USE OF ALKOXYLATED AMINES AS COLLECTOR AGENTS FOR ORE BENEFICIATION

Abstract

Provided is a method of beneficiating an ore including contacting an ore with a compound represented by formula (1):

##STR00001##

where the structural variables are defined herein.

Claims

1.-15: (canceled)

16. A method of beneficiating an ore, comprising contacting at least one ore with at least one compound represented by formula (1): ##STR00010## wherein: R.sup.1CO is a saturated or unsaturated, linear or branched acyl group containing 8-24 carbon atoms; R.sup.2 is selected from the group consisting of a direct bond, a C.sub.1-C.sub.20, linear or branched, saturated or unsaturated hydrocarbon chain optionally substituted by one or more OH group(s), a substituted alkylene radical, wherein the alkylene radical is substituted by 1 or 2 OH groups, an alkenylene radical containing from 1-20 carbon atoms, a substituted alkenylene radical, wherein the alkenylene radical is substituted by 1 or 2 methyl and/or methylene groups, a cycloalkylene group, a cycloalkenylene group, and an arylene group; R.sup.4 is a hydrocarbyl group containing 8-24 carbon atoms or a group represented by the formula R.sup.6O-(AO).sub.w-T-, wherein R.sup.6 is a hydrocarbyl group containing 8-24 carbon atoms, w is an integer ranging from 0 to 20, AO is an alkyleneoxy group containing 2-4 carbon atoms, T is an alkylene group containing 1-6 carbon atoms; R.sup.5 is a hydrocarbyl group or a benzyl group; X is a halogen, sulfate, or a carbonate; AO is an alkyleneoxy group containing 2-4 carbon atoms; n is an integer of between 1 and 20; t is 0 or 1; y is 0 or 1; p ranges from 1 to 15; G is a group represented by formula (III): ##STR00011## wherein B is an alkyl containing 1-4 carbon atoms or a benzyl group, s is 1, 2 or 3, R.sup.5, X, and t are as defined above, and wherein the group (CH.sub.2).sub.s is a spacer between the two nitrogen atoms to which it is linked.

17. The method of claim 16, wherein the compound represented by formula (1) is represented by formula (1A): ##STR00012## wherein AO, n, p, t, R.sup.1, R.sup.2, R.sup.4, R.sup.5 and X are as defined in claim 16.

18. The method of claim 17, wherein: R.sup.1CO is a saturated or unsaturated, linear or branched acyl group containing 12-24 carbon atoms; R.sup.2 is an alkylene radical represented by the formula (CH.sub.2).sub.z, wherein z is an integer from 1 to 20; R.sup.4 is a hydrocarbyl group containing 8-24 carbon atoms; and AO, n, p, t, R.sup.5 and X are as defined in claim 17.

19. The method of claim 16, wherein: each t is 1; and R.sup.5 is a methyl or ethyl group.

20. The method of claim 16, wherein: each n is, independently from one another, 1 to 6; and p is from 1 to 10.

21. The method of claim 16, wherein the ore is selected from the group consisting of calcium carbonates, magnesium carbonates, phosphates, iron ores, and mixtures thereof.

22. The method of claim 16, wherein the ore is selected from the group consisting of calcium carbonates, calcium carbonate-containing materials, and mixtures thereof.

23. The method of claim 16, wherein the ore is wollastonite, barite, titanium oxides, kaolin, kaolinitic clays, calcined kaolinitic clays, montmorillonite, sepiolite, talc, diatomaceous earths, aluminium oxides, aluminium oxides containing other elements, or other oxides, sulfates and sulfides, including mixtures thereof.

24. The method of claim 16, wherein the ore is selected from the group consisting of potassium chloride, metal-containing ores, and mixtures thereof, wherein the metal is selected from the group consisting of iron, platinum, aluminium, nickel, copper, and mixtures thereof.

25. The method of claim 16, which at least reduces the content in the ore of at least one mineral selected from the group consisting of graphite, iron sulfides, iron oxides, iron hydroxides, iron oxyhydroxides, silica, silicates, mica, clays, potash, and mixtures thereof.

26. The method of claim 16, wherein the content of the compound represented by formula (1) is from 10 ppm to 5000 ppm by weight relative to the amount of the ore.

27. The method of claim 16, which is a direct flotation process.

28. The method of claim 16, which is an indirect flotation process.

29. A flotation pulp comprising water, ground ore containing impurities, and at least compound represented by formula (1): ##STR00013## wherein: R.sup.1CO is a saturated or unsaturated, linear or branched acyl group containing 8-24 carbon atoms; R.sup.2 is selected from the group consisting of a direct bond, a C.sub.1-C.sub.20, linear or branched, saturated or unsaturated hydrocarbon chain optionally substituted by one or more OH group(s), a substituted alkylene radical, wherein the alkylene radical is substituted by 1 or 2 OH groups, an alkenylene radical containing from 1-20 carbon atoms, a substituted alkenylene radical, wherein the alkenylene radical is substituted by 1 or 2 methyl and/or methylene groups, a cycloalkylene group, a cycloalkenylene group, and an arylene group; R.sup.4 is a hydrocarbyl group containing 8-24 carbon atoms or a group represented by the formula R.sup.6O-(AO).sub.w-T-, wherein R.sup.6 is a hydrocarbyl group containing 8-24 carbon atoms, w is an integer ranging from 0 to 20, AO is an alkyleneoxy group containing 2-4 carbon atoms, T is an alkylene group containing 1-6 carbon atoms; R.sup.5 is a hydrocarbyl group or a benzyl group; X is a halogen, sulfate, or a carbonate; AO is an alkyleneoxy group containing 2-4 carbon atoms; n is an integer of between 1 and 20; t is 0 or 1; y is 0 or 1; p ranges from 1 to 15; G is a group represented by formula (III): ##STR00014## wherein B is an alkyl containing 1-4 carbon atoms or a benzyl group, s is 1, 2 or 3, R.sup.5, X, and t are as defined above, and wherein the group (CH.sub.2).sub.s is a spacer between the two nitrogen atoms to which it is linked.

30. The flotation pulp of claim 29, having at least one of the following characteristics: a solid weight content of the pulp of from 5 wt % to 50 wt %, and a content of the compound represented by formula (1) of from 0.001 wt % to 0.5 wt % based on the solids weight content of the pulp.

31. Tailings comprising floated impurities and at least one compound represented by formula (1): ##STR00015## wherein: R.sup.1CO is a saturated or unsaturated, linear or branched acyl group containing 8-24 carbon atoms; R.sup.2 is selected from the group consisting of a direct bond, a C.sub.1-C.sub.20, linear or branched, saturated or unsaturated hydrocarbon chain optionally substituted by one or more OH group(s), a substituted alkylene radical, wherein the alkylene radical is substituted by 1 or 2 OH groups, an alkenylene radical containing from 1-20 carbon atoms, a substituted alkenylene radical, wherein the alkenylene radical is substituted by 1 or 2 methyl and/or methylene groups, a cycloalkylene group, a cycloalkenylene group, and an arylene group; R.sup.4 is a hydrocarbyl group containing 8-24 carbon atoms or a group represented by the formula R.sup.6O-(AO).sub.w-T-, wherein R.sup.6 is a hydrocarbyl group containing 8-24 carbon atoms, w is an integer ranging from 0 to 20, AO is an alkyleneoxy group containing 2-4 carbon atoms, T is an alkylene group containing 1-6 carbon atoms; R.sup.5 is a hydrocarbyl group or a benzyl group; X is a halogen, sulfate, or a carbonate; AO is an alkyleneoxy group containing 2-4 carbon atoms; n is an integer of between 1 and 20; t is 0 or 1; y is 0 or 1; p ranges from 1 to 15; G is a group represented by formula (III): ##STR00016## wherein B is an alkyl containing 1-4 carbon atoms or a benzyl group, s is 1, 2 or 3, R.sup.5, X, and t are as defined above, and wherein the group (CH.sub.2).sub.s is a spacer between the two nitrogen atoms to which it is linked

32. The tailings of claim 31, comprising, relative to the total weight of the dried tailings, from 50 wt % to 99.995 wt % of floated impurities and from 0.005 wt % to 35 wt % of the compound represented by formula (1).

Description

EXAMPLE 1: SYNTHESIS OF A COLLECTOR A (ACCORDING TO THE INVENTION)

[0120] In a 4 L round bottom flask are introduced 283.5 g of hydrogenated tallow fatty acid and 0.2 g of a 50 wt % aqueous solution of hypophosphorous acid.

[0121] The mixture is heated to 80 C. with nitrogen bubbling. The bubbling is stopped and 109.5 g of adipic acid are then introduced under agitation.

[0122] After 15 minutes, 936 g of ethoxylated coco alkyl amine (5OE) supplied by CECA S.A. under the trade name Noramox C.sub.5 are introduced in a 1 hours' time while increasing the temperature to 120 C.

[0123] Then the mixture is heated to 260 C. and the temperature is maintained until almost all the acid is consumed (Acid value <5). The system is cooled down to recover the sought esteramine product.

[0124] In a second step, in a 2 L round bottom flask, are introduced 1035 g of esteramine product obtained in the previous step and 218 g of isopropyl alcohol. The mixture is heated to 65 C. with nitrogen bubbling. The bubbling is stopped and 203.4 g of DMS (Dimethyl sulphate) are slowly introduced in a 1 hours' time. The temperature is allowed to rise up to 75 C. The mixture is maintained at this temperature for 2 h30 and then let cool down and the product is then recovered, which corresponds to the polymer of adipic acid and hydrogenated tallow fatty acid with ethoxylated coco alkyl amine (5OE), dimethyl sulphate quaternised.

EXAMPLE 2: SYNTHESIS OF A COLLECTOR B (ACCORDING TO THE INVENTION)

[0125] In a 4 L round bottom flask, 567 g of hydrogenated tallow fatty acid are introduced with 0.3 g of a 50 wt % aqueous solution of hypophosphorous acid. The mixture is heated until 80 C. with nitrogen bubbling and 219 g of adipic acid are introduced.

[0126] After 15 minutes, are introduced in al hours' time, 1872 g of ethoxylated coco alkyl amine (5OE) supplied by CECA S.A. under the trade name Noramox C.sub.5 while increasing the temperature to 120 C. The mixture is then heated to 160 C. and the pressure in the vessel is progressively lowered until 50 mm Hg (6.67 kPa) is reached.

[0127] These temperature and low pressure are maintained during 1 h and then the temperature is raised up to 190 C. until almost all the acid is consumed (Acid value <5). The system is cooled down to recover sought esteramine product.

[0128] In a second step, in a 6 L glass reactor, 2000 g of the esteramine product obtained in the previous step are introduced together with 300 g of isopropyl alcohol. Methyl chloride is introduced until the pressure in the vessel reaches 290 kPa. The temperature is maintained at 80-85 C. until complete reaction has occurred.

[0129] Complete reaction is achieved when the total amount of basic nitrogen is less or equal to 0.2 mmol.Math.g.sup.1, as measured by titration with 0.2 N hydrochloric acid in isopropanol. The reactor is let cool down to 65 C. and the pressure back to atmospheric. Nitrogen bubbling in the mixture is maintained during 2 hours before recovering the sought product, which corresponds to the polymer of adipic acid and hydrogenated tallow fatty acid with ethoxylated coco alkyl amine (5OE), chloromethane quaternised.

EXAMPLE 3: SYNTHESIS OF A COLLECTOR C (ACCORDING TO THE INVENTION)

[0130] In a 4 L round bottom flask, are introduce 567 g of hydrogenated tallow fatty acid and 0.3 g of a 50 wt % aqueous solution of hypophosphorous acid. The mixture is heated until 80 C. with nitrogen bubbling and 177.2 g of succinic acid are then introduced. After 15 minutes, 1872 g of ethoxylated coco alkyl amine (5OE) supplied by CECA S.A. under the trade name Noramox C.sub.5 are introduced in a 1 hours' time, while increasing the temperature to 120 C. Then the mixture is heated to 160 C. and the pressure is lower in the vessel progressively until 50 mm Hg (6.67 kPa) is reached.

[0131] These temperature and low pressure are maintained during 1 hour and then the temperature is raised up to 190 C. until almost all the acid is consumed (Acid value <5). The system is cooled down to recover sought esteramine product.

[0132] In a second step, in a 6 L glass reactor, are introduce 2011 g of the esteramine product obtained in the previous step and 306.3 g of isopropyl alcohol. Methyl chloride is introduced until the pressure in the vessel reaches 290 kPa. The temperature is maintained at 80-85 C. until complete reaction has occurred.

[0133] Complete reaction is achieved when the total amount of basic nitrogen is less or equal to 0.2 mmol.Math.g.sup.1, as measured by titration with 0.2 N hydrochloric acid in isopropanol. The reactor is let to cool down to 65 C. and the pressure back to atmospheric. Nitrogen bubbling in the mixture is let during 2 hours before recovering the sought product, which corresponds to the polymer of succinic acid and hydrogenated tallow fatty acid with ethoxylated coco alkyl amine (5OE), chloromethane quaternised.

EXAMPLE 4: SYNTHESIS OF A COLLECTOR D (ACCORDING TO THE INVENTION)

[0134] In a 4 L round bottom flask, are introduced 567 g of hydrogenated tallow fatty acid and 0.3 g of a 50 wt % aqueous solution of hypophosphorous acid. The mixture is heated until 80 C. with nitrogen bubbling and 219 g of adipic acid are introduced.

[0135] After 15 minutes, are introduced in a 1 hours' time, 2034.3 g of ethoxylated tallow alkyl amine (5OE) supplied by CECA S.A. under the trade name Noramox S5 while increasing the temperature to 120 C. The mixture is then heated to 160 C. and the pressure is lowered in the vessel progressively until 50 mm Hg (6.67 kPa) is reached.

[0136] These temperature and low pressure are maintained during 1 hour and then the temperature is raised up to 190 C. until almost all the acid is consumed (Acid value <5). The system is cooled down to recover the sought esteramine product.

[0137] In a second step, in a 6 L glass reactor, are introduced 2005.3 g of the esteramine product obtained in the previous step and 301 g of isopropyl alcohol. Methyl chloride is introduced until the pressure in the vessel reaches 290 kPa. The temperature is maintained at 80-85 C. until complete reaction has occurred.

[0138] Complete reaction is achieved when the total amount of basic nitrogen is less or equal to 0.2 mmol.Math.g.sup.1, as measured by titration with 0.2 N hydrochloric acid in isopropanol. The reactor is let to cool down to 65 C. and the pressure back to atmospheric. Nitrogen bubbling is let during 2 hours in the mixture before recovering the sought product, which corresponds to the polymer of adipic acid and hydrogenated tallow fatty acid with ethoxylated tallow alkyl amine (5OE), chloromethane quaternised.

EXAMPLE 5: SYNTHESIS OF A COLLECTOR E (ACCORDING TO THE INVENTION)

[0139] In a 4 L round bottom flask, are introduced 550.5 g of hydrogenated tallow fatty acid and 0.3 g of a 50 wt % aqueous solution of hypophosphorous acid. The mixture is heated until 80 C. with nitrogen bubbling and 438 g of adipic acid are then introduced. After 15 minutes, are introduced in a 1 hours' time 220.3 g of ethoxylated coco alkyl amine (5OE) supplied by CECA S.A. under the trade name Noramox C.sub.5, while increasing the temperature to 120 C.

[0140] Then the mixture is heated to 160 C. and the pressure is lowered in the vessel progressively until 50 mm Hg (6.67 kPa) is reached. These temperature and low pressure are maintained during 1 hour and then the temperature is raised up to 190 C. until almost all the acid is consumed (Acid value <5). The system is cooled down to recover the sought esteramine product.

[0141] In a second step, in a 6 L glass reactor, are introduced 2001 g of the esteramine product obtained in the previous step together with 301 g of isopropyl alcohol. Methyl chloride is introduced until the pressure in the vessel reaches 290 kPa. The temperature is maintained at 80-85 C. until complete reaction has occurred.

[0142] Complete reaction is achieved when the total amount of basic nitrogen is less or equal to 0.2 mmol.Math.g.sup.1, as measured by titration with 0.2 N hydrochloric acid in isopropanol. The reactor is let to cool down to 65 C. and the pressure back to atmospheric. Nitrogen bubbling in the mixture is maintained during 2 hours before recovering the sought product, which corresponds to the polymer of adipic acid and hydrogenated tallow fatty acid with ethoxylated coco alkyl amine (5OE), chloromethane quaternised.

EXAMPLE 6: SYNTHESIS OF ESTERQUAT FC ACCORDING TO EXAMPLE 2 OF WO 2011/147855 (COMPARATIVE EXAMPLE)

[0143] Alfol C16 (378.4 g), adipic acid (461.2 g) and methyldiethanolamine (285.8 g) are added to a round bottom flask, fitted with a condenser, a thermometer, a heating mantel, a nitrogen inlet and a mechanical stirrer. The temperature of the reaction mixture is gradually raised to 160 C. and the water produced during the reaction is distilled off. The distillation of the water starts at 154 C. and is continued for 1.5 hour at 164 C.-175 C., under atmospheric pressure. Then vacuum is applied 6.67 kPa (50 mm Hg) pressure in the vessel and distillation is continued for 5 more hours. The progress of the reaction is evaluated by the determination of the acid value.

[0144] For the quaternisation reaction, 2125 g of esteramine product obtained in the previous step and 534 g of isopropyl alcohol are introduced in a 6 L glass reactor. Methyl chloride is then introduced until the pressure in the vessel reaches 290 kPa. Temperature is maintained at 80-85 C. until complete reaction has occurred.

[0145] Complete reaction is achieved when the total amount of basic nitrogen is less or equal to 0.2 mmol.Math.g.sup.1, as measured by titration with 0.2 N hydrochloric acid in isopropanol. After reactor cools down to 65 C. and the pressure get back to atmospheric, nitrogen is bubbled in the mixture for 2 hours before recovering the product.

EXAMPLE 7: SYNTHESIS OF ESTERQUAT GC ACCORDING TO EXAMPLE M1 OF WO 2008/089906 (COMPARATIVE EXAMPLE)

[0146] 567 g (2.1 moles) of partly hydrogenated palm oil fatty acid, 219 g (1.5 moles) of adipic acid and 0.3 g of hypophosphoric acid are introduced into a stirred reactor and heated to 70 C. under a reduced pressure of 2 kPa. Triethanolamine (447 g; 3 moles) are then added drop wise in portions and, at the same time, the temperature is raised up to 120 C. After the addition, the reaction mixture is heated to 160 C., the pressure is reduced to 6.67 kPa (50 mm Hg) and the mixture is stirred under those conditions for 2.5 hours, until the acid value falls below 5 mg KOH.Math.g.sup.1. The mixture is then cooled to 60 C., the vacuum is broken by introduction of nitrogen, and 0.6 g of hydrogen peroxide is added in the form of a 30 wt % aqueous solution.

[0147] For the quaternisation step, the resulting ester was dissolved in 376 g of isopropyl alcohol, and 357 g (2.83 moles) of dimethyl sulphate are added to the resulting solution over a period of 1 hour at such a rate that the temperature does not rise above 65 C.

[0148] After the addition, the mixture is stirred for another 2.5 h, the total nitrogen content being regularly checked by sampling. The reaction is terminated when constant total nitrogen content is reached. A product with a solids content of 80 wt % is obtained.

EXAMPLE 8: CALCIUM CARBONATE ORE BENEFICIATION

[0149] The flotation tests are performed in a 2.8 L plastic bowl with the laboratory flotation cell from Outotec.

[0150] 800 g of calcium carbonate ore containing 3.3 wt % impurities are mixed with 2.4 L of water in the plastic bowl of the flotation cell. The turbine agitation speed is set up to 1200 rpm to insure a total suspension of the ore in the cell.

[0151] Final beneficiation is obtained in two flotation steps run in the same cell one after the other. First step lasts 8 minutes and second step 14 minutes.

[0152] Before each step, the slurry is conditioned during 2 minutes with the collector before introducing the air in the cell. The air flow rate is set to 2 L.Math.min.sup.1. During flotation experiment, froth is removed regularly with a plastic spatula and collected for analysis.

[0153] The purified carbonate sample is filtrated, weighed after drying and analysed. Hydrochloric acid attack is followed by a second drying and weighing in order to measure the amount of acidic insoluble compounds (remaining silicates). The HCl attack aims at obtaining a complete dissolution of calcium carbonate by an appropriate dissolution with concentrated hydrochloric acid solution (typically 10 wt % in water). The remaining minerals that are not digested correspond to the silicates (impurities).

[0154] The froth is also rinsed and filtrated. It is then dried, weighed, submitted to HCl attack, dried and weighed again in order to deduce the amount of impurities and the calcium carbonate losses.

[0155] Results are expressed as calcite ore purity after treatment and loss of ore during treatment. Target is an as high as possible purity with loss as low as possible. Results are considered acceptable if purity is over 99.85 wt % and loss below 5 wt %.

[0156] In order to get more significant comparison data, all the collectors are diluted with isopropyl alcohol to get an isopropyl alcohol content of 30 wt % (as determined by Gas Chromatography analysis) before being used in the test.

[0157] The results of calcite ore beneficiation with collectors A, B, C, D and E according to the invention (Examples 1-5) are presented in Table 1 here below:

TABLE-US-00001 TABLE 1 Dosage (ppm) Calcite purity after Calcite loss Collector (1st step/2nd step) treatment (wt %) (wt %) A 500 + 250 99.97 2.8 B 450 + 150 99.96 3.1 C 450 + 150 99.93 3.4 D 450 + 150 99.85 1.9 E 450 + 150 99.99 2.9

EXAMPLE 9: CALCIUM CARBONATE FLOTATION IN HARSH CONDITIONS

[0158] The flotation tests are performed with the laboratory flotation cell from Outotec.

[0159] 800 g of calcium carbonate ore containing 2.2 wt % of impurities (HCl insoluble) are mixed with 2.4 L of water in the plastic bowl of the flotation cell. The turbine agitation speed is set up to 1200 rpm to insure a total suspension of the ore in the cell.

[0160] Standard flotation test is run at natural pH of the pulp (pH=8.9) and tap water temperature at 19 C. When flotation tests are run in so called harsh conditions, pH of the slurry is set to 10 using calcium hydroxide and water is heated up to 30 C.

[0161] Final beneficiation is obtained in two flotation steps run in the same cell one after the other. First step lasts 8 min and second step 14 min. Before each step, the slurry is conditioned during 2 minutes with the collector before introducing the air in the cell. The air flow rate is set to 2 L.Math.min.sup.1.

[0162] During flotation experiment, froth is removed regularly with a plastic spatula and collected for analysis. The purified carbonate sample is filtrated, weighed after drying and analysed. Hydrochloric acid attack is followed by a second drying and weighing in order to measure the amount of acidic insoluble compounds (remaining silicates). The HCl attack aims at obtaining a complete dissolution of calcium carbonate by an appropriate dissolution with concentrated hydrochloric acid solution (typically 10 wt % in water). The remaining minerals that are not digested correspond to the silicates (impurities).

[0163] The froth is also rinsed and filtrated. It is then dried, weighed, submitted to HCl attack, dried and weighed again in order to deduce the amount of impurities and the calcium carbonate losses.

[0164] In order to get more significant comparison data, all the collectors are diluted with isopropyl alcohol to get an isopropyl alcohol content of 30 wt % (as determined by Gas Chromatography analysis) before being used in the test.

[0165] Results are expressed as impurities removed during treatment and loss of ore during treatment. The target is of course to get an impurity removal as high as possible with loss as low as possible but results are considered acceptable if removal is over 93.2 wt % and loss below 5 wt %.

[0166] The results of calcite ore beneficiation in normal and harsh conditions with collector B according to the invention (Examples 2) and comparative collectors FC and GC (Examples 6 and 7) are presented in Table 2 here below:

TABLE-US-00002 TABLE 2 Standard conditions Harsh conditions Impurities Calcite Impurities Calcite Dosage (ppm) removed loss removed loss Collector (1st step/2nd step) (wt %) (wt %) (wt %) (wt %) B 420 + 150 ppm 98.2 3.1 96.5 2.4 FC 500 + 250 ppm 94.3 4.0 67.6 1.4 GC 500 + 250 ppm 94.9 3.2 86.4 1.9

[0167] It has to be noticed that, in order to obtain the desired level of impurities removal in standard conditions, collectors according to prior art required an extra 25% dosage compared to the collector according to the invention. Despite this extra dosage, impurity removal drops down quickly in harsh conditions with the prior art collectors while collectors for use in the present invention maintain their activity at a more than acceptable level.

EXAMPLE 10: CATIONIC COLLECTOR FOR PHOSPHATE ORE BENEFICIATION

[0168] Phosphate ore sample containing silica impurities is treated by reverse froth flotation. Flotation test is run in the laboratory flotation cell provided by the company Outotec.

[0169] 340 g of grinded phosphate ore with particle size ranging from 30 m to 300 m are mixed with 2.5 L of water in the plastic bowl of the flotation cell. The turbine agitation speed is set up to 1500 rpm to insure a total suspension of the ore in the cell.

[0170] 0.34 g of phosphoric acid (85% grade) are added to the slurry and agitation is maintained for 3 minutes. Then, 0.17 g of a carbonate collector supplied by CECA S.A. under trade name Melioran P312 is added to the slurry and agitation is maintained for another 2 minutes before air injection starts. Air flow rate is set up to 3 L.Math.min.sup.1 and froth is collected manually during 2 minutes before air injection is stopped.

[0171] Then, 10.2 g of cationic collector B (Example 2) is added to the slurry and left under agitation during 2 minutes before air injection starts again. Froth is collected manually. Test is stopped after 4 minutes of froth collection.

[0172] The ore remaining is the cell is then filtered and dried in an oven overnight. Dried ore is weighed to determine the quantity recovered and a sample is sent to analysis in order to determine precisely the composition after treatment.

[0173] Before reverse froth flotation beneficiation, the ore (fluoro-apatite type) is containing 43 wt % of calcite and 17 wt % of quartz. P.sub.2O.sub.5 content is only 13.8 wt %. The test run only concerns quartz removal and an efficiency over 80% is considered satisfying. Complete results are nevertheless given to prove complete compatibility of the whole process and the achievement of the P.sub.2O.sub.5 enrichment around 30 wt %, that is a standard target for phosphate ore beneficiation.

[0174] The results for collector B are provided in the below Table 3.

TABLE-US-00003 TABLE 3 Silicate Calcite P.sub.2O.sub.5 content after Collector collection (wt %) collection (wt %) treatment (wt %) B 83.0 87.2 30.2

[0175] The following other collectors (Examples 11-17) have also shown good properties for ore beneficiation.

[0176] Examples 11-17 of Table 4 below are prepared following the same reaction conditions as in Example 2 and are obtained by reacting the following compounds:

TABLE-US-00004 TABLE 4 Dicarboxylic Molar Molar Fatty acid Alkoxylated fatty acid or ratio ratio Quaternising Ex. (I) amine (III) derivative (II) (I)/(III) (II)/(III) agent 11 Tallow fatty Tallow alkyl Adipic acid 0.5 0.75 MeCl acid amine + 5OE 12 Tallow fatty Coco alkyl amine + Adipic acid 0.5 0.75 MeCl acid 2OE 13 Coco fatty Tallow alkyl Sebacic acid 0.5 0.75 MeCl acid amine + 2OE 14 Tallow fatty Tallow alkyl Maleic anhydride 0.4 0.6 MeCl acid amine + 5OE 15 Palm oil Palm oil alkyl Adipic acid 0.4 0.6 MeCl fatty acid amine + 5OE 16 Tallow fatty Coco alkyl amine + Maleic anhydride 0.4 0.6 MeCl acid 2OE 17 Tallow fatty Tallow alkyl Adipic acid 0.4 0.6 MeCl acid amine + 11OE

[0177] In Table 4 above, fatty acids of formula (I) and alcoxylated fatty amine of formula (III) are described by the origin of the fatty alkyl chain. The number of ethylene oxide (OE) equivalents that have been reacted with the fatty amine are indicated after the + sign. All compounds of examples 11-17 are totally quaternised.