CA1157585A - Crosslinked starches as depressants in mineral ore flotation - Google Patents
Crosslinked starches as depressants in mineral ore flotationInfo
- Publication number
- CA1157585A CA1157585A CA000386235A CA386235A CA1157585A CA 1157585 A CA1157585 A CA 1157585A CA 000386235 A CA000386235 A CA 000386235A CA 386235 A CA386235 A CA 386235A CA 1157585 A CA1157585 A CA 1157585A
- Authority
- CA
- Canada
- Prior art keywords
- starch
- crosslinked
- flotation
- depressants
- crosslink
- 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.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/001—Flotation agents
- B03D1/004—Organic compounds
- B03D1/016—Macromolecular compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/001—Flotation agents
- B03D1/004—Organic compounds
- B03D1/008—Organic compounds containing oxygen
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/02—Froth-flotation processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D2201/00—Specified effects produced by the flotation agents
- B03D2201/06—Depressants
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D2203/00—Specified materials treated by the flotation agents; specified applications
- B03D2203/02—Ores
- B03D2203/04—Non-sulfide ores
Abstract
TITLE: CROSSLINKED STARCHES AS DEPRESSANTS IN MINERAL
ORE FLOTATION
ABSTRACT OF THE DISCLOSURE
Conventional starches are chemically crosslinked for use as selective depressants in the flotation of non-sulfide mineral ores. The process employing these cross-linked starches requires lower reagent dosages,exhibits improved selectivity and recovery and exerts a lower load on existing waste treatment facilities. The crosslinking agents employed are bifunctional and are used in sufficient quantities to result in 500 to 10,000 anhydroglucose units per crosslink.
ORE FLOTATION
ABSTRACT OF THE DISCLOSURE
Conventional starches are chemically crosslinked for use as selective depressants in the flotation of non-sulfide mineral ores. The process employing these cross-linked starches requires lower reagent dosages,exhibits improved selectivity and recovery and exerts a lower load on existing waste treatment facilities. The crosslinking agents employed are bifunctional and are used in sufficient quantities to result in 500 to 10,000 anhydroglucose units per crosslink.
Description
7 5 ~ 5 TIT~E: CROSSLINKED STARCHES AS DEPRSSSANTS IN MINERAL
O~E FLOT~TIO~ ~~ ~
BACKGROUND OF THE INVENTION
__ .
In mineral ore flotation, depression comprises steps taken to prevent the flotation of a particular miner-al. In one-mineral flotation systems, it is commonly prac ticed to hold dawn both the gangue materials and low-assay middlings. In differential flotation systems, it is used to hold back one or more of the materials normally flotable by a given collector.
Depression is conventionally accomplished throu~h the use of reagents kncwn as depressing agents or, more commonly, depressants. When added to the flotation systems, the depressing agents exert a specific action upon the ma-terial to be depressed thereby preventing that material from floating. The exact mode of this action remains open to specula~ion. Various theories have been put forth to explain thîs action; some of which include: that the depres-sants react chemicaLly with the mineral surface to produce insoluble protective films of a wettable nature which fail to react with collectors; that the depressants, by various physical-chemical mechanisms, such as surface adsorption, mass-action effects, complex formation, or the like, pre vent the formation of the collector film; that the depres-sants act as solvents for an activating film naturally associated with the mineral; that the depressants act as - solvents for the collecting film; and the like. These theories appear closely related and the correct theory may 1 ~75~
ultimately prove to involve elements from several, if not all, of them.
Currently, non-sulfide flotation systems have utilized depressants derived from natural substances such as s~arches, dextrins, gums and the like. See U.S. Patent ~o. 3,292,780 to Frommer et al. and U.S. Patent No.
3,371,778 to Iwasaki.` However, from an ecological vantage point, the presence of residual depressants such as these in the waste waters increase the biodegradeable oxygen demand and the chemica~ oxygen demand, thereby creating a pollution problem in the disposal of these waste waters.
From a commercial vantage point, there are an ever-increas-ing number of countries in which use of reagents having a food value, s~ch as starch, is prohibited in commercial applications.
In the industry's effort to overcome the disadvan-tages inherent in systems employing natural substances~
such as starch, as the depressant, various synthetic depre-sants have been examined. Although it is too early to ac-curately judge the effectiveness of these synthetic depres-sants, a major obstacle they will have to overcome is their exorbitant cost as compared to the natural depressants.
Accordingly, there yet exists the need for a se-lective depressant which can at once overcome the drawbacks ~5 of the conventional depressants derived from natural sub-stances and yet perform in an equivalent or superior manner without incurring exorbitant expenses.
SUMMARY OF THE INVENTION
The present invention provides a process for de-3a pressing non-sulfide minerals in a flotation system. The process comprises adding to the flotation system an effec-tive amount of a crosslinked starch or starch-containing substance having from about 500 to lO,OOO anhydroglucose units per crosslink. The crosslinking is the result o~
reacting the starch or starch-containing substance with a bifunctional crosslinking agent under appropriate reaction 1 1~7'~
conditions. The instant process depresses non sul~ide min-erals as well as comparable processes employing synthetic depressants or starch depressants at dosage levels consid-erably less than those employed in processes utilizing starch and more economically than processes using synthetic depressants.
DETAILED DESCRIPTION OF THE IN~ENTION
In accordance with the instant invention there is provided a process for depressing non-sulfide minerals in a flotation system by adding to the flotation system an effec-tive amount of crosslinked starch. Starches, or starch-containing natural substances, which can be utilized in the instant invention include, but are not limited to, corn, waxy corn, waxy maize, tapioca, potato, sorghum, wheat, rice, sago, amylomaize, arrowroot and the like. Addition-ally, starches, such as those listed above, which have been modified may be utilized. Examples of various modificakions include starches which have been acidified, oxidized, fluidized, enzyme converted, dextrinized, esterified, ether-ified, grafted, block polymerized and the like. What ismeant by these terms is, in esterification for example, the starch is reacted with acetic anhydride or maleic anhydride to become esteri~ied.
The starch or modified starch is crosslinked with an appropriate bifunctional crosslinking agent. Suitable crosqlinking agents able to react with two or more hydroxyl groups include phosphorus oxychloride, trimetaphosphates, epichlorohydrin, dicarboxylic acid anhydride, N,N'-methyl-enebisacrylamide; 2,4,6-trichloro-s-triazine and the like.
The degree of crosslinking should be such that there are 500 to 10,000 anhydroglucose units (AGU) per crosslink. To obtain this level of crosslinking about 0.001 to 0.15 per-cent, based on the starch, of crosslinking reagent should be employed~ preferably 0.01 to 0.15 percent.
. The crosslinking a~ent is added to a granular starch suspension generally having a solids content on the order of 35 to 45~. The crosslinking reaction lasts from 7~3 5 one to twenty-four hour at a temperature within the range of 10 to 110C. with the pH controlled between pH 7 to 12.
I~ the suspension is a swelling one, such as an aqueous suspensionl the swelling under strongly alkaline conditions can be controlled by the presence of high concentrations (10 to 30%) of sodium chloride or sulfate. The swellin~ of the starch results from the alkali hydroxide, ammonium hydroxide, amine or alkali carbonate generally employed to maintain the pH. Conditions under this reaction are gener-ally chosen to prevent gelatinization so that the reactionproduct can be isolated in granule form.
To obtain a higher degree of substitution, the crosslinking reaction may be carried out in a non-swelling suspension, such as isopropanol, or by blending the reagents with a starch having a 5 to 20% moisture content without any suspending medium. Additionally, the crosslinking reaction can occur in a cooked a~ueous starch solution where the starch has gelatinized; in this reaction the temperature must be maintained between 60 and 100C., and the gelatinized ~tarch can also be dried on a heated drum.
Although the effective amount of the crosslinked starch necessary to obtain effective depression may vary depending upon the mineral to be treated, the degree of - substitution and similar variables, generally an effective 25 amount will be 0.25 to 2.5 pounds of crosslinked starch per ton of ore and preferably 0.5 to 1.5 pounds per ton of ore.
The ores which can be treated are believed to be all non-sulfide ores with special emphasis being ~iven to the sep-aration of siliceous gangue particles from oxidic iron 3Q values, of copper minerals from molybdenite, of galena from chalcopyrite and sphalerite, of apatite from ilmenite, of fluorspar from calcite and of sylvite from halite in the presence of clays.
The follcwing specific examples illustrate certain aspects of the present invention and, more particularly, point out methods of evaluating the process for depressin~
non-sulfide minerals in a flotation system. Hcwever, the 1 ~S7535 examples are set forth for illustration only and are not to be construed as limitations on the presen~ invention except as set forth in the appended claims. All parts and percent-ages are by weight unless otherwise specified.
EXPERIMENTAL PROCEDURE
Step 1: Grindin~
600 Parts of crude iron ore having a particle size of minus 10 mesh are mixed with 400 ml. of deionized water, 5.0 ~1. of a 2~ sodium silicate "N" solution and 1.8 ml. of a 25% NaOH solution.
The resulting mixture is subjected to grinding in a rod mill for 50 minutes and thereafter is transferred into a 8 liter cylinder. To this cylinder there are added 200 ml. of 0.05% Ca(OH)2 solution and an amount of deion-ized water sufficient to fill the cylinder to the 8 litermark.
Step 2: Deslimin~
The cylinder mixture is subjected to mechanical stirring for 1 minute during which time there is added 6.9 ~0 parts of a 1% cau ticized corn starch solution (0.011 NaOH
based on starch) as the desliming aid. The stirring is then stopped and the mixture is allowed to settle for 12 minutes, after which approximately 7 liters of the supernatant layer is syphoned off and filtered, resulting in the slime product.
Step 3: Rou~her Float The remaining 1 liter underflcw is transferred to a flotation bowl and water containing 17 ppm of calcium as CaC03 is added to the bowl until the level reaches the lip.
The pulp is briefly agitated at 1200 rpm and thereafter the pH is adjusted to approximately 10.6 through the addition of 5-10 drops of 10% NaOH. 27.3 Parts of a 1% causticized starch solution is then added as a depressant and a two-minute conditioning time is allowed.
4.9 Parts of a 1% solution of a commercially available collector is added, 3Q seconds of conditioning is allowed followed by a four-minute float. After the float, ~.3 parts of a 1~ solution of a commercially available col~
1 ~575~5 ~ 6 -collector is added, 30 seconds of conditionin~ is allowed followed by a four-minute ~loat. After the fLoat, 3.3 parts of a 1% solution of a commercially available col-lector is again added, 30 seconds of conditioning is allowed and then followed by a second four-minute float.
The froth collected from the first and second floats is labeled the rougher float and the remainder in the flotation bowl is labeled the roughèr concentrate.
Step 4: Scaven~er Float The rougher float is transferred to a second flo-tation bowl to which there is added 13.6 parts of a 1%
causticized corn starch solution as a depressant. Two minutes of conditioning is allowed before air is introduced into this bowl for 3-4 minutes. The froth collected is labeled the final froth.
Step 5: Middling Float The underflow from the scavenger float is further conditioned for 30 seconds with 1.4 parts of a 1~ solution of a commercially available collector and thereafter floated for 3 minutes. The middling float sequence is repeated a second time and the combined froth from these two float is labeled the middling froth. The underflow remaining is combined with the rougher concentrate and labeled the con-centrate.
COMPARATIVE EXAMPLE A
The Experimental Procedure set forth above is followed in every material detail employing as the depres-sant 1.5 pounds of causticized starch per long ton of iron ore in the flotation steps. Test results are set forth in 3Q Table I.
COMPARATIVE EXAMPLE B
The Experimental Procedure set forth above is followed in every material detail employing as the depres-sant 0.75 pound of causticized starch per long ton of iron ore in the flotation steps. T~st results are set forth in Table I.
.~
S ~ !;
The Experimental Procedure set forth above is followad in every material detail employing as the depres-sant 1.5 pounds of crosslinked starch per long ton of iron ore in the flotation steps wherein the crosslinked starch is an ethoxylated cornstarch crosslinked with epichlorohy-drin and mixed with 7.7% NaOH in a blender for 15 seconds.
Test results are set ~orth in Table I.
The procedure of Example 1 is followed in every material detail except that 0.75 pound of crosslinked starch is employed as the depressant are set forth in Table I.
COMPARATIVE EXAMPLE C
The Experimental Procedure set forth above is lS followed in every material detail employing as the depres sant 1.5 pounds of ethoxylated corn starch mixed with 7.7%
NaOH in a blender for 15 seconds per long ton o~ iron ore in the flotation steps. Test results are set forth in Table I.
The procedure of Example 1 is followed in every material detail exeept that 1.0 pound of crosslinked starch is employed as the depressant per long ton of iron ore.
Test results are set forth in Table II.
The procedure of Example 3 is followed in every material detail except that the crosslinked cornstarch is mixed with 2~ NaO~ and blended for 5 seconds. Test results are set forth in Table II.
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O~E FLOT~TIO~ ~~ ~
BACKGROUND OF THE INVENTION
__ .
In mineral ore flotation, depression comprises steps taken to prevent the flotation of a particular miner-al. In one-mineral flotation systems, it is commonly prac ticed to hold dawn both the gangue materials and low-assay middlings. In differential flotation systems, it is used to hold back one or more of the materials normally flotable by a given collector.
Depression is conventionally accomplished throu~h the use of reagents kncwn as depressing agents or, more commonly, depressants. When added to the flotation systems, the depressing agents exert a specific action upon the ma-terial to be depressed thereby preventing that material from floating. The exact mode of this action remains open to specula~ion. Various theories have been put forth to explain thîs action; some of which include: that the depres-sants react chemicaLly with the mineral surface to produce insoluble protective films of a wettable nature which fail to react with collectors; that the depressants, by various physical-chemical mechanisms, such as surface adsorption, mass-action effects, complex formation, or the like, pre vent the formation of the collector film; that the depres-sants act as solvents for an activating film naturally associated with the mineral; that the depressants act as - solvents for the collecting film; and the like. These theories appear closely related and the correct theory may 1 ~75~
ultimately prove to involve elements from several, if not all, of them.
Currently, non-sulfide flotation systems have utilized depressants derived from natural substances such as s~arches, dextrins, gums and the like. See U.S. Patent ~o. 3,292,780 to Frommer et al. and U.S. Patent No.
3,371,778 to Iwasaki.` However, from an ecological vantage point, the presence of residual depressants such as these in the waste waters increase the biodegradeable oxygen demand and the chemica~ oxygen demand, thereby creating a pollution problem in the disposal of these waste waters.
From a commercial vantage point, there are an ever-increas-ing number of countries in which use of reagents having a food value, s~ch as starch, is prohibited in commercial applications.
In the industry's effort to overcome the disadvan-tages inherent in systems employing natural substances~
such as starch, as the depressant, various synthetic depre-sants have been examined. Although it is too early to ac-curately judge the effectiveness of these synthetic depres-sants, a major obstacle they will have to overcome is their exorbitant cost as compared to the natural depressants.
Accordingly, there yet exists the need for a se-lective depressant which can at once overcome the drawbacks ~5 of the conventional depressants derived from natural sub-stances and yet perform in an equivalent or superior manner without incurring exorbitant expenses.
SUMMARY OF THE INVENTION
The present invention provides a process for de-3a pressing non-sulfide minerals in a flotation system. The process comprises adding to the flotation system an effec-tive amount of a crosslinked starch or starch-containing substance having from about 500 to lO,OOO anhydroglucose units per crosslink. The crosslinking is the result o~
reacting the starch or starch-containing substance with a bifunctional crosslinking agent under appropriate reaction 1 1~7'~
conditions. The instant process depresses non sul~ide min-erals as well as comparable processes employing synthetic depressants or starch depressants at dosage levels consid-erably less than those employed in processes utilizing starch and more economically than processes using synthetic depressants.
DETAILED DESCRIPTION OF THE IN~ENTION
In accordance with the instant invention there is provided a process for depressing non-sulfide minerals in a flotation system by adding to the flotation system an effec-tive amount of crosslinked starch. Starches, or starch-containing natural substances, which can be utilized in the instant invention include, but are not limited to, corn, waxy corn, waxy maize, tapioca, potato, sorghum, wheat, rice, sago, amylomaize, arrowroot and the like. Addition-ally, starches, such as those listed above, which have been modified may be utilized. Examples of various modificakions include starches which have been acidified, oxidized, fluidized, enzyme converted, dextrinized, esterified, ether-ified, grafted, block polymerized and the like. What ismeant by these terms is, in esterification for example, the starch is reacted with acetic anhydride or maleic anhydride to become esteri~ied.
The starch or modified starch is crosslinked with an appropriate bifunctional crosslinking agent. Suitable crosqlinking agents able to react with two or more hydroxyl groups include phosphorus oxychloride, trimetaphosphates, epichlorohydrin, dicarboxylic acid anhydride, N,N'-methyl-enebisacrylamide; 2,4,6-trichloro-s-triazine and the like.
The degree of crosslinking should be such that there are 500 to 10,000 anhydroglucose units (AGU) per crosslink. To obtain this level of crosslinking about 0.001 to 0.15 per-cent, based on the starch, of crosslinking reagent should be employed~ preferably 0.01 to 0.15 percent.
. The crosslinking a~ent is added to a granular starch suspension generally having a solids content on the order of 35 to 45~. The crosslinking reaction lasts from 7~3 5 one to twenty-four hour at a temperature within the range of 10 to 110C. with the pH controlled between pH 7 to 12.
I~ the suspension is a swelling one, such as an aqueous suspensionl the swelling under strongly alkaline conditions can be controlled by the presence of high concentrations (10 to 30%) of sodium chloride or sulfate. The swellin~ of the starch results from the alkali hydroxide, ammonium hydroxide, amine or alkali carbonate generally employed to maintain the pH. Conditions under this reaction are gener-ally chosen to prevent gelatinization so that the reactionproduct can be isolated in granule form.
To obtain a higher degree of substitution, the crosslinking reaction may be carried out in a non-swelling suspension, such as isopropanol, or by blending the reagents with a starch having a 5 to 20% moisture content without any suspending medium. Additionally, the crosslinking reaction can occur in a cooked a~ueous starch solution where the starch has gelatinized; in this reaction the temperature must be maintained between 60 and 100C., and the gelatinized ~tarch can also be dried on a heated drum.
Although the effective amount of the crosslinked starch necessary to obtain effective depression may vary depending upon the mineral to be treated, the degree of - substitution and similar variables, generally an effective 25 amount will be 0.25 to 2.5 pounds of crosslinked starch per ton of ore and preferably 0.5 to 1.5 pounds per ton of ore.
The ores which can be treated are believed to be all non-sulfide ores with special emphasis being ~iven to the sep-aration of siliceous gangue particles from oxidic iron 3Q values, of copper minerals from molybdenite, of galena from chalcopyrite and sphalerite, of apatite from ilmenite, of fluorspar from calcite and of sylvite from halite in the presence of clays.
The follcwing specific examples illustrate certain aspects of the present invention and, more particularly, point out methods of evaluating the process for depressin~
non-sulfide minerals in a flotation system. Hcwever, the 1 ~S7535 examples are set forth for illustration only and are not to be construed as limitations on the presen~ invention except as set forth in the appended claims. All parts and percent-ages are by weight unless otherwise specified.
EXPERIMENTAL PROCEDURE
Step 1: Grindin~
600 Parts of crude iron ore having a particle size of minus 10 mesh are mixed with 400 ml. of deionized water, 5.0 ~1. of a 2~ sodium silicate "N" solution and 1.8 ml. of a 25% NaOH solution.
The resulting mixture is subjected to grinding in a rod mill for 50 minutes and thereafter is transferred into a 8 liter cylinder. To this cylinder there are added 200 ml. of 0.05% Ca(OH)2 solution and an amount of deion-ized water sufficient to fill the cylinder to the 8 litermark.
Step 2: Deslimin~
The cylinder mixture is subjected to mechanical stirring for 1 minute during which time there is added 6.9 ~0 parts of a 1% cau ticized corn starch solution (0.011 NaOH
based on starch) as the desliming aid. The stirring is then stopped and the mixture is allowed to settle for 12 minutes, after which approximately 7 liters of the supernatant layer is syphoned off and filtered, resulting in the slime product.
Step 3: Rou~her Float The remaining 1 liter underflcw is transferred to a flotation bowl and water containing 17 ppm of calcium as CaC03 is added to the bowl until the level reaches the lip.
The pulp is briefly agitated at 1200 rpm and thereafter the pH is adjusted to approximately 10.6 through the addition of 5-10 drops of 10% NaOH. 27.3 Parts of a 1% causticized starch solution is then added as a depressant and a two-minute conditioning time is allowed.
4.9 Parts of a 1% solution of a commercially available collector is added, 3Q seconds of conditioning is allowed followed by a four-minute float. After the float, ~.3 parts of a 1~ solution of a commercially available col~
1 ~575~5 ~ 6 -collector is added, 30 seconds of conditionin~ is allowed followed by a four-minute ~loat. After the fLoat, 3.3 parts of a 1% solution of a commercially available col-lector is again added, 30 seconds of conditioning is allowed and then followed by a second four-minute float.
The froth collected from the first and second floats is labeled the rougher float and the remainder in the flotation bowl is labeled the roughèr concentrate.
Step 4: Scaven~er Float The rougher float is transferred to a second flo-tation bowl to which there is added 13.6 parts of a 1%
causticized corn starch solution as a depressant. Two minutes of conditioning is allowed before air is introduced into this bowl for 3-4 minutes. The froth collected is labeled the final froth.
Step 5: Middling Float The underflow from the scavenger float is further conditioned for 30 seconds with 1.4 parts of a 1~ solution of a commercially available collector and thereafter floated for 3 minutes. The middling float sequence is repeated a second time and the combined froth from these two float is labeled the middling froth. The underflow remaining is combined with the rougher concentrate and labeled the con-centrate.
COMPARATIVE EXAMPLE A
The Experimental Procedure set forth above is followed in every material detail employing as the depres-sant 1.5 pounds of causticized starch per long ton of iron ore in the flotation steps. Test results are set forth in 3Q Table I.
COMPARATIVE EXAMPLE B
The Experimental Procedure set forth above is followed in every material detail employing as the depres-sant 0.75 pound of causticized starch per long ton of iron ore in the flotation steps. T~st results are set forth in Table I.
.~
S ~ !;
The Experimental Procedure set forth above is followad in every material detail employing as the depres-sant 1.5 pounds of crosslinked starch per long ton of iron ore in the flotation steps wherein the crosslinked starch is an ethoxylated cornstarch crosslinked with epichlorohy-drin and mixed with 7.7% NaOH in a blender for 15 seconds.
Test results are set ~orth in Table I.
The procedure of Example 1 is followed in every material detail except that 0.75 pound of crosslinked starch is employed as the depressant are set forth in Table I.
COMPARATIVE EXAMPLE C
The Experimental Procedure set forth above is lS followed in every material detail employing as the depres sant 1.5 pounds of ethoxylated corn starch mixed with 7.7%
NaOH in a blender for 15 seconds per long ton o~ iron ore in the flotation steps. Test results are set forth in Table I.
The procedure of Example 1 is followed in every material detail exeept that 1.0 pound of crosslinked starch is employed as the depressant per long ton of iron ore.
Test results are set forth in Table II.
The procedure of Example 3 is followed in every material detail except that the crosslinked cornstarch is mixed with 2~ NaO~ and blended for 5 seconds. Test results are set forth in Table II.
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s ~1 ., 1 r n ¦ ~ O 2 ~¦
~ ~ ~l ~ ~ "~ 4e4e 1~ ~ --¦ o cr~ U O ~ ~ O ~ o
2 il ~ D¦ `O `O ~_ ~ a _.
ol ~ 0 -~
_ D D ~
:~ '11 u~
E;l `oO I
U~ ~ ~
~ ~1 ~1 _ ol ~ i .
7~
When the Experimental Procedure set forth above is employed in the flotation process wherein copper is separated from moly~denite, depression performance substan-tially equivalent to that achieved in an iron ore flotationsystem is obtained employing a N~N'-methylenebisacrylamide crosslinked amylomaize starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein galena is separated from chalcopyrite and sphalerite, depression performance substantially equivalent to that achieved in an iron ore flotation system is obtained employin~ an epichlor-ohydrin crosslinked dextrinized potato starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein apatite is separated from ilmenite, depression performance substanti.
lly equivalent to that achieved in an iron ore flotation system is obtained employing a trimetaphosphate crosslinked sorghum starch.
;
When the Experimen~al Procedure set forth above is employed in the flotation process wherein fluorspar is separated from calcite, depression performance substantially equivalent to that achieved in an iron ore flotation system i9 obtained employing an epichlorohydrin crosslinked etheri-fied rice starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein sylvite is separated from halite and clay, depression performance substantially equivalent to that achieved in an iron ore flotation system is obtained employing a N,N'-methylenebis-acrylamide crosslinked tapioca starchO
ol ~ 0 -~
_ D D ~
:~ '11 u~
E;l `oO I
U~ ~ ~
~ ~1 ~1 _ ol ~ i .
7~
When the Experimental Procedure set forth above is employed in the flotation process wherein copper is separated from moly~denite, depression performance substan-tially equivalent to that achieved in an iron ore flotationsystem is obtained employing a N~N'-methylenebisacrylamide crosslinked amylomaize starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein galena is separated from chalcopyrite and sphalerite, depression performance substantially equivalent to that achieved in an iron ore flotation system is obtained employin~ an epichlor-ohydrin crosslinked dextrinized potato starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein apatite is separated from ilmenite, depression performance substanti.
lly equivalent to that achieved in an iron ore flotation system is obtained employing a trimetaphosphate crosslinked sorghum starch.
;
When the Experimen~al Procedure set forth above is employed in the flotation process wherein fluorspar is separated from calcite, depression performance substantially equivalent to that achieved in an iron ore flotation system i9 obtained employing an epichlorohydrin crosslinked etheri-fied rice starch.
When the Experimental Procedure set forth above is employed in the flotation process wherein sylvite is separated from halite and clay, depression performance substantially equivalent to that achieved in an iron ore flotation system is obtained employing a N,N'-methylenebis-acrylamide crosslinked tapioca starchO
Claims (9)
1. A process for depressing non-sulfide minerals in a flotation system which comprises adding to the flota-tion system, as a selective depressant, an effective amount of a crosslinked starch or starch-containing substance having from about 500 to 10,000 anhydroglucose units per crosslink.
2. The process of Claim 1 wherein the starch is selected from the group consisting of corn starch, waxy corn starch, tapioca starch, potato starch, sorghum starch, wheat starch, rice starch, sago starch, amylomaize starch and arrowroot starch.
3. The process of Claim 2 where the starch has been modified by either acidification, oxidation, fluidiza-tion, enzyme conversion, dextrinization, esterification, etherification, graftation, or block polymerization.
4. The process of Claim 1 wherein 0.001 to 0.15 percent, based on the starch, of a crosslinking reagent is employed to crosslink the starch, which latter starch prod-uct can be in the original granular form, as an aqueous dispersion or in a drum dried form.
5. The process of Claim 4 wherein the crosslink-ing agent is selected form the goup consisting of epichlo-rohydrin, N,N'-methylenebisacrylamide, 2,4,6-trichloro-s-triazine, dicarboxylic acid anhydrides, phosphorus oxychlo-ride and trimetaphosphates.
6. The process of Claim 1 wherein the selective depressant is an epichlorohydrin crosslinked cornstarch.
7. The process of Claim 1 wherein the non-sulfide mineral is oxidized iron ore.
8. The process of Claim 1 wherein the effective amount is from about 0.25 to 2.5 pounds of crosslinked starch per ton of ore.
9. The process of Claim 6 wherein the non-sulfide mineral is oxidized iron ore.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/213,532 US4339331A (en) | 1980-12-05 | 1980-12-05 | Crosslinked starches as depressants in mineral ore flotation |
| US213,532 | 1980-12-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1157585A true CA1157585A (en) | 1983-11-22 |
Family
ID=22795466
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000386235A Expired CA1157585A (en) | 1980-12-05 | 1981-09-18 | Crosslinked starches as depressants in mineral ore flotation |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US4339331A (en) |
| BR (1) | BR8107882A (en) |
| CA (1) | CA1157585A (en) |
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| JPS61501155A (en) * | 1984-02-03 | 1986-06-12 | スコツト・ペ−パ−・カンパニ− | Modified polysaccharide material |
| US4808301A (en) * | 1987-11-04 | 1989-02-28 | The Dow Chemical Company | Flotation depressants |
| US5693692A (en) * | 1988-05-02 | 1997-12-02 | Huntsman Petrochemical Corp. | Depressant for flotation separation of polymetallic sulphide ores |
| US4877517A (en) * | 1988-05-02 | 1989-10-31 | Falconbridge Limited | Depressant for flotation separation of polymetallic sulphidic ores |
| US5049612A (en) * | 1988-05-02 | 1991-09-17 | Falconbridge Limited | Depressant for flotation separation of polymetallic sulphidic ores |
| US5030340A (en) * | 1990-06-08 | 1991-07-09 | American Cyanamid Company | Method for the depressing of hydrous silicates and iron sulfides with dihydroxyalkyl polysaccharides |
| US5074994A (en) * | 1990-10-18 | 1991-12-24 | The Doe Run Company | Sequential and selective flotation of sulfide ores |
| US5078860A (en) * | 1991-02-06 | 1992-01-07 | The Doe Run Company | Sequential and selective flotation of sulfide ores containing copper and molybdenum |
| US5106489A (en) * | 1991-08-08 | 1992-04-21 | Sierra Rutile Limited | Zircon-rutile-ilmenite froth flotation process |
| US5307938A (en) * | 1992-03-16 | 1994-05-03 | Glenn Lillmars | Treatment of iron ore to increase recovery through the use of low molecular weight polyacrylate dispersants |
| US5533626A (en) * | 1995-06-07 | 1996-07-09 | Cytec Technology Corp. | Method of depressing non-sulfide silicate gangue minerals |
| US5525212A (en) * | 1995-06-07 | 1996-06-11 | Cytec Technology Corp. | Method of depressing non-sulfide silicate gangue minerals |
| US5507395A (en) * | 1995-06-07 | 1996-04-16 | Cytec Technology Corp. | Method of depressing non-sulfide silicate gangue minerals |
| US5531330A (en) * | 1995-06-07 | 1996-07-02 | Cytec Technology Corp. | Method of depressing non-sulfide silicate gangue minerals |
| US5851959A (en) * | 1997-01-03 | 1998-12-22 | Chemstar Products Company | High temperature stable modified starch polymers and well drilling fluids employing same |
| US6713038B2 (en) | 2000-04-18 | 2004-03-30 | Millenium Inorganic Chemicals, Inc. | TiO2 compounds obtained from a high silica content ore |
| US8971913B2 (en) * | 2003-06-27 | 2015-03-03 | Qualcomm Incorporated | Method and apparatus for wireless network hybrid positioning |
| FR2879209B1 (en) | 2004-12-09 | 2007-09-07 | Roquette Freres | NOVEL AQUEOUS ADHESIVE COMPOSITIONS CONTAINING A LOW TEMPERATURE RETICULATED WHEAT STARCH |
| US8127930B2 (en) * | 2004-12-23 | 2012-03-06 | Georgia-Pacific Chemicals Llc | Amine-aldehyde resins and uses thereof in separation processes |
| US8702993B2 (en) | 2004-12-23 | 2014-04-22 | Georgia-Pacific Chemicals Llc | Amine-aldehyde resins and uses thereof in separation processes |
| US8011514B2 (en) * | 2004-12-23 | 2011-09-06 | Georgia-Pacific Chemicals Llc | Modified amine-aldehyde resins and uses thereof in separation processes |
| US8757389B2 (en) | 2004-12-23 | 2014-06-24 | Georgia-Pacific Chemicals Llc | Amine-aldehyde resins and uses thereof in separation processes |
| US7913852B2 (en) | 2004-12-23 | 2011-03-29 | Georgia-Pacific Chemicals Llc | Modified amine-aldehyde resins and uses thereof in separation processes |
| US8092686B2 (en) | 2004-12-23 | 2012-01-10 | Georgia-Pacific Chemicals Llc | Modified amine-aldehyde resins and uses thereof in separation processes |
| US8252866B2 (en) * | 2007-10-19 | 2012-08-28 | Georgia-Pacific Chemicals Llc | Azetidinium-functional polysaccharides and uses thereof |
| PE20100438A1 (en) * | 2008-06-05 | 2010-07-14 | Georgia Pacific Chemicals Llc | COMPOSITION OF AQUEOUS SUSPENSION WITH PARTICLES OF VALUABLE MATERIALS AND IMPURITIES |
| BRPI0902233B1 (en) * | 2009-06-09 | 2021-07-27 | Mosaic Fertilizantes P&K Ltda. | PROCESS FOR OBTAINING APATITA CONCENTRATES BY FLOTATION |
| CN101590450B (en) * | 2009-06-22 | 2011-08-03 | 广西大学 | Method for preparing mineral inhibitor for barite |
| US9102995B2 (en) | 2010-08-09 | 2015-08-11 | Nalco Company | Cross-linked ethylsulfonated dihydroxypropyl cellulose |
| US9199855B2 (en) | 2010-08-09 | 2015-12-01 | Nalco Company | Chemical treatment to improve red mud separation and washing in the bayer process |
| US8298508B2 (en) | 2010-08-09 | 2012-10-30 | Nalco Company | Recovery of alumina trihydrate during the bayer process using cross-linked polysaccharides |
| WO2014022666A1 (en) * | 2012-08-01 | 2014-02-06 | Cornell University | Crosslinked native and waxy starch resin compositions and processes for their manufacture |
| WO2014107491A1 (en) * | 2013-01-03 | 2014-07-10 | Archer Daniels Midland Company | High viscosity crosslinked ethoxy-starch |
| US10427950B2 (en) | 2015-12-04 | 2019-10-01 | Ecolab Usa Inc. | Recovery of mining processing product using boronic acid-containing polymers |
| CN113926591B (en) * | 2021-08-30 | 2023-02-03 | 东北大学 | Multi-efficiency novel reverse flotation inhibitor for iron ore and synthesis and use methods thereof |
| CN113680536B (en) * | 2021-08-30 | 2022-09-09 | 东北大学 | High-carbonate iron ore composite modified inhibitor and preparation and use methods thereof |
| CN114011587B (en) * | 2021-11-03 | 2024-02-23 | 武汉科技大学 | Preparation method of ultrasonic modified starch beneficiation reagent and iron oxide ore reverse flotation method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2364520A (en) * | 1943-06-23 | 1944-12-05 | Minerals Separation North Us | Concentration of sylvinite ores |
| US2689649A (en) * | 1952-05-15 | 1954-09-21 | Int Minerals & Chem Corp | Concentration of sylvite ores |
| US2970140A (en) * | 1957-08-09 | 1961-01-31 | American Maize Prod Co | Process for preparing amino ethers of starch |
| US2975124A (en) * | 1957-08-28 | 1961-03-14 | Nat Starch Chem Corp | Flocculation of fine particles by starch ethers |
| US3292780A (en) * | 1964-05-04 | 1966-12-20 | Donald W Frommer | Process for improved flotation treatment of iron ores by selective flocculation |
| US3371778A (en) * | 1965-02-12 | 1968-03-05 | Univ Minnesota | Method of treating starches for flotation of minerals |
| US3393168A (en) * | 1965-03-04 | 1968-07-16 | Monsanto Co | Crosslinked olefin/maleic anhydride interpolymers |
| US3862028A (en) * | 1971-06-03 | 1975-01-21 | Us Agriculture | Flotation-beneficiation of phosphate ores |
| US3795671A (en) * | 1971-12-21 | 1974-03-05 | Us Agriculture | Epoxypropyl starch |
| HU167599B (en) * | 1973-11-29 | 1975-11-28 | ||
| DE2429428A1 (en) * | 1974-06-19 | 1976-01-08 | Hoechst Ag | Floating non-sulphidic copper ores - with addn of alkyl- or alkyl hydroxyalkyl celluloses as pushers for sludge-forming minerals |
| US3979286A (en) * | 1974-10-16 | 1976-09-07 | The United States Of America As Represented By The Secretary Of Agriculture | Removal of heavy metal ions from aqueous solutions with insoluble cross-linked-starch-xanthates |
| GB1487411A (en) * | 1974-11-19 | 1977-09-28 | Allied Colloids Ltd | Materials and processes for flotation of mineral substances |
| SU688235A1 (en) * | 1975-05-13 | 1979-09-30 | Государственный научно-исследовательский институт горнохимического сырья | Method of direct flotation of phosphorus-containing materials |
-
1980
- 1980-12-05 US US06/213,532 patent/US4339331A/en not_active Expired - Lifetime
-
1981
- 1981-09-18 CA CA000386235A patent/CA1157585A/en not_active Expired
- 1981-12-04 BR BR8107882A patent/BR8107882A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| US4339331A (en) | 1982-07-13 |
| BR8107882A (en) | 1982-09-08 |
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