Cationic polymer selective depressants and use thereof in mineral ore purification methods
AssigneeKemira Oyj
InventorsMarcelo Moreira Costa, Xihui Yin, Sergio Cabo
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Abstract
The present embodiments generally relate to a technology for improving Cu/Mo grade by the addition of cationic polymers as selective depressants for acid insoluble matters, e.g., silicates and/or clays, in the flotation circuit. Various types of cationic polymers are demonstrated to be effective depressants including polyamine, polyDADMAC, and cationic polyacrylamide. Also disclosed are processes for enriching a desired mineral from an ore comprising the desired mineral and gangue, wherein the process comprises carrying out a flotation process in the presence of one or more cationic polymer depressants.
Claims72
A metal purification process wherein one or more metals are purified from a composition comprising the metal and insoluble silicate and/or clay mineral contaminants, wherein said purification process includes at least one flotation step, and at least one of said flotation steps include the addition of at least one cationic polymer which functions as a depressant for the insoluble silicates and/or clay minerals.
A process for enriching a desired mineral from an ore comprising the desired mineral and gangue which comprises insoluble silicate and/or clay mineral contaminants, wherein the process comprises carrying out at least one flotation process in the presence of one or more of depressants, wherein at least one of said depressants comprises a cationic polymer.
A process for enriching a desired mineral from an ore comprising the desired mineral and gangue which comprises any or all of the following contaminants:
- insoluble silicates;
- carbonates;
- sulfides;
- clay;
- oxides of aluminum, oxides of iron, silica (e.g. quartz), titanium, sulfur and alkaline earth metals;
- amphibole, talc, quartz, muscovite, sericite, biotite, chlorites, pyrite, feldspar, mica, clinocloro, and serpentine, wherein the process comprises carrying out at least one flotation process in the presence of one or more of depressants, wherein at least one of said depressants comprises a cationic polymer.
The process of any of the foregoing claims wherein the metal which is purified is in the form of a metal sulfide.
The process of any of the foregoing claims wherein the metal which is purified is selected from copper, molybdenum, gold, zinc, lead, nickel, niobium, platinum, palladium, rhodium, ruthenium, iridium, and osmium.
The process of any of the foregoing claims wherein the metal which is purified comprises copper.
The process of any of the foregoing claims wherein the metal which is purified comprises molybdenum.
The process of any one of the foregoing claims, wherein the metal which is purified comprises zinc.
The process of any of the foregoing claims wherein the amount (percent by weight) of insoluble contaminants in the impure metal containing composition or gangue ranges from 1% to 70%.
The process of any of the foregoing claims wherein the mole percent of cationic monomers in the cationic polymer ranges from 1% to 100% with the proviso that the resultant cationic polymer has an overall positive (cationic) charge.
The process of any of the foregoing claims wherein the mole percent of cationic monomers in the cationic polymer ranges from 1-5%, 5-10%, 10-20%, 20-30%, 30-40%, 40-50%, 50-60%, 60-70%, 70-80%, 80-90%, or 90-100%.
The process of any of the foregoing claims wherein the cationic polymer predominantly or exclusively comprises cationic monomers.
The process any of the foregoing claims wherein the cationic polymer depressant comprises cationic monomers and further comprises anionic and/or or neutral monomers.
The process any of the foregoing claims wherein the cationic polymer depressant is water soluble.
The process any of the foregoing claims wherein the cationic polymer depressant comprises or consists of an acrylamide-containing polymer.
The process any of the foregoing claims wherein the cationic polymer depressant comprises or consists of polyacrylamide, copolymers of acrylamide, sulfonated polyacrylamide, cationic polyacrylamide, and partially hydrolyzed acrylamide.
The process any of the foregoing claims wherein the cationic polymer depressant comprises or consists of acrylamide or partially hydrolyzed acrylamide and one or more cationic monomers.
The process any of the foregoing claims wherein the cationic polymer depressant comprises or consists of cationic monomers which include by way of example dialkylaminoalkyl acrylates and methacrylates and their quaternary or acid salts, such as dimethylaminoethyl acrylate methyl chloride quaternary salt, dimethylaminoethyl acrylate methyl sulfate quaternary salt, dimethyaminoethyl acrylate benzyl chloride quaternary salt, dimethylaminoethyl acrylate sulfuric acid salt, dimethylaminoethyl acrylate hydrochloric acid salt, diethylaminoethyl acrylate, methyl chloride quaternary salt, dimethylaminoethyl methacrylate methyl chloride quaternary salt, dimethylaminoethyl methacrylate methyl sulfate quaternary salt, dimethylaminoethyl methacrylate benzyl chloride quaternary salt, dimethylaminoethyl methacrylate sulfuric acid salt, dimethylaminoethyl methacrylate hydrochloric acid salt, dimethylaminoethyl methacryloyl hydrochloric acid salt, dialkylaminoalkylacrylamides or methacrylamides and their quaternary or acid salts such as acrylamidopropyltrimethylammonium chloride, dimethylaminopropyl acrylamide methyl sulfate quaternary salt, dimethylaminopropyl acrylamide sulfuric acid salt, dimethylaminopropyl acrylamide hydrochloric acid salt, methacrylamidopropyltrimethylammonium chloride, dimethylaminopropyl methacrylamide methyl sulfate quaternary salt, dimethylaminopropyl methacrylamide sulfuric acid salt, dimethylaminopropyl methacrylamide hydrochloric acid salt, diethylaminoethylacrylate, diethylaminoethylmethacrylate and diallyldialkylammonium halides such as diallyldiethylammonium chloride and diallyldimethyl ammonium chloride.
The process any of the foregoing claims wherein the cationic polymer depressant comprises or consists of acrylamide or partially hydrolyzed acrylamide and one or more cationic monomers.
The process any of the foregoing claims wherein the cationic polymer depressant comprises acrylamide or partially hydrolyzed acrylamide and one or more cationic monomers.
The process any of the foregoing claims wherein the cationic polymer depressant comprises about 10% to about 60% cationic monomers by weight.
The process any of the foregoing claims wherein the cationic polymer depressant comprises a cationic polyacrylamide.
The process any of the foregoing claims wherein the cationic polymer depressant is a copolymer comprising one or more cationic monomers and acrylamide monomers.
The process any of the foregoing claims wherein a pre-treatment agent for use with said process is a cationic polyacrylamide having a molecular weight (MW) in the range of 200,000-2,000,000 g/mol.
The process any of the foregoing claims wherein the cationic polymer depressant comprises cationic polyacrylamide having an average molecular weight (MW) in the range of 400,000-2,000,000 g/mol, typically 400,000-1,900,000, more typically 500,000-1,900,000, preferably 1,000,000-1,900,000 g/mol, more preferably 1,200,000-1,900,000 g/mol.
The process any of the foregoing claims wherein the cationic polymer depressant is a cationic polyacrylamide may be produced by copolymerizing acrylamide with a cationic monomer or methacrylamide with a cationic monomer, e.g., methacryloyloxyethyl-trimethylammonium chloride, acryloyloxyethyltrimethyl ammonium chloride, methacrylamidopropyltrimethylammonium chloride, acrylamidopropyltri methyl-ammonium chloride, diallyldimethylammonium chloride, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide, or a similar monomer.
The process any of the foregoing claims wherein the cationic polymer depressant is a cationic polyacrylamide comprising a copolymer of acrylamide or methacrylamide with methacryloyloxyethyltrimethyl ammonium chloride optionally containing other monomers, with the proviso its net charge is cationic and comprising an acrylamidelmethacrylamide backbone.
The process any of the foregoing claims wherein the cationic polymer depressant comprises an acrylamide or methacrylamide based polymer which optionally is rendered cationic after polymerization by an aftertreatment such as Hofmann or Mannich reactions.
The process any of the foregoing claims wherein the cationic polymer depressant comprises homo- or co-polymers made up from at least one monomer belonging to the group of diallyldimethylammonium chloride (DADMAC), vinylpyridinium chloride, N-vinylimidazoline chloride, vinylbenzyltrimethylammonium chloride acryloyl-oxyethyl-trimethylammoniumchloride, acryloyloxyethyl-benzyldimethyl-ammoniumchloride, methacryloyloxyethyl-trimethylammoniumchloride, methacryloyl-oxyethyl-benzyldimethyl-ammoniumchloride, acrylamidopropyltrimethyl-ammoniumchloride (TMAPAA), acrylamidopropyl-benzyl-dimethylammoniumchloride (BDMAPAA), methacryl-amidopropyl-trimethylammonium-chloride (TMAPMA), and methacrylamidopropyl-benzyldimethylammoniumchloride (BDMAPMA).
The process of any of the foregoing claims wherein the cationic polymer depressant comprises a cationic coagulant polymer, e.g., polydiallyldimethylammonium chloride (polyDADMAC).
The process of any of the foregoing claims wherein the cationic polymer depressant is synthesized by using a controlled molecular weight cationic polyacrylamide polymerized within a coagulant matrix, e.g., comprising [3-(methacryloylamino)propyl] trimethylammonium chloride (MAPTAC), polydiallyldimethylammonium chloride (poly-DADMAC), polyamine, polyyinylamine, dimethylaminoethylacrylate methyl chloride or any of their mixtures.
The process of any of the foregoing claims wherein the cationic polymer depressant is selected from a group comprising cationic polyacrylamide, polydiallyldimethylammonium chloride (poly-DADMAC), polyamine, cationic starch and chitosan, and further wherein said cationic polyacrylamide may be obtained by copolymerizing acrylamide with a cationic monomer or methacrylamide with a cationic monomer, wherein said cationic monomer may be selected from the group consisting methacryloyloxyethyltrimethyl ammonium chloride, acryloyloxyethyltrimethyl ammonium chloride, 3-(methacrylamido) propyltrimethyl ammonium chloride, 3-(acryloylamido) propyltrimethyl ammonium chloride, diallyldimethyl ammonium chloride, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide, and similar monomers.
The process of any of the foregoing claims wherein the cationic polymer depressant is a copolymer of acrylamide or methacrylamide with (meth)acryloyloxyethyltrimethyl ammonium chloride, optionally containing other monomers, as long as its net charge is cationic and it has an acrylamide/methacrylamide backbone.
The process of any of the foregoing claims wherein the cationic polymer depressant includes one or more cationic polymer flocculants.
The process of any of the foregoing claims wherein the cationic polymer is selected from the following:
- a) a cationic polymer comprising repeating units of one or more amine monomers;
- b) a cationic polymer comprising repeating units of one or more diallyldimethylammonium chloride monomers (polyDADMAC);
- c) a cationic polymer comprising repeating units of one or more acrylamide monomers;
- and d) a cationic polymer comprising repeating subunits of one or more cationic monomers;
- or e) any combination or mixture of the foregoing.
A process for enriching a desired mineral from an ore comprising the desired mineral and gangue, wherein the process comprises carrying out a flotation process in the presence of one or more of the foregoing cationic polymer depressants according to any of the foregoing claims.
A process of using a cationic polymer as a depressant in a flotation process.
Dependencies are inferred from the claim text.