups is replaced with —CH.sub.2SO.sub.3H, —CH.sub.2SO.sub.3.sup.−, or a combination thereof.

[0075] In second embodiments, the sulfonated lignin has a structure comprising structure (VII), structure (VIII), or both structure (VII) and structure (VIII):

##STR00002##

wherein R.sub.1 is hydrogen or one of a wide variety of organic structures found in the structure of lignin; R.sub.2 is one of a wide variety of organic structures found in the structure of lignin; and R.sub.3 is hydrogen or one of a wide variety of organic structures found in the structure of lignin.

Third Embodiments

[0076] In third embodiments, the modifier of the composition of any of the first embodiments comprises, consists of, or consists essentially of a sulfonated starch. In embodiments, the sulfonated starch comprises amylopectin wherein one or more of the —OH groups is replaced with a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−), amylose wherein one or more of the —OH groups is replaced by a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−), or a combination thereof.

Fourth Embodiments

[0077] In fourth embodiments, the modifier of the composition of any of the first embodiments comprises, consists of, or consists essentially of a sulfonated cellulose, wherein one or more of the —OH groups in cellulose molecules is replaced by a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−).

Fifth Embodiments

[0078] In fifth embodiments, the modifier of the composition of any of the first embodiments comprises, consists of, or consists essentially of a sulfonated lignin, a sulfonated starch, a sulfonated cellulose, a sulfonated guar gum, a sulfonated xanthan gum, or any combination thereof.

Sixth Embodiments

[0079] In sixth embodiments, the modifier of the composition of any of the first embodiments comprises one or more sulfonated synthetic polymers. In sixth embodiments, the modifier of the sparge composition of any of the first embodiments comprises one or more sulfonated synthetic polymers, wherein at least one of the one or more sulfonated synthetic polymers comprises a residue of a sulfonated monomer, wherein the sulfonated monomer is selected from sulfonated vinyl alcohol, sulfonated acrylamide, sulfomethylated acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, a salt of 2-acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, a salt of styrene sulfonic acid, and any combination thereof.

[0080] In sixth embodiments, the at least one of the one or more sulfonated synthetic polymers comprises a monomer residue having the structure (IX)

##STR00003##

wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, quaternary organic ammonium; a monomer residue having the structure (X)

##STR00004##

or a combination thereof.

[0081] In sixth embodiments, the at least one of the one or more sulfonated synthetic polymers comprises a monomer residue having the structure (XI)

##STR00005##

wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium;
the monomer residue having the structure (XII)

##STR00006##

the monomer residue having the structure (XIII)

##STR00007##

wherein n is 1, 2, or 3 and the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium;
the monomer residue having the structure (XIV)

##STR00008##

wherein n is 1, 2, or 3;
the monomer residue having the structure (XV)

##STR00009##

the monomer residue having the structure (XVI)

##STR00010##

wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium;
the monomer residue having the structure (XVII)

##STR00011##

the monomer residue having the structure (XVIII)

##STR00012##

wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium;
the monomer residue having the structure (XIX)

##STR00013##

wherein R.sub.4 is alkyl;
the monomer residue having the structure (XX)

##STR00014##

wherein R.sub.4 is alkyl and wherein the sulfonate counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium;
the monomer residue having the structure (XXI)

##STR00015##

the monomer residue having the structure (XXII)

##STR00016##

wherein the sulfonate counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; or any combination thereof.

[0082] In some such sixth embodiments, the at least one of the one or more sulfonated synthetic polymers further comprises the residue of acrylamide, the residue of acrylic acid, the residue of an acrylic acid salt, the residue of methacrylic acid, the residue of a methacrylic acid salt, the residue of maleic acid, the residue of a salt of maleic acid, the residue of a monoester of maleic acid, the residue of salt of a monoester of maleic acid, the residue of a diester of maleic acid, the residue having the structure (XXIII)

##STR00017##

or any combination thereof. In embodiments, the cation of the acrylic acid salt, the residue of the methacrylic acid salt, the residue of the salt of maleic acid, or the residue of the salt of the monoester of maleic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

[0083] In sixth embodiments, the modifier of the sparge composition of any of the first embodiments comprises, consists of, or consists essentially of a copolymer of acrylic acid and/or a salt of acrylic acid with ATBS. In embodiments, the cation of the salt of the acrylic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium. In embodiments, the ATBS is an ATBS salt, wherein the cation is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

[0084] In embodiments, the modifier of the sparge composition of any of the first embodiments comprises, consists of, or consists essentially of a terpolymer of acrylic acid and/or a salt of acrylic acid, ATBS, and acrylamide. In embodiments, the cation of the salt of the acrylic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium. In embodiments, the ATBS is an ATBS salt, wherein the cation is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

Seventh Embodiments

[0085] In seventh embodiments, there is provided a method comprising sparging the sparge composition of any one of the first to sixth embodiments to yield a froth comprising tailings of gangue and a sparged slurry comprising a concentrate of beneficiary; and separating at least a portion of the concentrate from the sparged slurry. In embodiments, the sparging the sparge composition yields a sparged composition, the sparged composition comprising, consisting of, or consisting essentially of an upper froth layer and a lower slurry layer. In some such embodiments, the lower slurry layer comprises water and a slurry of the concentrate and the upper froth layer comprises the tailings. In some such embodiments, the method comprises separating the upper froth layer from the lower slurry layer. Therefore the separating the at least the portion of concentrate from the tailings is accomplished by means known in the art. In embodiments, the separating comprises, consists of, or consists essentially of: tapping off at least a portion of the upper froth layer, skimming off at least a portion of the upper froth layer, depositing at least a portion of the upper froth layer onto a launder, decanting at least a portion of the upper froth layer, or any combination thereof.

Eighth Embodiments

[0086] In eighth embodiments, there is provided a method of froth flotation, the method comprising, consisting of, or consisting essentially of forming a sparge composition, the sparge composition comprising (i) a medium, (ii) an ore, (iii) an amine collector, and (iv) a modifier comprising one or more sulfonated polymers; and sparging the sparge composition to yield a sparged composition, the sparged composition comprising, consisting of, or consisting essentially of a froth and a sparged slurry, wherein the sparged slurry comprises a concentrate of a beneficiary and wherein the froth comprises tailings of a gangue, and the gangue comprises, consists of, or consists essentially of a silicate silica, carbonate, or any combination thereof. In embodiments, the ore comprises, consists of, or consists essentially of an iron ore. In embodiments, the beneficiary comprises, consists of, or consists essentially of an iron oxide. In embodiments, the iron oxide is selected from magnetite, hematite, goethite, limonite, or any combination thereof. In embodiments, the beneficiary comprises, consists of, or consists essentially of magnetite. In embodiments, the method further comprises separating at least a portion of the concentrate of the beneficiary from the sparged composition. In embodiments, the medium comprises, consists of, or consists essentially of water.

[0087] In eighth embodiments, the gangue comprises, consists of, or consists essentially of calcite, dolomite, clay, or any combination thereof. In embodiments, the metal oxide ore comprises, consists of, or consists essentially of an iron ore. In some such embodiments, the iron ore comprises magnetite.

[0088] In eighth embodiments, the sparge composition has a pH from 1-3, in embodiments 3-6, in embodiments 4-7, in embodiments 6-10, in embodiments 11-14, in embodiments 4.5 to 5.5, in embodiments, 4.7 to 5.3, or in embodiments 5.0 to 5.2.

[0089] In eighth embodiments, the sparge composition of the method comprises, consists of, or consists essentially of: water; a metal oxide ore comprising magnetite and further comprising silica, a silicate or a combination thereof; the amine collector; and the modifier comprising the one or more sulfonated polymers.

[0090] In eighth embodiments, the one or more sulfonated polymers is selected from a sulfonated natural polymer, a sulfonated synthetic polymer, and a combination thereof.

[0091] In eighth embodiments the weight average molecular weight of the sulfonated synthetic polymer is from about 300 to about 5,000,000, in embodiments about 300 to about 1,000,000, in embodiments about 300 to about 500,000, in embodiments about 300 to about 100,000, in embodiments about 300 to about 50,000, in embodiments about 300 to about 35,000, in embodiments about 300 to about 30,000, in embodiments about 300 to about 25,000, in embodiments from about 500 to about 5,000,000, in embodiments about 500 to about 1,000,000, in embodiments about 500 to about 500,000, in embodiments about 500 to about 100,000, in embodiments about 500 to about 50,000, in embodiments about 500 to about 25,000, in embodiments from about 700 to about 5,000,000, in embodiments about 700 to about 1,000,000, in embodiments about 700 to about 500,000, in embodiments about 700 to about 100,000, in embodiments about 700 to about 50,000, in embodiments about 700 to about 25,000, in embodiments from about 1,000 to about 5,000,000, in embodiments about 1,000 to about 1,000,000, in embodiments about 1,000 to about 500,000, in embodiments about 1,000 to about 100,000, in embodiments about 1,000 to about 50,000, in embodiments about 1,000 to about 40,000, in embodiments about 1,000 to about 35,000, in embodiments about 1,000 to about 30,000, in embodiments about 1,000 to about 25,000, in embodiments about 500 to about 20,000, in embodiments about 500 to about 15,000, in embodiments about 500 to about 10,000, in embodiments about 500 to about 7,000, in embodiments about 500 to about 5,000, in embodiments about 500 to about 3,000, in embodiments about 500 to about 1,000, in embodiments about 1,000 to about 25,000, in embodiments about 700 to about 20,000, in embodiments about 700 to about 15,000, in embodiments about 700 to about 10,000, in embodiments about 700 to about 7,000, in embodiments about 700 to about 5,000, in embodiments about 700 to about 3,000, in embodiments about 700 to about 1,000, in embodiments about 1,000 to about 25,000, in embodiments about 1,000 to about 20,000, in embodiments about 1,000 to about 15,000, in embodiments about 1,000 to about 10,000, in embodiments about 1,000 to about 7,000, in embodiments about 1,000 to about 5,000, in embodiments about 1,000 to about 3,000, or in embodiments about 1,000 to about 2,000.

[0092] In eighth embodiments, the weight ratio of the one or more sulfonated polymers to the particulate comprising the metal oxide ore in the sparge composition of the method of the eighth embodiments is from about 1 g to about 1000 g of the one or more sulfonated polymers per ton of particulate, in embodiments from about 5 g to about 500 g, in embodiments, from about 10 g to about 500 g, in embodiments from about 20 g to about 300 g, in embodiments from about 50 g to about 300 g, in embodiments from about 50 g to about 200 g, in embodiments from about 10 g to about 100 g, in embodiments from about 10 g to about 70 g, or in embodiments from about 30 g to about 70 g of the one or more sulfonated polymers per particulate.

Ninth Embodiments

[0093] In ninth embodiments, the modifier of the composition of the method of the seventh or eighth embodiments comprises, consists of, or consists essentially of a sulfonated lignin. Lignin is a class of complex organic polymers.

[0094] In ninth embodiments the sulfonated lignin has a broad range of molecular weight. In embodiments, the sulfonated lignin has a weight average molecular weight range of from about 1,000 to about 140,000.

[0095] In ninth embodiments, the sulfonated lignin comprises, consists of, or consists essentially of a byproduct of production of wood pulp using sulfite pumping. In some embodiments, the sulfonated lignin is the reaction product of lignin with one or more sulfites, one or more bisulfites, or a combination thereof.

[0096] In ninth embodiments, the sulfonated lignin has comprises a modification of structure (I) wherein one or more of the —CH.sub.2OH groups is replaced with —CH.sub.2SO.sub.3H, —CH.sub.2SO.sub.3.sup.−, or a combination thereof.

[0097] In ninth embodiments, the sulfonated lignin has a structure comprising structure (II), structure (III), or both structure (II) and structure (III), wherein R.sub.1 is hydrogen or one of a wide variety of organic structures found in the structure of lignin; R.sub.2 is one of a wide variety of organic structures found in the structure of lignin; and R.sub.3 is hydrogen or one of a wide variety of organic structures found in the structure of lignin.

Tenth Embodiments

[0098] In tenth embodiments, the modifier of the composition of the method of the seventh or eighth embodiments comprises, consists of, or consists essentially of a sulfonated starch. In embodiments, the sulfonated starch comprises amylopectin wherein one or more of the —OH groups is replaced with a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−), amylose wherein one or more of the —OH groups is replaced by a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−), or a combination thereof.

Eleventh Embodiments

[0099] In eleventh embodiments, the modifier of the composition of any of the methods of the seventh or eighth embodiments comprises, consists of, or consists essentially of a sulfonated cellulose, wherein one or more of the —OH groups in cellulose molecules is replaced by a sulfonate group (—SO.sub.3H and/or —SO.sub.3.sup.−).

Twelfth Embodiments

[0100] In twelfth embodiments, the modifier of the composition of any of the methods of the seventh or eighth embodiments comprises, consists of, or consists essentially of a sulfonated natural polymer selected from sulfonated lignin, sulfonated starch, sulfonated cellulose, sulfonated guar gum, sulfonated xanthate gum, and any combination thereof.

Thirteenth Embodiments

[0101] In thirteenth embodiments, the modifier of the composition of the methods of the seventh or eighth embodiments comprises a sulfonated synthetic polymer. In thirteenth embodiments, the modifier of the sparge composition of any of the methods of the seventh or eighth embodiments comprises a sulfonated synthetic polymer, wherein the sulfonated synthetic polymer comprises a residue of a sulfonated monomer, wherein the sulfonated monomer is selected from sulfonated vinyl alcohol, sulfonated acrylamide, sulfomethylated acrylamide, 2-acrylamido-2-methylpropane sulfonic acid and/or a salt thereof (ATBS), styrene sulfonic acid and/or a salt thereof, and any combination thereof.

[0102] In thirteenth embodiments, the sulfonated synthetic polymer comprises a monomer residue selected from the monomer residue having the structure (IX), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; the monomer residue having the structure (X); the monomer residue having the structure (XI), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; the monomer residue having the structure (XII); the monomer residue having the structure (XIII), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, quaternary organic ammonium; the monomer residue having the structure (XIV); the monomer residue having the structure (XV); the monomer residue having the structure (XVI), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; the monomer residue having the structure (XVII); the monomer residue having the structure (XVIII), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; the monomer residue having the structure (XIX), wherein R.sub.4 is alkyl; the monomer residue having the structure (XX), wherein R.sub.4 is alkyl and wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; the monomer residue having the structure (XXI); the monomer residue having the structure (XXII), wherein the counterion is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium; and any combination thereof.

[0103] In some such thirteenth embodiments, the sulfonated synthetic polymer further comprises the residue of acrylamide, the residue of acrylic acid, the residue of an acrylic acid salt, the residue of methacrylic acid, the residue of a methacrylic acid salt, the residue of maleic acid, the residue of a salt of maleic acid, the residue of a monoester of maleic acid, the residue of salt of a monoester of maleic acid, the residue of a diester of maleic acid, the residue having the structure (XXIII), or any combination thereof. In embodiments, the cation of the acrylic acid salt, the residue of the methacrylic acid salt, the residue of the salt of maleic acid, or the residue of the salt of the monoester of maleic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

[0104] In thirteenth embodiments, the modifier of the sparge composition of the methods of the seventh or eighth embodiments comprises, consists of, or consists essentially of a copolymer of acrylic acid and ATBS. In embodiments, the cation of the salt of the acrylic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium. In embodiments, the ATBS is an ATBS salt, wherein the cation is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

[0105] In thirteenth embodiments, the modifier of the sparge composition of any of the methods of the seventh or eighth embodiments comprises, consists of, or consists essentially of a terpolymer of acrylic acid, ATBS, and acrylamide. In embodiments, the cation of the salt of the acrylic acid is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium. In embodiments, the ATBS is an ATBS salt, wherein the cation is selected from NH.sub.4.sup.+, Na.sup.+, K.sup.+, primary organic ammonium, secondary organic ammonium, tertiary organic ammonium, and quaternary organic ammonium.

[0106] In thirteenth embodiments, at least one of the one or more sulfonated polymers of any one of the methods of the seventh or eighth embodiments comprises a residue of a monomer, wherein the monomer is selected from sulfonated vinyl alcohol, sulfonated acrylamide, sulfomethylated acrylamide, 2-acrylamido-2-methylpropane sulfonic acid and/or a salt thereof (ATBS), styrene sulfonic acid and/or a salt thereof, and any combination thereof. In some such embodiments, the at least one of the one or more sulfonated polymers further comprises a residue of a monomer selected from acrylic acid, methacrylic acid, acrylamide, vinyl alcohol, maleic acid, maleic acid esters, and any combination thereof. In some such embodiments, the at least one of the one or more sulfonated polymers further comprises a residue acrylic acid, a salt of acrylic acid, or a combination thereof. In some such embodiments, the at least one of the one or more sulfonated polymers comprises the residue of ATBS, the residue of a sulfomethylated acrylamide, or both the residue of ATBS and the residue of sulfomethylated acrylamide.

[0107] In embodiments, the modifier of any of the methods of the seventh and eighth embodiments comprises a naphthalene sulfonate formaldehyde condensate, sulfonated poly(thiophene-3-[2-(2-methoxyethoxy)ethoxy]-2,5-diyl), or a combination thereof.

Fourteenth Embodiments

[0108] In fourteenth embodiments, at least one of the one or more sulfonated polymers of any of the first to thirteenth embodiments is tagged with a fluorescent tag. In embodiments, the fluorescent tag is copolymerized into the backbone of the at least one of the one or more sulfonated polymers or the fluorescent tag is otherwise covalently bonded to the at least one of the one or more sulfonated polymers. In embodiments, the fluorescent tag is selected from the group consisting of hydroxy allyloxy propyl naphthalimide (HAPNQ), pyrene tetrasulfonic acid (PTSA), naphthalene disulfonic acid, and 4-methoxy-N-(3-dimethylaminopropyl)-naphthalimide vinylbenzyl chloride quat (VBNQ). In embodiments, the fluorescent tag is about 2% to about 5% by weight of the one or more sulfonated polymers.

[0109] In fourteenth embodiments, the modifier of any of the first to thirteenth embodiments comprises a fluorescent tag material. In such embodiments, the ratio by weight of the fluorescent tag material to the one or more sulfonated polymers is from about 2:98 to about 5:95. In some such embodiments, the fluorescent tag material is selected from the group consisting of hydroxy allyloxy propyl naphthalimide (HAPNQ), pyrene tetrasulfonic acid (PTSA), naphthalene disulfonic acid, and VBNQ.

Fifteenth Embodiments

[0110] In fifteenth embodiments, the method of any one of the seventh to fourteenth embodiments further comprises grinding a mineral ore to form the particulate comprising the metal ore.

Sixteenth Embodiments

[0111] In sixteenth embodiments, the method of the fifteenth embodiments further comprises the step of combining the particulate with at least a portion of the medium to form a medium-ore slurry.

Seventeenth Embodiments

[0112] In seventeenth embodiments, the method of any one of the sixteenth embodiments further comprises desliming the metal ore.

Eighteenth Embodiments

[0113] In eighteenth embodiments, the method of any one of the sixteenth or seventeenth embodiments further comprises combining the particulate with at least a portion of the modifier, the amine collector, or the modifier and the amine collector to form a modifier/collector-ore slurry, and conditioning the particulate.

NINETEENTH EMBODIMENTS

[0114] In nineteenth embodiments, the method of any of the seventh to eighteenth embodiments comprises grinding a mineral ore to form the particulate comprising the metal ore; and combining the particulate with the modifier, the amine collector, and the medium to make the sparge composition.

Twentieth Embodiments

[0115] In twentieth embodiments, there is provided a use of any of the sparge compositions of the first to sixth embodiments in the beneficiation of iron ore by reverse froth flotation to furnish a beneficiary comprising iron oxide.

[0116] The foregoing may be better understood by reference to the following examples, which are presented for purposes of illustration and are not intended to limit the scope of the invention. In particular the examples demonstrate representative examples of principles innate to the invention and these principles are not strictly limited to the specific condition recited in these examples. As a result it should be understood that the invention encompasses various changes and modifications to the examples described herein and such changes and modifications can be made without departing from the spirit and scope of the invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

EXAMPLES

[0117] Separation of an iron ore into a concentrate and tailings was conducted using a sulfonate polymer as modifier. The iron oxide comprised magnetite and a silica gangue.

Example 1: Aqueous Polymers

[0118] Six aqueous polymers were synthesized as in TABLE 1:

TABLE-US-00001 TABLE 1 Aqueous polymers Weight average Aqueous Actives, molecular Polymer Composition wt % weight, g/mole E Sodium salt of poly(acrylic 35 25,000-30,000 acid-co-sulfomethylated acrylamide) F Sodium salt of poly(acrylic 35 25,000-30,000 acid-co-sulfomethylated acrylamide), tagged with less than 2% hydroxyl allyloxy propyl naphthalimide quaternary salt (HAPNQ)

Example 2: Sparge Test of Iron Ore Sample

[0119] A sample of flotation feed slurry was taken an iron ore beneficiation plant. The iron ore sample was mainly composed of magnetite with silica impurity. Its main composition, solids concentration, pH, and size are shown in TABLE 2.

TABLE-US-00002 TABLE 2 Composition of Iron Ore Slurry Composition Total Fe % SiO.sub.2 % Solids % pH Size* 66.7-67 5.6-5.8 39-40 7.9-8 85%-325 mesh *As measured by throw-action sieve analysis carried out wet.

[0120] Reverse flotation was performed in a Denver D-12 flotation machine. Iron ore slurry at pH 7.9-8 was used for flotation without further dilution. Four separate reverse flotation tests were performed as shown in TABLE 3. A C13 ether diamine having the formula (V) was used as collector in each of the tests. Tests 1 and 2 were performed without modifier, Test 3 with Polymer E as modifier, and Test 4 with Polymer F as modifier. Each of the modifiers and collectors was prepared as a 1% solution in deionized water. The concentrate and tailings (froth) were filtered, dried, weighed, and sent for total iron and SiO.sub.2 assay by X-ray analysis.

The tests results are shown in TABLE 3 and FIG. 1. In comparison, addition of sulfonated polymer E and F improves silica removal and iron recovery.

TABLE-US-00003 TABLE 3 Sparge Tests with Iron Ore Slurry Concentrate Modifier Grade Aqueous Grade of of Test Aqueous Polymer Collector Yield, Fe, SiO.sub.2 Recovery Removal # polymer g/t kg/t % % % of Fe, % of SiO.sub.2 1 None 0 20 94.29 91.06 7.15 95.37 16.61 2 None 0 30 92.21 91.38 6.86 93.6 21.74 3 E 50 30 92.89 92.39 6.5 94.59 24.61 4 F 50 30 93.16 91.55 6.66 94.69 23.03 t = ton