US3078997A

US3078997A - Flotation process for concentration of phenacite and bertrandite

Info

Publication number: US3078997A
Application number: US101616A
Authority: US
Inventors: Havens Richard
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-02-24
Filing date: 1961-02-24
Publication date: 1963-02-26
Anticipated expiration: 1980-02-26

Description

United States Patent 3,078,997 FLOTATION PROCESS FOR CONCENTRATION OF PHENACITE AND BERTRANDITE Richard Havens, Salt Lake City, Utah, assignor to the United States of America as represented by the Secretary of the Interior No Drawing. Filed Feb. 24, 1961, Ser. No. 101,616

15 Claims. (Cl. 209-166) (Granted under Title 35, US. Code (1952), see. 266) The invention herein described and claimed may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of royalties thereon or therefor.

This invention relates to the beneficiation of phenacite (2BeOSiO bertrandite (4BeO-2SiO-H O), and associations thereof with the mineral beryl (3BeO A1 6Si02) from their ores.

Recently the discovery of large deposits of low grade ore containing phenacite and bertrandite, sometimes associated with beryl, has raised the possibility of these deposits being a source of beryllium. The ores contain, in addition to the beryllium minerals, quartz, calcite, manganocalci-te, fluorite, muscovite, sericite, apatite, and other associated minerals. To be useful, the beryllium minerals must be separated from the mass of gangue material by a simple and inexpensive process.

Accordingly, it is the main object of this invention to provide a simple and economical method for concentrating phenacite, bertrandite, and beryl, if present, from low grade ores, to a degree such that further processing to recover beryllium may be successfully undertaken.

It is an object of the present invention to provide a process for the recovery of larger quantities of phenacite, bertrandite, and beryl from their ores than may be recovered by presently known methods.

A further object of this invention is to provide an improved froth flotation method for the separation, concentration and recovery of phenacite, bertrandite, and beryl from ores, with the production of a material of suflicient beryllium content to be utilized by extractive metallurgical processes.

Yet another object of this invention is to provide an improved froth flotation process for the separation, concentration and recovery of phenacite, bertrandite, and beryl from ores, by the use of water soluble inorganic fluoride and polyphosphates as conditioners.

Other objects and advantages will be apparent from the rest of the disclosure.

In general, the invention comprises separation of phenacite, bertrandite, and beryl from associated minerals, such as quartz, calcite, manganocalcite, fluorite, sericite, apatite, and micas by a flotation process. Many of these minerals, under normal conditions, also tend to respond to fatty acid flotation. To increase the selectivity of the froth flotation process, depressants are added to prevent the entry of undesired minerals into the froth. I have discovered that fluoride ions, and polyphosphate ions, with or without borate ions acomplish this result. Crushed ore in the form of an aqueous pulp is treated with a water soluble fluoride, such as sodium fluoride for example, and a water soluble polyphosphate such as sodium hexameta phosphate (Calgon), or a mixture of Calgon and tetrasodium pyrophosphate, or Calgon and borax.

A small amount of flocculating agent, such as alum or aluminum sulfate, sometimes is useful in flocculating the concentrate or froth for fast removal from the flotation cell. In addition, these agents exert a minor supplemental depressant effect on fluorite and other gangue materials.

After a few minutes conditioning time, a collector oil such as oleic acid, tall oil fatty acid, fish oil fatty acids, etc., is added to the pulp. Kerosine may be added to the 3,078,997 Patented Feb. 26, 1963 collector, if desired. Then, after a short additional conditioning period, air is passed into the pulp, and the froth concentrate recovered.

The residual pulp is reconditioned with Calgon anc' fatty acid type collector and froth floated again, recovering a second concentrate which may be treated separately. or with the first recovered concentrate, or recycled to the first treatment. This process may be repeated with the second tailings, if desired.

The process is carried out at room temperature and atmospheric pressure conditions, and the conditioning time periods may vary from 1 to 15 minutes or more. Usually only several minutes are required as a maximum. As depressants, compounds supplying the fluorine ion may be the water soluble inorganic fluorides such as alkali meta fluorides. Ammonium fluoride or hydrogen fluoride may be used on pulps having little calcareous gangue. Sodiurr fluoride is generally used, however, as it is the most readily available. About 2 to 6 pounds of fluoride per ton o1 ore is added.

Alakli metal polyphosphates are employed as the source of polyphosphate ions, sodium hexametaphosphate (Cal gon) being the most readily available source- Mixture:

of tetrasodium pyrophosphate and borax may be employer either alone or admixed with Calgon, or borax and Cal gon. About 0.5 to 5 pounds per ton of ore of the phos phate conditioner is employed.

Collecting agents which may be employed in the proc ess are the fatty acids. These include, for example, 016i! acid, fish oil acids, tall oil (which comprises mixtures o rosin acids and fatty acids), linoleic acid, etc. About i pound per ton of ore is added. Kerosine may be adder to the collecting agent in an amount of from about 0.5 tr about 1.0 pound per tone of ore. The kerosine helps de press fluorite and other gangue material, as well as servin as a collector in conjunction with the fatty acid. Othe: neutral oils such as light or medium fuel oils may be sub stituted for kerosine. No special frother is required, a the fatty acid collector fulfills this function in the instan process under alkaline conditions. Use herein of alkal metal polyphosphates generally insures this, but if neces sary, soda ash or caustic soda may be employed to brin; pH to the required value, which may be within the mug of from about 7.5 to 9.4.

Although it is generally necessary to soften the wate when using fatty acids as collectors to prevent the forma tion of insoluble soaps, this is not required in the instan invention. Apparently, the polyphosphate conditione: also serves to prevent the precipitation of insoluble soaps The general method for carrying out the ore treatmen according to this invention is as follows:

Crushed ore is wet ground fine enough (passing a 65 mesh screen) to liberate the beryllium-bearing mineral from the gangue minerals. The pulp, a physical mixturl of finely ground or and water, is transferred to a mechani cally agitated laboratory flotation cell and then conditionei with 2 to 6 pounds per ton of sodium fluoride and 0.5 to pounds per ton of ore of sodium hexametaphosphat (Calgon), tetrasodium pyrophosphate and borax, Calgo: and borax, or mixtures of all three. After a few minute conditioning time, oleic acid, tall oil fatty acid, or simila collector, in an amount of 1 pound per ton of ore, is adder to the pulp with or without 0.5 to 1 pound per ton o kerosine per tone of ore, and conditioned for an additiona few minutes. The phenacite, bertrandite, and beryl, i present, then are froth floated'from the agitated pulp b admitting air to the flotation cell. This product would b designated rougher concentrate No. 1. A second roughe concentrate of lower grade then is froth floated as a sepa rate product by first reconditioning the residual pulp wit additional Calgon and fatty acid type collector such a oleic acid, fish oil fatty acids, purified paper mill fatt acids, etc., using about 0.2 to 1 pound Calgon and 0.5 pound of fatty acid per ton of original ore. This product may either be combined with the first rougher concentrate for cleaning or set aside in batch operation. In continuous plant processing, it is recycled through the roughing circuit, and enables mineral recoveries greater than those in the batch tests.

EXAMPLE 1 This example illixsrtlrates the poor results obtained when he depressants of 's invention are not employed.

A typical ore sample containing, in percent, 2 phenacite, Z calcite, 2 fluorite, sericite, 60 quartz, and 6 other minerals, and assaying 0.73 percent BeO, was wet ground lirough minus-65-mesh in a laboratory ball mill and froth loated using Na SiO and Na CO as conditioning reagents and oleic acid as the collector reagent. The 'ougher concentrate was cleaned usingv the same condiioning reagents. The cleaned concentrate assayed 1.68 iercent BeO and contained 52 percent of the beryllium n the ore. The rougher tailing from flotation contained .9 percent of the beryllium in the ore and assayed 0.22 )ercent BeO. Only low recovery of beryllium and a i001 degree of upgrading were achieved on this typical henacite ore by conventional fatty acid flotation.

The following examples give the results obtained with 'arious ore samples and modification of the process.

EXAMPLE 2 A phenacite sample from the Mt. Wheeler mine near 51y, Nevada, assayed in percent: 0.72 BeO; 17.1 CaCO ind 1.9 CaFg. Approximate mineral composition of this '6, in percent, was 2 phenacite, 60 quartz, calcite, 2 luorite, 10 sericite, and 6 other minerals. The sample of ll'e was wet ground at 50 percent solids in an iron ball mill or minutes to give a product approximately minus- LSO-mesh. Relatively hard (with reference to dissolved alts) Salt Lake City tap water containing about 200 arts per million total hardness was used throughout the est. The ground pulp was diluted to 30 percent solids vith water in a flotation cell and conditioned with sodium luoride and Calgon; oleic acid then was added as the :ollector and frother, and the phenacite floated as con- :entrate l. The residual pulp was conditioned with Saigon and then with oleic acid, and a second concen- Table I.Test Conditions and Flotation Results TEST CONDITIONS Time of Reagents, lbJton of ore treat- Treatment or product ment,

min. NaF Cal- Oleie pH gon acid )onditioning 5 4. 0 2. 0

o 3 1. 0 lonoentratc 1 (by Irothing). 1. 5 9. 4 )onditioning. 4

Do 2 5 9. 4 loneentrate 2 (by truth 3 RESULTS OF FLOTATION Weight, Assay, Distribu- Product percent BeO, tion, BeO,

percent percent )oncentrate 1 13. 7 4. 8 85. 6 loncentrate 2. 7. 6 31 3. 1 tougher tailing 78. 7 11 11.3

Calculated head 100. 0 77 100. 0

EXAMPLE 3 A composite sample prepared from six ores from varius parts of the same mine, assayed, in percent: 0.61 BeO, 0.7 CaCO 38.3 $0,, 5.0 CaF,, and 5.1 A1 0 The mineral composition of this sample was, in percent: 1 Ihenacite, 1 bertrandite, 30 quartz, 27 manganocalcite,

17 calcite, 4 fluorite, 8 micas, and 12 other minerals. The sample was ball-mill ground for 7 minutes at 50 percent solids to pass a 65-mesh screen and then pulped in a flotation cell to about 30 percent solids. The pulp was conditioned with sodium fluoride, Calgon, and tetrasodium pyrophosphate, then with kerosine and oleic acid. Concentrate was then recovered. Oleic acid was added to the residual pulp and a second concentrate (concentrate 2) then was froth floated. The kerosine helped to depress the fluorite and, with the oleic acid, to collect the beryllium minerals. The reagents used, test conditions, and results are given in Table 2.

Table 2.Test Conditions and Flotation Results TEST CONDITIONS Time 0! Reagents, lb. [ton of ore treat- Treatment or product ment,

min. NaF Calgon TSPP Oielc Keroacld sine Conditioning 9 4.0 3.0 1.0 3 6 0. 52 0. 53

Do Concentrate 1 (by nothing) 1 Conditioning- 3 Concentrate 2 (by irothlng) 1 RESULTS OF FLOTATION This example demonstrates that adjustments in the basic test conditions and reagent schedules may be made to achieve even better results than illustrated by Example 3.

The same composite ore was wet ground and pulped as in Example 3, and then froth floated in the manner there shown, using the specific test conditions listed in Table 3, with the results as tabulated.

Table 3.Test Conditions and Flotation Results TEST CONDITIONS Time 0! Reagents, lb./ton of ore treat- Treatment or product ment,

min. NaF Calgon TSPP Oleic Keroacld sine 9 4.0 2.5 0.8 l 3 1 05 0.53 Concentrate 1 (by irothing) 1.5 Conditioning 1. 5 35 27 Concentrate 2 (by irothing) 1.5

RESULTS OF FLOTATION Weight, Assay, Distribu- Product percent BeO, tion, BeO,

percent percent Concentrate 1 2. 4 '18. 1 68. 5 2.5 4.6 16.5 95.1 0.10 15.0

Calculated head 100.0 0. 63 100. 0

I Tetrasodium pyrophosphate. 3 min. after each reagent addition. 4 1.5 min. alter each reagent addition.

5 EXAMPLE 5 This sample, from the same deposit, was a composite of two ores. In percent its assay was 0.49 BeO, 30.8 CaCO 16.2 CaF, 4.8 A1 2.7 Fe, and 0.17 W0 The mineral composition of this ore, in percent, was 0.4 phenacite, 0.9 bertrandite, 26 manganocalcite, 15 calcite, 17 quartz, 14 micas, 7 feldspar, 17 fluorite, and 2.7 other minerals. The flotation sample was wet ground at 50 percent solids in av ball mill to approximately minus-65- mesh and pulped at 30 percent solids in a flotation cell. The steps of conditioning and recovery were similar to those described in Example 2.

The reagents test conditions, and test results are given in Table 4.

Table 4 .Test Conditions and Flotation Results TEST CON/DITIONS Ttimetol Reagents, lb./ton of ore rea Treatment or product ment, 1

min. NaF Calgon Borax Oleic Keroacid sine Conditioning 1 9 4. 0 3. 0 0. 1

Do I 3 1.05 0. 63 Concentrate 1 (by frothing) 1. 5 Conditloning 1.0 1

o 1. 5 35 .27 Concentrate 2 (by Irothing) 1. 5

RESULTS OF FLO'IATION Weight, Assay, Distribu- Product percent BeO, tion, BeO,

percent percent Concentrate 1 3. 4 10.9 66. 7 Concentrate 2 1. 6 3. 85 ll. 1 Rougher tailing 95. 0 13 22. 2

Calculated head 100.0 55 100.0

1 3 min. after each reaent addition. 1 1.5 min. aiter each reagent addition.

EXAMPLE 6 A second ore sample from Mt Wheeler mine near Ely, Nev., assayed, in percent, 4.7 BeQ, 4.3 CaCO 3.0 CaF 60.7 SiO and 4.2 Fe. The approximate mineral composition of this ore, in percent, was phenacite, 3 fluorite, 4.5 calcite, with the balance comprised of micas, quartz, feldspars, sulfides, and liminite. The sample of ore was ground in the presence of NaF and a sulfide collector, such as the xanthates or thiophosphates for example, for 7 minutes at 50 percent solids to approximately minus-65-mesh. It then was pulped in a flotation cell to about 30 percent solids and conditioned with Calgon and a frother, e.g. pine oil or a cresol, etc. The sulfides were then removed by froth flotation as a sulfide concentrate. The pulp remaining in the flotation cell then was conditioned with oleic acid and fuel oil and a phenacite concentrate froth floated to form a concentrate 1. A second and third concentrate (concentrates 2 and 3) also were floated with additional oleic acid and fuel oil. The three rougher concentrates l, 2 and 3 were combined and conditioned with additional Calgon, oleic acid and fuel oil and froth floated to recover a cleaner concentrate. Additional Calgon was added thereto and a recleaned concentrate I was recovered. The residual pulp was conditioned with additional oleic acid and fuel oil and a concentrate II was recovered by frothing.

The reagents used, test conditions, and results are summarized in Table 5. p

Table 5 .Test Conditions and F [oration Results gl'rnsr CONDITIONS Tiiiie oi Reagents. lb./ton of ore Treatment or treatproduet rnent.

.hnin. NaF Z-6 Pine Cal- Oleic Fuel pH oil gon acid 011 Grind 7 4.0 0.1 Conditioning 0. 04 0.75 Sulfide concen- 5 Conditioning 2 .9 .35 Concentrate 2 (by frothin z). 5 Conditioning 2 .9 Concentrate 3 (by irothing)--. 3 Cleaner conditioninz 3 .1 .25 .07 Cleaner concentra y frothing). 5 Recleaner contioninz 3 1 Concentrate I (by irothing) 4 Conditioning 3 .25 .70 Concentrate II (by trothing).-. 2

1 2 61s the trade name for a collecting agent consisting of mixed amyl xanthates.

RESULTS OF FLOTATION Weight, Assay, Distribu- Product percent BeO, tion, BeO,

percent percent Sulfide concentrate 0. 4 2. 4 0- 2 Concentrate I 8. 9 35. 2 68. 1 Concentrate II 2.9 26.5 16.5 Cleaner and recleaner tailing 8. 5 4. 4 8.1 Rougher tailing 79. 3 4 7. 1

Calculated head 100. 0 4. 6 0

EXAMPLE 7 A sample of ore from the Badger flats area in Colorado, assayed in percent, 0.5 BeO, 0.13 Li O, 72.9 SiO 3.6 Fe, and 13.0 A1 0 The mineral composition of this ore in percent was: 1 bertrandite, 0.3 beryl, 0.1 euclase, 40 quartz, 33 micas, 20 feldspar, with minor amounts of limonite, hematite, fluorite, calcite, lead and zinc carbonates, and sulfide minerals. A sampleof the ore was treated under the conditions and with reagents shown in Table 6. The ore was ground in the presence of NaF for 12 minutes at 50 percent solids in a laboratory ball mill to approximately l00-mesh and pulped in a flotation cell. It then was conditioned by adding Calgon and floated to form rougher concentrate 1. The residual pulp was conditioned by adding oleic acid and kerosine thereto, and a second concentrate (rougher concentrate 2) was floated. The two rougher concentrates were combined, conditioned with Calgon and then with oleic acid, kerosine and borax, and floated to recover concentrate I. The reagents test conditions, and results of flotation are given in Table 6.

Recycling of the cleaner tailing in a continuous plant would improve over-all beryllium recovery.

Table 6.Test Conditions and Flotation Results TEST CONDITIONS Reagents, lbJton of ore Time Treatment or product treat- NaF Cal- Oleic Kero 30- pH ment gon acid sine rax min.

Grind 12 3. 0 Conditioning.-. 0. 75 D 2 1.0 0.5 8.2 Bougher concentrate 1 (by trothtng) 3 Conditioning.. 2 5 25 0.05 Bougher concentrate 2 (by nothing) 2 Cleaner conditioning-.." 3 .5

D 3 .6 .25 .05 Concentrate I (by troth- RESULTS or FLOTATION Weight, Assay, Distribu- Product percent BeO, tion, BeO,

percent percent Cleaner concentrate 2. 63 12. 21 59. 9 Cleaner tailing..- 5. 09 l. 64 15. 6 Roughcr tailing 92. 28 14 24. 5

Calchlated head 100.0 0. 53 100.0

It will be appreciated from a study of the foregoing specification that the invention described therein is capable of various modifications and changes without departing from its essential spirit and scope.

I claim:

1. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an orc containing the same together with a sulfide mineral and gangue, which comprises: forming an aqueous pulp of said ore, removing the sulfide mineral therefrom by adding to the pulp a sulfide collector and a frother, frothing the said pulp to remove the sulfide mineral as a froth and leaving a residual pulp containing the beryllium minerals, adding to the residual pulp (1) a depressant for the gangue comprising a water soluble inorganic fluoride and an alkali metal inorganic polyphosphate; maintaining the pH of the resulting pulp at a range of from about 7.5 to

about 9.4; (2) a fatty acid type collector for the berylv lium mineral comprising a member of the class consisting of higher fatty acids, and a light neutral hydrocarbon oil together with a higher fatty acid; and then froth floating the beryllium minerals from the gangue.

2. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same together with gangue, which comprises: adding to an aqueous pulp of said ore (l) a depressant for the gangue comprising a water soluble inorganic fluoride and an alkali metal inorganic polyphosphate; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; (3) a flooculant comprising aluminum sulfate; maintaining the pH of the resulting pulp at a range of from about 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue,

3. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same, together with gangue, which comprises: adding to an aqueous pulp of said ore (l) a depressant for the gangue comprising an alkali metal fluoride and an alkali metal polyphosphate; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and

a light neutral hydrocarbon oil together with a higher fatty acid; maintaining the pH of the resulting pulp at a range of from about 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue.

4. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same, together with gangue, which comprises:

adding to an aqueous pulp of said ore (1) a depressant for the gangue comprising sodium fluoride and sodium hexametaphosphate; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; maintaining the pH of the resulting pulp at a range of from about 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue.

5. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same, together with gangue, which comprises: adding to an aqueous pulp of said ore (1) a depressant for the gangue comprising sodium fluoride and sodium 'hexametaphosphate; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; (3) a floc' culant com-prising aluminum sulfate; maintaining the pH of the resulting pulp at a range of from about 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue.

6. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same together with gangue, which comprises: adding to a pulp of said ore (1) a depressant for the 'gangue comprising sodium fluoride and sodium hexametaphosphate; (2) a collector for the beryllium mineral consisting of a higher fatty acid and kerosine; maintaining the pH of the resulting pulp ata range of from about 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue.

7. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same, together with gangue, which comprises: adding to an aqueous pulp of said ore (l) a depressant for the ganguc comprising sodium fluoride, sodium hexarnetaphosphate and tetrasodium pyrophosphate; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; maintaining the pH of the resulting pulp at a range of from 7.5 to about 9.4; and then froth floating the beryllium minerals from the gangue.

8. A process for the concentration of beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same, together with gangue, which comprises: adding to an aqueous pulp of said ore (l) a depressant for the gangue comprising sodium fluoride, sodium hexametaphosphate and borax; (2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; maintaining the pH of the resulting pulp at a range of from about 7.5 to about 9.4; and then froth floating the beryllium mineral from the gangue.

9. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same together with gangue, which comprises: adding to an aqueous pulp of said ore (1) a depressant for the gangue comprising a water soluble inorganic fluoride and an alkali metal inorganic polyphosphate;

(2) a fatty acid type collector for the beryllium mineral comprising a member of the class consisting of a higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid; maintaining the resulting pulp at a pH in the range of from about 7.5 to about 9.4; froth floating a first concentrate of the beryllium mineral from the gangue; separating the said first concentrate and gangue; reconditioning the tailings by adding to an aqueous pulp thereof (3) a gangue depressant selected from the class consisting of alkali metal inorganic polyphosphate borax and mixtures thereof, as required; and (4) a fatty acid type collector of the class consisting of higher fatty acids, and a light neutral hydrocarbon oil together with a fatty acid; maintaining the pH of the tailings pulp at a range of from about 7.5 to about 9.4; and then froth floating a second concentrate of beryllium minerals from the said tailings.

10. The method of claim 9 wherein an aluminum sulfate flocculant is added to aqueous ore pulp together with conditioners and depressants.

11. The method of claim 9 wherein the second beryllium mineral concentrate is recycled to the aqueous ore pulp in the first froth floating step.

12. A process for the concentration of a beryllium mineral selected from the class consisting of phenacite, bertrandite, beryl, and mixtures thereof from an ore containing the same together with gangue, which comprises: adding to an aqueous pulp of said ore a depressant for the gangue consisting of 2 to 6 pounds of sodium fluoride per ton of ore, 0.5 to pounds per ton of ore of a member of the class consisting of sodium hexametaphosphate, tetrasodium pyrophosphate, borax and mixtures thereof, the borax always being admixed with at least one of the other members of the class; a collector for the beryllium mineral comprising a member of the class consisting of a higher fatty acid, and a light neutral hydrocarbon oil together with a higher fatty acid, the higher fatty acid being in an amount of about 1 pound per ton of ore and the said hydrocarbon oil in an amount of from about 0.5 to about 1 pound per ton of ore; and froth floating the beryllium minerals from the gangue.

13. The method of claim 12, wherein the gangue depressant consists of about 4 pounds of sodium fluoride, and about 2 pounds of sodium hexametaphosphate, and the collector consists of about 1.0 pound of oleic acid, all the weights being in pounds per ton of ore.

14. The method of claim 12, wherein the gangue depressant consists of about 4.0 pounds of sodium fluoride, about 3 pounds of sodium hexametaphosphate, about 1.0 pound of tetrasodium pyrophosphate, and the collector consists of about 0.5 pound of oleic acid and 0.5 pound o; kerosine, all of the weights being in pounds per ton o ore.

15. The method of claim 12, wherein the gangue depressant consists of about 4.0 pounds sodium fluoride, 3.0 pounds sodium hexametaphosphate, 0.1 pound borax, and the collector consists of about 1.0 pounds of oleic acid and about 0.5 pound of kerosine, all of the weights being in pounds per ton of ore.

References Cited in the file of this patent UNITED STATES PATENTS 2,040,187 Rose May 12, 1936 2,373,305 Gieseke Oct. 7, 1942 2,385,819 Lamb Oct. 2, 1945 2,424,552 Clemmer July 29, 1947 2,666,587 Runke Jan. 19, 1954 2,797,808 Tueter July 2, 1957 OTHER REFERENCES United States Bureau of Mines RI 4040, March 1947.

Eigles et al.: Floatability of Beryl, Second U. N. International Conference on the Peaceful Uses of Atomic Energy, volume 3, 1958, pages 162-166.

Claims

3. A PROCESS FOR THE CONCENTRATION OF A BERYLLIUM MINERAL SELECTED FROM THE CLASS CONSISTING OF PHENACITE, BERTRANDITE, BERYL, AND MIXTURES THEREOF FROM AN ORE CONTAINING THE SAME, TOGETHER WITH GANGUE, WHICH COMPRISES: ADDING TO AN AQUEOUS OF SAID ORE (1) A DEPRESSANT FOR THE GANGUE COMPRISING AN ALKALI METAL FLUORIDE AND AN ALKALI METAL POLYPHOSPHATE; (2) A FATTY ACID TYPE COLLECTOR FOR THE BERYLLIUM MINERAL COMPRISING A MEMBER OF THE CLASS CONTAINING OF HIGHER FATTY ACID, AND A LIGHT NEUTRAL HYDROCARBON OIL TOGETHER WITH A HIGHER FATTY ACID; MAINTAINING THE PH OF THE RESULTING PULP AT A RANGE OF FROM ABOUT 7.5 TO ABOUT 9.4; AND THEN FROTH FLOATING THE BERYLLIUM MINERALS FROM THE GANGUE.