Amine-aldehyde resins and uses thereof in separation processes

Abstract

Amine-aldehyde resins are disclosed for removing a wide variety of solids and/or ionic species from the liquids in which they are suspended and/or dissolved. These resins are especially useful as froth flotation depressants, for example in the beneficiation of value materials (e.g., bitumen, coal, or kaolin clay) to remove impurities such as sand. The resins are also useful for treating aqueous liquid suspensions to remove solid particulates, as well as for removing metallic ions in the purification of water.

What is claimed is: 
     
         1 . A method for beneficiation of an ore, comprising:
 adding a urea-formaldehyde resin to an aqueous slurry comprising an ore to produce a mixture, wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 4,000, and wherein the mixture comprises about 400 grams to about 1,000 grams of the urea-formaldehyde resin per metric ton of the ore;   forcing air through the mixture to form a hydrophilic fraction in the mixture; and   separating a product comprising a mineral or metal from the hydrophilic fraction.   
     
     
         2 . The method of  claim 1 , wherein the mineral or metal comprises phosphate, potash, lime, sulfate, gypsum, iron, platinum, gold, palladium, titanium, molybdenum, copper, uranium, chromium, tungsten, manganese, magnesium, lead, zinc, clay, coal, silver, graphite, nickel, bauxite, borax, or borate. 
     
     
         3 . The method of  claim 1 , wherein the mineral or metal comprises phosphate, iron, copper, or coal. 
     
     
         4 . The method of  claim 1 , wherein the mineral or metal comprises iron. 
     
     
         5 . The method of  claim 1 , wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 1,200, and wherein the mixture comprises about 400 grams to about 600 grams of the urea-formaldehyde resin per metric ton of the ore. 
     
     
         6 . The method of  claim 1 , wherein the urea-formaldehyde resin comprises a cyclic urea-formaldehyde resin that is formed by reacting a monomer mixture comprising about 0.1 mole to about 1 mole urea, about 0.1 mole to about 3 moles formaldehyde, and about 0.1 mole to about 1 mole ammonia. 
     
     
         7 . The method of  claim 1 , wherein the urea-formaldehyde resin is stabilized by reacting with an alcohol comprising methanol, ethanol, n-propanol, isopropanol, n-butanol, or isobutanol. 
     
     
         8 . The method of  claim 1 , wherein the urea-formaldehyde resin and the aqueous slurry are mixed from 30 seconds to 10 minutes prior to forcing air through the mixture, and wherein the mixing occurs at a pH of about 3.0 to about 7.0. 
     
     
         9 . The method of  claim 1 , wherein the mineral or metal comprises iron, wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 1,200, and wherein the mixture comprises about 400 grams to about 600 grams of the urea-formaldehyde resin per metric ton of the ore. 
     
     
         10 . The method of  claim 1 , wherein the aqueous slurry has a solids content of about 10 wt % to about 50 wt %. 
     
     
         11 . The method of  claim 1 , further comprising adding one or more chelating agents to the aqueous slurry to form the mixture. 
     
     
         12 . The method of  claim 1 , wherein the one or more chelating agents comprise hydroxyethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, diethyltriaminepentaacetic, or nitrilotriacetic acid. 
     
     
         13 . The method of  claim 1 , further comprising adding one or more additives to the aqueous slurry to form the mixture, wherein the one or more additives comprise fatty acids, amines, xanthate, guar gum, sodium hexametaphosphate, methylisobutylcarbinol, pine oil, or polypropylene oxides. 
     
     
         14 . A method for beneficiation of an ore, comprising:
 dispersing a urea-formaldehyde resin in an aqueous slurry comprising an ore to produce a mixture, wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 4,000, and wherein the mixture comprises about 400 grams to about 1,000 grams of the urea-formaldehyde resin per metric ton of the ore;   bubbling air through the mixture to form a relatively hydrophobic fraction in the mixture and a relatively hydrophilic fraction in the mixture, wherein the relatively hydrophobic fraction floats toward a surface of the mixture and the relatively hydrophilic fraction sinks toward a bottom of the mixture; and   separating a product comprising a mineral or metal from either the hydrophobic fraction or the hydrophilic fraction.   
     
     
         15 . The method of  claim 14 , wherein the mineral or metal comprises phosphate, potash, lime, sulfate, gypsum, iron, platinum, gold, palladium, titanium, molybdenum, copper, uranium, chromium, tungsten, manganese, magnesium, lead, zinc, clay, coal, silver, graphite, nickel, bauxite, borax, or borate. 
     
     
         16 . The method of  claim 14 , wherein the mineral or metal comprises iron. 
     
     
         17 . The method of  claim 16 , wherein the product is separated from the hydrophilic fraction. 
     
     
         18 . The method of  claim 14 , wherein the mineral or metal comprises iron, wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 1,200, and wherein the mixture comprises about 400 grams to about 600 grams of the urea-formaldehyde resin per metric ton of the ore. 
     
     
         19 . A method for beneficiation of an ore, comprising:
 preparing a mixture comprising a urea-formaldehyde resin and an aqueous slurry comprising an ore, wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 4,000, and wherein the mixture comprises about 400 grams to about 1,000 grams of the urea-formaldehyde resin per metric ton of the ore;   contacting the mixture with air to form a hydrophilic fraction in the mixture; and   separating a product comprising iron from the hydrophilic fraction.   
     
     
         20 . The method of  claim 19 , wherein the urea-formaldehyde resin has a number average molecular weight of about 400 to about 1,200, and wherein the mixture comprises about 400 grams to about 600 grams of the urea-formaldehyde resin per metric ton of the ore.