US2222728A - Process of concentrating minerals of the class consisting of phosphate, calcite, barite, and fluorspar - Google Patents

Description

Patented Nov. 26, 1940 UNITED STATES raoonss or m rna'rn, oancrra, sraa Francis X. Tartaron, Mulberry Fla.

Phosphate Recovery Corporation: N. Y., a corporation of Delaware OF CONCENTBATING 8 CLASS CONSISTING OF PHOS- BARI'IE, AND FLUOR- MINERAL alsignor to New York,

No Drawing. Application m 28, 1931, Serial No. 156,089

23 Claiina' The present invention relates to an improved process of concentrating non-silicious minerals of the class consisting of phosphate, calcite, barite and fluorspar from ores containing them in admixture with at least some silicious matter.-

This application is a continuation of application Ser. No. 107,635, filed October 26, 1936.

According to the invention, concentration is effected by a collecting action selectively pro- 10 duced on either the desired or undesired fraction of the ore. In flotation operations, the desired fraction may in some cases be concentrated by floating it away from the undesired fraction,

while in other cases it is the undesired fraction which is caused to float, the material remaining after this separation in the latter cases constituting the concentrate because of its retention therein of the greater proportion of the desired fraction. In tabling operations, the desired fraction may in some cases be concentrated by discharging it at the side of the table, while in other cases it is the undesired fraction which is caused to be ejected at such side, the material delivered at the table end in the latter cases constituting the concentrate because of its retention therein of the greater proportion of the desired fraction.

Regardless ofthe physical type of concentration employed, the process of the present invention is one in which the collecting action selectively produced in the ore takes place on either its desired or undesired fraction.

The concentrating procedures of the invention may be applied to ores containing any number of non-silicious minerals of the class hereinbefore defined in admixture with the silicious matter. They are carried out by the use as collectors of a certain class of organic nitrogeneous compounds to be hereinafter more particularly described, which have been found to have differential collecting properties in such ores enabling them to effect a variety of separations. To the'ore to undergo treatment, is added one of these compounds in the restricted amount necessary to cause at least one but not all of the ore constituents consisting of the silicious matter and of the nonsilicious mineral or minerals of the class hereinbefore defined to be collected in preference to the rest of such constituents. Thereafter, the ore may be treated to separate its collected portion from the other by flotation, by tabling, by jigs, by up-current classifiers, or the like. The silicious matter of the ore may thus be floated away or otherwise separated from either phosphate or calcite, while either barite or fluorspar may be floated away or otherwise separated from the silicious matter, it being understood that these are general separations capable of leading to other in the case of ores containing a plurality of nonsilicious minerals of the class hereinbefore defined. For example, fluorspar may be floated away or otherwise separated from both the silicious matter and calcite. Or, both fluorspar and the silicious matter may be floated away or otherwise separated from calcite. Further to be noted is the possibility of special cases arising in practice where the separation to be efl'ectedis contrary to the normal separation. In the case of certain ores, for example, it has been found possible to float away or otherwise separate the silicious matter from barite.

Extensive researches on compounds capable of operating as collectors in ore concentration have led to the establishment of the fact-that two dis tinct portions entirely opposite to one another in characteristics are contained in such compounds 15 which cause them to achieve collection. Funda-- mentally, these portions are as follows: (1) a water-avid chemically-active polar portion; and (2) a water-repellent chemically-inactive non-polar portion. That the two portions are both essential to make a compound a collector is true regardless of the particular fraction of the ore with respect to which the compound is to exercise its collecting properties. The function of the firstmentioned portion is to cause adherence of the compound to those particles of the ore on which collection is to take place, while that of the second-mentioned portion is to cause adherence of the compound with its attached ore particles to the air at the air-water interfaces.

It is the polar portion required of collectors which accountsfor their desired selectivity of action in the ore. While this portion may be variously constituted, the non-polar portion is generally provided by a hydrocarbon group of one character or another. The two portions required should, of course, be combined to enable them to cooperate with one another in the ore, which state of combination may be expressed as one yielding a surface active ion in solution.

I have made the important discovery that collectors having preferential affinity for the desired or undesired fraction of ores containing one or more non-silicious minerals of the class hereinbefore defined in admixture with silicious matter are compounds having an amine radical as their efiective polar portion and an appropriate hydrocarbon group as their eflective non-polar portion combined with one another to yield a positively charged surface active ion in solution. More specifically stated, the basis of the invention is the discovery that these nitrogeneous cationic active compounds, in spite of their potential capacity to collect all of the specified constituents of such ores, are nevertheless capable by their use in restricted quantities of preferentially collecting one group or another of one or more of such constituents with respect to the rest, the separation obtained as a result of their dlfferential action in any case being in accordance with the concentration desired.

As in other collectors in the art, the hydrocarbon group to be used as the effective non-polar 5 portion in the collectors of the present invention should be one fulfilling their requirement of water-repellency. .As I have found, however, these collectors do not as a general rule permit the use of aromatic hydrocarbon groups for this purpose, although an exception to this rule is a particular species of compounds to be hereinafter more fully described. On the other hand, the effective nonpolar portion of the collectors of the present invention may always be formed by an aliphatic hydrocarbon radical, provided it is of such carbon content as to be characterized by water-repellency. For example, this radical may be a straight hydrocarbon chain of six or more carbon atoms, although in many cases it should preferably be one of at least eight carbon atoms.

The collectors of the present invention may exist either in the form of free amines, i. e., amines unneutralized by acids, or in the form of amine salts, i. e., amines neutralized by acids. However, only those amine salts produced from acids characterized by substantial solubility in water can be used in the process of the present invention, such acids comprising sulphuric acid, hydrochloric acid, acetic acid, etc. In general, such salts are more stable than the corresponding amines.

The amines and amine salts capable of use in the process of the present invention are com.-

pounds in which the amine radical may be in' direct or indirect chemical union with the hydrocarbon group required. Moreover, the amine radical may be a primary, secondary, tertiary, or quaternary amine radical, so that several useful hydrocarbon groups may be chemically combined 40 therewith. In fact, several amineradicals may be present, each of such radicals being directly or indirectly attached to at least one useful hydrocarbon group.

The primary mono-amines included in the col- 45 lectors of the present invention may be expressed by the general formula R.NH2, while the salts of such amines may be expressed by the general formula (R.NH2.H) nX. In each of these formulae, the symbol R has reference to a group con- 50 sisting of or containing a suitable hydrocarbon group for water-repellency, the symbol X and multiplier n in the amine salt formula respectively appertaining to the anion of an acid substantially soluble in water and to a whole number 55 equal to the valence of the acid anion X.

From the foregoing description it is apparent that the process of the present invention may be successfully carried out with many species of amine compounds. Satisfactory results have thus 6 been obtained with simple amines and amine salts in which an amine radical is directly attached to an aliphatic hydrocarbon radical, as well as with complex condensation products and their salts in which an amine radical is connected to 65 analiphatic hydrocarbon radical through an esterified or otherwise altered carboxyl group.

The simple amine compounds characterized by direct attachment of amine and hydrocarbon radicals may be prepared in accordance with 70 known chemical reactions, it being understood that they should be caused to contain an alkyl or alkylene radical of the required number of carbon atoms.

In the case of the compounds having amine and Ill-hydrocarbon radicals connected through an altered carboxyl group, a preferred method of preparation is to condense an organic acid having a straight hydrocarbon chain of higher carbon content with an aminoalcohol. As another closely related method, however, an alcohol having a straight hydrocarbon chain of higher carbon content is condensed with an aminoacid. In either of the ensuing reactions, the carboxyl group, a polar group of negative charge commonly employed in collectors for non-silicious minerals of the class hereinbefore defined, is esterified or otherwise altered with the result that its properties normally adapting it as a polar group with reference to such minerals are destroyed. That is, the carboxyl group by reason of its alteration does not in any way interfere with the function of the amine radical, which is the effective polar portion of the complex compounds produced and becomes connected to the water-repellent hydro-'- carbon radical through the altered carboxyl group. It is to be particularly noted, however, that amine soaps are coniointly produced by either of the two reactions yielding these compounds. These soaps as anionic collectors are known to have preferential affinity for non-silicious minerals of the class hereinbefore defined, because of which they ,should be removed from the reaction product where used to effect its collecting action upon silicious gangue.

It is understood that the condensation products obtained by either of the two methods above stated are free amines capable of being used as such or as salts by reaction with the proper acids.

The process of the present, invention has also been successfully carried out with resin amine compounds consisting of amines and amine salts having an amine radical combined with a resin group in which the hydrocarbon group employed as the effective non-polar portion of these compounds is contained. As before, this hydrocarbon group may consist of any aliphatic hydrocarbon radical of the required number of carbon atoms, but for this particular species of amine compounds I have also found it possible to employ any one of various cyclic hydrocarbon groups. Satisfactory results have thus been obtained with resin amine compounds containing as their effective non-polar portion such aromatic groups as naphthene and abietene nuclei. Resin amine compounds containing the phenyl nucleus as their effective non-polar portion have also proved useful in the process of the present invention.

Concerning the preparation of the resin amine compounds, if an aliphatic hydrocarbon radical isto be employedfor water-repellency, one of the starting substances may be any unsaturated straight-chain hydrocarbon of higher carbon content. Or it may be an ester of a fatty acid containing an unsaturated straight hydrocarbon chain of higher carbon content as a radical. One or more of such hydrocarbons or esters may be utilized. For example, fuel oil as a mixture of such hydrocarbons and linseed oil as a mixture of such esters have been found useful. On the other hand, if a cyclic hydrocarbon group is to be employed for water-repellency, one of the starting substances may be a hydrocarbon of the class of naphthenes, abietenes, and analogous hydrocarbons. Or it may be a substance containing one or more of such hydrocarbons in the state of chemical combination, such as naphthenic acid and abietic acid. Still another substance which may be used is one containing the phenyl nucleus, such as benzaldehyde. Regardless of the character. of the hydrocarbon group to be employed for water-repeilency, the resin amine compolmds are prepared by condensing an aromatic amine with an aldehyde or other resin-forming substance in the presence of a reactive substance capable of introducing the water-repellent hydrocarbon group desired, to which the aromatic amine during the condensation is caused to be attached with the amine radical free and capable of reaction. If desired, the condensation may also be carried out in the presence of a mineral acid as a catalyst, in which case amine salts are produced.

The collectors of the present invention may contain aromatic groups in addition to the group constituting their eii'ective non-polar portion. This is obviously true in the case of the resin amine compounds. As another example, quaternary amine compounds may be employed having an aliphatic hydrocarbon radical of suitable carbon content connected to the nitrogen atom contained in such nuclei as the pyridine ring.

It is further to be understood that the process of the present invention is not limited to the exelusive use of its amine compounds as agents.

.- For example, a mineral oil may in certain cases be advantageously employed as a coOperatlng collector.

Some of the collectors of the present invention, particularly certain aliphatic amines and their salts, exhibit the peculiarity that they opcrate best when added to thin pulps and quickly distributed therein. Therefore, a material advantage provided by the invention resides in the fact that the usual preconditioning procedures of admixing into a thick pulp are made entirely unnecessary by these particular collectors. 'In froth flotation, for example, they may be added directly to the dilute pulp in the flotation machine, together with whatever additional agents it may be desired to employ, whereupon the float may be made immediately, without preliminary agitation. It is desired to have it understood, however, that practical results in all cases may be obtained by preconditioning the ore pulp in the usual manner. In practice, of course, simple experimental tests are necessary to determine the particular method of incorporating the reagents insuring best results in each individual case.

In so far as the actual step of concentration is concerned, the process of the presentinvention may be said to be identical in mechanical characteristics to the usual processes of concentration. In flotation, regardless of the particular ore fraction floated, there is obtained the same type of flotation froth, which is removed in the usual manner in a very short time.

The process of the present invention enables excellent results to be obtained. In general, concentrates of commercial grade are obtained in a single operation, no cleaning being required.

In those cases where the collecting action takes place upon silicious gangue, it has been found that much improved concentration may be obtained by first removing part of such gangue with the view to producing a rough concentrate of the mineral values, which is thereafter subjected in known manner to appropriate negative-ion agent treatment to separate a finished concentrate by the usual collecting action upon such values. In the case of a phosphate ore, for example, an appreciable portion of the silica may first be floated away from the phosphate mineral by the use of an amine compound of the invention. Thereafter, the non-floated material as a rough concentrate of the phosphate mineral may be admixed with fatty acid soap as a negative-ion agent, as well as with the usual substances employed with such soap (1. e., mineral oil and alkali), and in this state subjected to flotation to iioat oi! a finished concentrate of the phosphate mineral. Such procedures are deemed to be an important feature oi the invention, particularly in connection with phosphate ores. Fine sand is removed by the preliminary separation and the grade of feed employed in the subsequent separation is high, which factors represent increased eiliciency oi plant operation.

In preparing the ore for treatment by the process of the present invention, it is in general desirable that it be comminuted to a particle size most suitable for eflicient operation and that it be largely deslimed, its desliming greatly minimizing the consumption of the reagents. Ordinarily, the crude ore is first subjected to a preliminary grinding operation and thereafter screened or classified to remove all particles other than those desired. The undersize may then be deslimed, and the oversize reground, deslimed, and added to the deslimed undersize; or the oversize may be reground, added to the undeslimed undersize, and the whole then deslimed.

The following examples describe certain tests which have been made in carrying the invention into eiIect, the reagent proportions in each being figured on the basis of the dry weight tonnage (2000 pounds) of the material treated.

Example 1 Deslimed phosphate feed to plant No. 4 of the Phosphate Recovery Corporation in Florida, consisting mainly of so-called bone phosphate of lime (phosphate rock) and silica, and of a particle size to pass 28-mesh, was mixed with water in a laboratory-size Fagergren flotation machine, a thin pulp of about 20% solids being produced. To this pulp through the suction pipe was added 0.97 lb. per ton of a 10% kerosene solution of octadecylamine (CiaHa'zNHz), the added amount of octadecylamine being 0.09 lb. per ton. Incident to this addition, the machine was started and a froth produced, collection of the froth requiring about one minute.

The results obtained by the above procedures are indicated in the following table, it being observed that the larger portion of the phosphate values was obtained in the non-floated material:

Percent assay Percent Product Per-cent recovery weight B P L B. P. L. Ins.

Feed 100. 40. 00 100. 0 Floated 44. 4 3. 48 3. 8 N on-floated 55. 6 70. 24 14. 52 96. 2

Example 2 Example 3 Here the proportion of the solution of octadecylamine in kerosene was the same as in Example 2, but was added in conjunction with 0.14

lb. per ton of pine oil as a irother. all other conditions remaining the same. The non-floated material contained 77.17% B. P. L., the B. P. L. recovered therein being 92.2%.

Eaiample 4 For the purpose of this example a diflerent phosphate feed was taken, namely, that to Florida plant No. 2 of the Phosphate Recovery Corporation, also largely consisting of bone phosphate of lime and silica and of a particle size to pass 28-mesh and largely deslimed, but of a lower grade in B. P. L., assaying on the average about 30% B. P. L. A sample of this feed was made into a dilute pulp in the Fagergren machine, and to it was added 0.7 lb. per ton of octadecylamine in solution with l.04 lbs-per ton of kerosene, a simultaneous addition being made of 0.14 lb. per ton of pine oil. As in the preceding examples, frothing was carried out for about one minute, no preliminary agitation preceding the float. The B. P. L. content of the non-floated material was 75.06%, the B. P. L. recovered therein being As a basis of comparison with Example 4, the

following test was carried out:

COMPARATIVE TEST 1 With a thick pulp of the same feed as in Example'4 were thoroughly admixed 1 lb. per ton of caustic soda, 1.99 lbs. per ton of fuel oil, 0.6 lb. per ton of fish acid, and 0.14 lb. per ton of a frothing agent consisting of three parts of crude rosin residue dissolved in one part of kerosene oil. The pulp was then diluted and frothed in a Minerals Separation flotation machine, the floated material being re-treated in the same machine to separate a finished concentrate. This concentrate assayed 71.04% B. P. L., the B. P. L. recovered therein being 79.4%.

Example 5 Example 6 A sample of the same feed as in Example 1 was made into a thin pulp in the Fagergren machine, to which pulp were added 0.54 lb. per ton of kerosene and 0.1 lb. per tonof heptadecylamine (CmHssNHz), the latter agent being used as a 5% solution in equal parts by volume of alcohol and benzene. Frothing was thereafter immediately carried out, the froth being collected over a period of approximately one minute. The results of this test were as follows:

. Percent assay P ercent Product Per-cent recovery weight B P L B. P. L. Ins.

Feed 100. 40. 29 100. 0 Floated 51.5 7.36 9.4 Non-floated 48. 75. 26 7. 86 90. 6

Example J .2 A'sample of the same feed as in Example 4 was Example 8 The collector in this example was heptadecylamine sulphate [(C1'zHasNI-Iz)2H2SO4], which was prepared by dissolving heptadecylamine in alcohol and neutralizing with dilute sulphuric acid, methyl orange being also added as an indicator. The precipitated sulphate was first thoroughly washed with distilled water and thereafter dissolved in a mixture of equal parts by volume of alcohol and benzene.

To a pulp of the same feed as in Example 1 were added 2.78 lbs. per ton of fuel oil and an amount of the above alcohol-benzene solution corresponding to 0.4 lb. per ton of the collector dissolved therein, the added amount of the alcohol being 3.03 lbs. per ton and that of the benzene 3.51 lbs. per ton. As before, the pulp was one of about 20% solids, but in this instance it was formed in a Minerals Separation flotation machine. Incident to-the above addition, it was frothed in such machine, the silicious gangue being separated over a period of about one minute. The water which overflowed. with the froth had a pH of 8.2.

The following table indicates the results of the test:

Percent essay ercent Product 22%; recovery 8 t B P B. P. L. 1118.

Feed 100.0 4s. 0s 100.0 Floated 33. 8 7. 64 88. 84 '5. 4 N on-il0ated 66. 2 68. 73 15. 74 94. 6

Example 9 By doubling the proportion of the alcoholbenzene solution of Example 8 (i. e., by doubling the proportions of heptadecylamine sulphate and solvents), but otherwise following the identical procedures of that example, the following results were obtained, the overflow water in this in- Comparing Examples 8 and 9, it is seen that increasing the amount of heptadecylamine sulphate raises the B. P. L. content of the nonfioated material, but lowers the B. P. L. recovery therein.

Example A sample of the same deslimed phosphate feed as in Example 1 was made into a thin pulp in a Fagergren flotation machine, to which pulp were added 1.6 lbs. per ton of dodecylamine (CizHasNHz), a liquid compound at normal temperatures, no other agent being used. Immediately after this addition, the machine was started, the froth being collected for about one With the added amount of dodecylamine of the preceding example employed in conjunction with 0.72 lb. per ton of concentrated sulphuric acid, an increased B. P. L. recovery of 87.3% was obtained in the non-floated material, but the B. P. L. assay of that material was decreased to 76.57%.

Example 12 A sample of the same feed as in Example 1 was formed with water into a thick pulp of about 70% solids. To this pulp were added, during agitation in an impeller-type mixer, 1.6 lbs. per ton of dodecylamine, agitation with this agent being continued for two minutes after its addition to the pulp. Thereafter, the pulp was transferred to a Fagergren flotation machine, where it was diluted and a float collected in the usual manner. The results were as follows:

Percent assay Percent Product 2531 recovery B. P. L. Ins.

Feed 100. 0 40. 00 lOO. 0 Floated 57: 3 16.88 24. l Non floated 42. 7 71. 04 12. 72 75. 9

Example 1 3 A 300 gram charge of deslimed minus 20-mesh phosphate ore was formed with water into a thick pulp, with which were thoroughly admixed 2 lbs. per ton of hexadecylamine hydrochloride (C1sH33NH2.HCl), added as a solution in about 10 cc. of alcohol. The pulp thus conditioned was transferred to a minerals. separation machine, where it was diluted and frothed in the usual manner. The results were as follows:

tion. Subsequent treatment of the pulp in the flotation machine yielded the following results:

P t Percent msay a si gf GICOII Product weight B. P. L. Ins. B. P. L. Ins.

Example The conditions of this test were exactly the same as in Example 14, the only difference being that the laurylamine hydrochloride was used as a warm water solution. As shown by the following table, substantially the same results were obtained as in that example:

Percent assay gsg Product Pol1mm;

- weight B. P. L. Ins B. P. L. Ins.

Feed 100. 0 29. 0 63.9 100.0 100. 0 Floatcd 66. 9 6. 7 87. 4 20. 0 91. 6 Non-floated 33. l 70. 2 16. 4 80. 0 8. 4

Example 16 The collector used was 'decylamine hydrochloride (C1oH21NI-I2.HC1). A thick pulp of the same feed as in Example 13 was conditioned with 2 lbs. per ton of this collector, dissolved in alcohol. Subsequent treatment of the pulp in the flotation machine yielded the following results:

1 Percent re- Percent assay Product Percent covety weight B. P. L. Ins. B. P. L. Ins.

Feed 100. 0 29.1 64. 0 100. 0 100. 0 Floatcd 54.9 1. 6 96.3 3. 1 82.6 Non-floated 45. 1 62. 6 24.6 96. 9 17.4

In the following two examples greatly reduced quantities of amine hydrochloride were permitted by their use in conjunction with fuel oil.

Example 17 With a thick pulp of the same feed as in Example 13 were thoroughly admixed 6 lbs. per ton of fuel oil and 0.2 lb. per ton of hexadecylamine hydrochloride, the latter agent being added as a hot water solution. Subsequent treatment of the pulp in the flotation machine yielded the following results:

Percent Percent re- Pcrmnt Percent assay recovery P P rce Percent assay covery Product weight t weight B. P. L. Ins. B. P. L. Ins. B- P- L 1115- B. P. L. Ina.

Feed 100. o 27. 3 66. 0 100. 0 100. 0 eed 100. 0 29.6 62.8 100. 0 100. 0 Flnntcd 67. 0 3. 4 93. 7 8.4 95. 2 Fl ated 63.1 8. 9 86. 0 18.9 87.0 Non-floated 33. 0 75.8 9. 7 91. c 4. s Non-floated 36. 9 65. 0 22.1 81.1 13. 0

Example 14 Example 18 Another charge of the same feed as in the preceding example was made up into a thick pulp with water, which pulp was conditioned with 1.33 lbs. per ton of laurylamine hydrochloride (C12H25NH2.HC1), added as an alcohol solu- With a thick pulp of the same feed as in Example 13 were thoroughly admixed 6 lbs. per ton of fuel oil and 0.66 lb. per ton of laurylamine hydrochloride, the latter agent being added as a warm water solution. Subsequent treatment of the pulp in the flotation machine yielded the following results: a

Percent re- Percent assay 7 Product I Pemem oovvery weight B. P. L. Ins. B. P. L. Ins.

Feed 100. 0 28. 7 64.0 100.0 Float 68.8 10. 7 86. 0 25. 6 91. 4 Non-floated 3i. 2- d8. 4 l7. 6 1i. 4 8. 6

substances as fuel oil are mixed into a pulp of phosphate in the presence of the aliphatic amines or their salts, the oil is preferentially taken up by the silica. The phosphate particles do not absorb the 011 unless an excess of both agents is used, in which case there is a tendency for both silica. and phosphate to become oiled and flocculated. Whenfuel oil is used, a much smaller quantity of amine or amine salt is used than soda and -2-lbs. per tan of hexadecylamine hydrochloride, the latter agent being added as a solution in alcohol. Subsequent treatment of the pulp in the flotation machine yielded the following results, it being observed that the silica host was very clean, containing only- 1.1% of phosphate:

Percent assay Percent re- Percent cover? Product weight B.1 .L Ins. B.P.L. Ins.

In the following three examples the collectors employed were aliphatic amine compounds containing an unsaturated hydrocarbon chain.

Example A sample of the same deslimed phosphate feed as in Example 1 was made into a thin pulp in a Fagergren flotation machine, to which pulp was added 0.1 lb. per ton of nonadecyleneamine, dissolved in a small quantity of alcohol. Frothing was thereafter immediately carried out, the froth being collected over a period of approximately one minute. The B. P. L. content of the nonfloated material was 69.53% and the B. P. L. recovery therein 92.4%.

Example 21 The same procedures as in Example 20 were repeated on a sample of the same feed, except that in this instance there was employed 0.3 lb. per ton of nonadecyleneamine sulphate, added as a 3.8% solution in equal parts by volume of alcohol and benzene. The non-floated material contained 69.73% B. P. L., the B. P. L. recovery therein being 94.0%.

Example 22 The collector was octadecenylamine (C1aHa5NHz) the unsaturated analogue of octadecylamine and It is to be particularly noted that when sucha liquid at normal temperatures. The procedures and feed were again the same as in Example 20, but here 0.18 lb. per ton of this collector was added to the pulp in the machine, no other agent being employed. The B. P. L. content of the non-floated material was 67.23% and theB. P. L. recovery therein 93.3%.

By the following example the possible use in the process of the present invention of complex condensation products having amine and hydrocarbon radicals connected through an altered carboxyl groupis shown.

Example 23 1 One part by weight of commercial triethanolamine was refluxed with three parts by weight of U. S. P. oleic acid for eight hours. To remove any oleic acid combined as soap, the reaction product was thoroughly washed with absolute alcohol containing concentrated hydrochloric acid. The material thus obtained was a solution containing one or more complex amine compounds probably'in the form of hydrochloric acid salt, the following test being carried out with this solution:

1000 grams, dry weight, of the same deslimed phosphate feed as in Example 4 were admixed with water into a pulp of about 70% solids. This pulp was agitated for three minutes in an impeller-type mixer with 3 cc. of the above solution. The pulp was then transferred to a minerals separation flotation machine, where it was diluted and a froth collected for about one min- The following two examples are illustrative of resin amine compounds in which the effective non-polar portion is constituted by an aliphatic hydrocarbon radical.

Example 24 To a mixture of 10.! g. of orthotoluidine and 8 g. of linseed oil were added a mixture of 10 g. of 40% formaldehyde and 4 ccof hydrochloric acid. A violent reaction took place, liberating heat. The material was cooled, liquid poured off, and the reaction product dried on a porous tile plate. This product, probably a mixture of resin amine compounds, was dissolved in butanol, the resulting solution being used in the following test:

with a thick pulp of the same phosphate feed as in Example 1 was thoroughly admixed an amount of the butanol solution corresponding to 20 lbs. per ton of the material dissolved therein. The pulp was then diluted and a silica float separated.

The following results were obtained:

Example 25 With 10.7 g. of orthotoluidine were admixed 5 g. of fuel oil, to which mixture were added 10 g. of 40% formaldehyde admixed with 4 cc. of

ceding example, the same feed and the same quantity of collector being employed.

The results of this test were as follows:

Percent recovery 13. P.

Percent Percent asSayL Product weight B P The following four examples are illustrative of resin amine compounds containing an aromatic hydrocarbon nucleus as their effective non-polar portion.

Example 26 To a mixture of 10.7 g. of orthotoluidine and l g. of practical naphthenic acid were added 15 g. of 40% formaldehyde admixed with 4 cc. of concentrated hydrochloric acid. The material was heated for ten minutes and thereafter, while hot, dissolved in butanol in the proportion of 1 g. to 5 cc. of solvent, the resulting solution being used as follows:

A thick pulp of the same feed as in Example 1 was conditioned with 10.8 lbs. per ton of kerosene and an amount of the butanol solution corresponding to 20 lbs. per ton of the material dissolved therein. The pulp was then diluted and a silica float separated.

The following results were obtained:

Percent assay Percent Product 225$: recovery B. P L. Ins.

Example 27 With 10.7 g. of orthotoluidine were mixed 11 as Nelioresin, to which mixture were added 15 g. of 40% formaldehyde admixed with 4 cc. of concentrated hydrochloric acid. The material was heated for five minutes and thereafter, while hot, dissolved in butanol in the proportion of ,1 g. to 5 cc. of solvent, the resulting solution being used as follows:

With a thick pulp of the same feed as in Example 1 were thoroughly admixed 18 lbs. per ton of kerosene and an amount of the butanol solution corresponding to 8 lbs. per ton of the material dissolved therein. The pulp was then diluted and a silica float separated.

'The results were as follows:

Percent assay Percent Product xg fi recovery B. P. L Ins. L

Example 28 Here retene, a hydrocarbon similar in constitution to abietenes, was used to produce the water-repellent hydrocarbon group.

To 10.7 g. of orthotoluidine admixed with 15 g. of retene were added 15 g. of formaldehyde admixed with 4 cc. of concentrated hydrochloric acid. Heating was carried out for about thirteen minutes, the resulting material being used as a 25% solution in butanol in the following test:

A thick pulp of the same feed as in Example 1 was conditioned with 18 lbs. per ton of kerosene and an amount of the butanol solution corresponding to 6.4 lbs. per ton of the material dissolved therein. The pulp was then diluted and a silica; float separated.

The results were as follows:

Percent assay Percent recovery B. P. L.

Product B. P. L. Ins.

Floated N on-floatcd 64. 7

Example 29 A mixture of 11 g. of benzaldehyde, 10.7 g. of orthotoluidine, 15 g. of formaldehyde, and 4 cc. of concentrated hydrochloric acid was heated for 10 minutes, the maximum temperature attained being 101 C. The resulting material was dissolved in butanol so as to produce a 21.8% solution, the following test being carried out with that solution:

To a thick pulp of the same feed as in Example 1 were added, during agitation in an impellertype mixer, 3.6 lbs. per ton of kerosene, 7.36 lbs. per ton of concentrated sulphuric acid, and an amount of the butanol solution corresponding to 8.72 lbs. per ton of the material dissolved therein. This addition required about one minute, subsequent to which agitation was continued for two more minutes. The pulp was then transferred to a minerals separation flotation machine, where it was diluted and a silica float separated for about one minute. Upon removal of the non-floated material (constituting the finished concentrate), the floated material was retreated in the machine, without further use of reagents. The non-floated material obtained by this second operation constituted a middling and .is indicated as such in the following table:

Percent assay Percent weight B. P. L.

Percent recovery Ins B. P. L.

Product Feed .1. Refioated M iridli'ng N (in-floated Example 30 usual manner. it contained any solids. were as follows:

the froth being removed as long as The results of the test silica float separated, the following results being obtained:

6 i P t Percent assay igs;

ercen t Percent assay gaggl q weight Product :3 5 0000. Ins. C800! Ins.

c000. Ins. OaCOa Ins.

1r"... "2 as 08 10 gal lg ig 2- gg-g Non-floated. 00.5 89.7 1.0 85.9 0.00

Non-WIIIIIIIII 1 '1 aa'c 8.0 91.0 0015 From Examples 30 to 34 inclusive, it is appar- Example 31 ent that silica may be eflectively floated away I from calcite with only a very small amount of A thick pulp of the same limestone sands as in the preceding example, was conditioned with 0.1 lb. per ton of laurylamine hydrochloride, dissolved in a small quantity of alcohol. It was then diluted in the minerals separation machine, its treatment therein yielding the following resuits:

Percent Percent assay 25 PM I Percent weight 0000; Ins. CaOO; Ins.

Example 32 The conditions of this test were the same asin the preceding example, except that the added quantity of laurylamine hydrochloride was increased to 0.133 lb. per ton. Also, upon removal of the non-floated material, the floated material was again subjected to treatment in the machine, 4 without further addition of reagent, the nonfloated material obtained by this last operation being indicated as a middling in the following table:

P t Percent assay m eroen Product weight 011001 Ins. CaCO: Ins.

' Feed 100. 0 0s. 1 n4 100.0 100.0 Reflected--- l0. 4 14. 65 79. 4 4.1 68. 7 Middling 19. 4 66. 6 33. 0 l6. 0 28. 6 Non-floated 01.2 89.7 1.0 79. 0 2.7

55 Example 33 Employing the same procedures as in Example 31*, but with the added amount of laurylamine hydrochloride further increased to 0.2 lb. per ton,

A thick pulp of the same limestone sands as before was conditioned with 0.33 lb. per ton of decylamine hydrochloride, dissolved in a small 7 quantity of alcohol. It was then diluted and a amine hydrochloride, practically all of the silica being removed in Examples 32 and 33. Here again, with increasing amount of reagent, the grade of concentrate increases and the recovery decreases. It has been found, however, that both the silica and the calcite will float if too much reagent is used.

Example 35 Analysis Product 3$ Ins. C000; MgO O; FeCO; Fe1Oi+Al:

Feed 100.0 23.0 67.9 5.12 2.31 0.67 Fated 37.2 58.0 34.0 3.60 1.63 1.37 Non-floated 02.8 2.0 88.0 0.03 2.71 0.25

Distribution Product 35 Ins. 0800] M100, reco. Fe1 a+AhO Infloat 91.3 18.6 20.2 20.4 76.1 In no nfloat 5.7 81.4 73.8 73.6 23.9

From the latter tables it is observed that all carbonates concentrated together in the nonfloated material, while the oxides of iron and aluminum were in large part floated with the silica (insoluble).

Example 36 A sample of deslimed barite ore from Sweetwater, Tennessee, was made up with water into a thick pulp of about 70% solids, which pulp was conditioned for about fifteen seconds with 1.28 lbs. per ton of octadecenylamine and. 0.14 lb. per ton of pine oil. The pulp was then transferred to a minerals separation flotation machine, where after dilution concentrated sulphuric acid was added to it in the amount of 7.2 lbs. per ton. Thereafter, frothing was carried out in the usual manner, the addition of acidbeing found to assist in depressing both silica and iron oxide. The results of this test were as follows:

bythisoperaflon watmwhereupontheu intheiormotathickpulpwith p r ton cl laurylanune hydrochloride. conditionedresidues werethen dilutedand intheusual'mannerintheiiotaticnma- .thematerialfloated middling. -'1heremltsoithis-testwereasiollows:

, the pulp was diluted 1| I u I u a I. w u w u a u 2...; 6 m :5... R a a uuuw a mm mfi s mms Mm W mme m msmtfih m a a as. w as u m m mmmm was mums? m m was m rm mm w m m we?" m .m m a shaman MW e m w aLma wm smmm M waLnuam 1 m w due. m m fl m. s 1 a m mm msm m e M MMMMM e sw m News mm w m am im mm m mn m n mmmumm mfiaflmm mfi mm was T m.. M. m w mwmn s k mwu m wwmwmm mmmuwm m i am mmm m mmmfism mm fimm ew mmm smmm mmemmm m mafia sw m i ca m Wh t u i m mm m m mm mm m m mmmtm m N w Ma mmmmmm mummmmwmd w mmmmmmsm mama volume) and then with were 0.37! lb. The irothed chine stituting a second barite The lol- I Percent MY" Percent slay Here, the

11sec. m s10- Percent asmy Ba804 m0. 510: M

so on so 14 90 p sums?" Another sanpleoi thesamebariteore was madeupwithwaterinahgermnmachineinto athmpulpoiflottsoliutowhichwlbwu baingmsdeoidlilhpertonotpineoil. l'rothlng was thereaiter immediately carried out. no u eonditioningperiodpueeedingtheflost.

lowingtableshowstheresultsoithetest 1s 96. so.

Emmple 38 Still another sample 01 the same barite ore was m as non 27.98 man 1:.25

Example 39 with the pulp in a diluted state in a minerals separation flotation machine, 72 lbs. per ton of 3 concentrated sulphuric acid were added thereto, this addition of acid being followed by the usual flotation treatment in that machine.

flnished concentrate of barite, a further addition 35 of 1.8 lbs. per ton of the same acid being made the test are shown in the following table, wherein the non-floated materials obtained by the two cleaning operations are indicated as middlings:

Product In this test a diflerent barite ore was employed with the result that the silica was floated away from the barite, the silica and 'barite of the ore being each badly stained with brown oxide of iron, which probably accounted for the activation A minus 65-mesh sample of the ore was deslimed. losing 40% of its weight, and then formed into a thick pulp with water. This pulp was conditioned with an alcoholic solution of laurylamine hydrochloride, the ratio of the hydrochloride to the ore being 0.35 lb. per ton. There-- alter, the pulp was transferred to a minerals separation flotation machine, where it was diluted FM" and irothed in the usual manner, a rougher silica float being removed. This float was twice re treated in the machine. without additional reprocessed by admixing'it in the form of a thick pulp with 1.6 lbs. per ton of octadecylamine as a a 50% solution in warmed kerosene, also with 0.14 'lb. per ton oi pine oil. the conditioning period being about fliteen seconds. As in Example 36, u

material floated was twice re-treated to yield a prior to the second retreatment. The results of of the silica or the depression of the barite.

, Example 42 v Still another sample of the same deslimed fluorsp'ar ore, in the form of a thick pulp, was conditioned for about fliteen seconds with 0.32

agent, the residue from the first retreatment be-' ing added to the residue from the flrst flotation 1o operation. These two retreatments yielded a flnal silica float, a flrst barite middling being obtalned as the residue from the second retreatment.

The aiorestated combined residues were washed lb. of octadecenylamine and 0.14 lb. 01

twice with hot hydrochloric acid (30% by both per ton. Thereafter andfrothed in the flotation machine in the usual .manner,- a rougher fluorspar float being obtained which was once retreated to produce a flnal fluorspar float anda middling. The 101- l lowing table shows the results of the test:

J Percent essay Pomnt Product Puma? recovery weight OaFs 100. 85. 36 I 0. B4 3- 18 100. 0 Final flOBt... 83. 7 95. 81 l. 61 1. a 93. 9 Middling 7. l 43. 02 39. 14 14. 74 3. 6 R68. (1st flotation)- 9- 2 Z). 02 65. 24 7. 98 2.

In each of the following two examples, the procedures were such as to cause both silica and fluorspar to float away from calcite.

Example 43 g A. sample of Hillside Fluorspar Company's Slime Pond Tailing" was sized on a 35-mesh screen, the oversize was ground to pass through the same screen and added to the undersize, and the whole was then deslimed. To a thick pulp of the deslimed material were added, during agitation in an impeller-type mixer, 1.08 lbs. per ton of octadecylamine as a 50% solution in warmed kerosene, and 0.14 lb. per ton of pine oil, a twominute period of agitation following said addition. The pulp was then diluted and frothed in a minerals separation flotation machine, a rougher float of fluorspar and silica being .removed over a period of about one minute. Upon removal of the residue, this float was three times re-treated in the machine, without further use of reagents, each of these cleaning operations yielding a middling. The results of I the test are indicated in the following table, it being observed 40 that a relatively high grade calcite product was obtained as the residue from the flrst flotation l 55 Another sample of the same fluorspar-calcite ore as in Example 43 was processed in the same way, except that 1.31 lbs. per ton of octadecylamine acetate and 0.14 lb. per ton of pine oil were substituted for the reagents of that example. Also, the rougher fluorspar-silica concentrate was four times re-treated in the machine, the results in this instance being as follows:

' Percent assay P ercent Product Percent recovery weight 08F Feed (deslimed) 100. 0 42. 11 40. 34 16.48 100.0 0 56.3 67.79 11.08 20.08 90.6 70 4th middling... a. 5 23.12 51.721 23. 90 1. 9 3rd middling--- 4. 3 18. 32 58. 28 22. 26 1. 9 2nd middling 6. 3 14. 09 64. 85 20. 03 2. 1 1st middling 9. 4 8. 18 77. 53 13. l. 8 Res. (1st flotation). 20. 2 3. 35 91. 06 4. 33 1. 7

75 In each of the following two examples, a conaaaavas centration of calcium phosphate was effected with exceptional efllciency by combining the usual process of floating that mineral by agents including fatty acid, soap with -a preliminary flotation of silica in accordance with this invention, the results attained in each instance surpassing anything-that has hitherto been possible by that process alone.

Example 45 A sample of the same deslimed phosphate feed as in Example 1 was made into a thin pulp of about solids in a Fagergren flotation machine, to which pulp was added 0.15 lb. per ton of nonadecyleneamine sulphate, dissolved in equal parts by volume of alcohol and benzene. Thereafter, without preliminary agitation, a sand float was separated for about one minute. The non-floated material obtained in this manner was used as the feed to the following flotation operation:

Dewatering of the non-floated material was carried out to a thick pulp of about 70% solids. To this pulp were added, during agitation in an impeller-type mixer, 0.8 lb. of caustic soda, 4.39 lbs. of fuel 011, 1.06 lbs. of flsh acid, and 0.14 lb. of the kerosene-rosin solution described in comparative test 1, all per ton of the original feed employed in the preliminary operation of removing sand. Agitation with these agents was continued for two minutes following their addition, which required about one minute. The

' pulp thus-conditioned was transferred to a minerals separation flotation machine, where it was diluted and a phosphate float separated for about one minute, the material remaining constituting a. tailing. Upon removal of this tailing, the material floated was re-treated in the same machine for another one-minute period, yielding a finished concentrate and a middling, this cleaning being' carried out without further addition of reagents.

The results of this test are indicated in the To a thin pulp of the same phosphate feed as in Example 1, formed in aFagergren flotation machine, was added 0.09 lb. per ton of octadecylamine as a 10% solution in kerosene, simultaneously with 0.14 lb. per ton of pine oil. Incident to these additions, the machine was started and a sand float separated. The nonfloated material thus obtained was dewatered to a thick pulp, with which were admixed 0.5 lb."

of caustic soda, 2.5 lbs. of fuel oil, 0.5 lb. of fish acid, and 0.07 lb. of the kerosene-rosin solution previously described, all per ton of the original feed. The conditioned pulp was then diluted and frothed in the usual manner in a minerals separation machine, the collected froth being again treated in the same machine to separate As a basis of comparison with Examples 45 and 46, the following two tests were carried out:

Comrmrrvn Tier 2 A thick pulp of the same feed as in Example 1 was conditioned with 0.5 lb. per ton of caustic soda, 4.45 lbs. per ton of fuel 011, 0.47 lb. per ton of oleic acid, and 0.14 lb. per ton of the kerosenerosin solution already described. Thereafter, it was treated in the usual manner in a minerals separation flotation machine, the rougher concentrate thus obtained being re-treated in the same machine to separate a finished concentrate. This concentrate assayed 80.18% B. P. L.. but the B. P. L. recovery was only 85.2%.

(Joirrm'nvn Team 3 The conditions of this test were the same as those of the preceding test, except that the added amount of oleic acid was increased to 1.18 lbs. per ton. The B. P. L. recovery in the finished concentrate was, 94.1%, but the B. P. L. assay was only 76.67%.

The following two examples appertain to the use in the process of the present invention of quaternary amine compounds in which the water-repellent hydrobarbon group is connected to the nitrogen atom contained in an aromatic nucleus.

Fa'ample 47 A one to one mixture of cetyl and oleyl alcohols, known commercially as Stenol," was esterlfied with chloroacetic acid to form cetyl and stearyl chl'oroacetate. To 33.3 g. of this mixture were added 15.8 g. of pyridine, heating of the resulting material being thereafter carried out for fifteen minutes. This material began to darken as soon as the boiling point of pyridine was approached, considerable foaming also taking place. Upon cooling, the reaction product, containing both cetyl and stearyl pyridinium chloride acetate, was washed with alcohol and ether, whereupon it was dissolved in an amount of alcohol sufilcient to produce a 6% solution, the following test being carried out with that solution:

A sample of the same feed as in Example 1 was made up with water into a thick pulp of about 70% solids. To this pulp was added, during agitation in an impeller-type mixer, an amount of the alcohol solution corresponding to 2 lbs. per ton of the compounds dissolved therein. This addition required about one minute, subsequent to which agitation was continued for two more minutes. The pulp was then transferred to a minerals separation flotation machine, where it was diluted and a silica fioat separated. A voluminous froth was produced, requiring from four to five minutes to collect.

The results 01 the test were as follows:

The conditions of this test were identical to those of Example 47, except that the mixture of quaternary amine compounds was used as a 35% solution and in the increased amount of 12 lbs.

per ton, the results in this instance being as follows:

Percent Percent Percent we are Feed 100. 0 41. 70 100. 0 Pleated... 51.6 5. 73 6. 5 Non-floated 48. 4 80. 59 93. 5

The applicability of the process of the present invention to tabling is shown by the following example:

Example 49 A sample of the same deslimed phosphate feed as in Example 1 wasformed with water into a thin pulp of about 20% solids. To this pulp in a mixer was added 0.4 lb. per ton of octadecylamine in solutionwith 3.6 lbs. per ton of kerosene, agitation with these agents being carried out for a short period of about 15 seconds to insure their proper distribution in the pulp. Thereafter, the pulp was fed to laboratory-size Wilfley table with the following results:

Percent assay P ercent Product" Pe'mnt recove y weight B P B. P. L. ins.

Feed 100.0 42. 44 100.0 Discharge side 46. 7 8.88 9.8 Dischargeend 53. 3 71.84 12.10 90. 2

None of the detailed procedures described in the foregoing examples should be interpreted as limiting the invention, these procedures being capable of being-modified in many ways without departing from the spirit of the invention.

What is claimed is:

1. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fluorspar in admixture with silicious matter, an organic nitrogeneous cationic active collector having a positively charged surface active ion, said collector being used in restricted amount causing it to collect at leastone but not all of the specified constituents of the ore in preference to'the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected fraction of the ore and poorer in the other fraction.

2. In a process of concentration, the step of adding to an aqueous pulp of an ore containing at least one non-silicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicicus matter, an organic nitrogeneous cationic active collector having a positively charged surface active ion, said coltocollect at least one but not all of the specified constituents of the ore in preference to the .rest of such constituents; and the further step of subjecting the pulp to a flotation operation to float off a material richer in the selectively collected fraction-of the ore and poorer in the other fraction.

3. In a process of concentration, the step of adding to an aqueous pulp of an ore containing at least onenon-silicious mineral of'the class consisting-o'f phosphate, calcite, bariteand fiuorspar in'admixtu're with silicious matter, an organic nitrogeneous cationic active collector having a positively 'char'gedsurface active ion, said collector being used in restricted amount causing it to collect at least one but not all of the specified constituents of the ore in preference to the rest of such constitunts; and the further step of subjecting the pulp to a tabling operation to cause a material richer in the selectively collected fraction of the ore and poorer in the other fraction tobe. ejected at the table side.

4. In a process of concentration, the step of adding, to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, a compound selected from the class consisting of free amines containing a ater-repellent aliphatic hydrocarbon radical andthe salts of said amines with acids substantially soluble in water, said compound being used'inr'estricted amount causing it to collect at leastfone 'butnot all of the specified constituconstituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected fraction of the ore and poorer in the other fraction.

5. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, an agent selected from the class consisting of compounds of the general formulae R.NH2 an'd (R.NI-I2.H) 11X, in which two formulae the symbol R has reference to a group consisting of a straight-chain aliphatic hydrocarbon radical of at least eight carbon atoms, the symbol X and multiplier n of the second formula respectively appertaining to the anion of an acid substantially soluble in water and to a whole number equal to the valence of the acid anion X, said agent being used in restricted amount causing it to collect at least one but not all of the specified constituents of the ore in preference to the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected fraction of the ore and poorer in the other fraction. v

, 6. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral' of the, class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, a compound selected from the class consisting of the sulphuric acid, hydrochloric acid, and acetic acid salts of aliphatic primary mono-amines having the amine radical directly attached to afstraight-chain aliphatic hydrocarbon radical of at least eight carbon atoms, said compound being used in restricted amount causing it to collect at least one but not e'nts' of the ore in preference tothe rest of such a material richer in the selectively collected fraction of the ore and poorer in the other fraction.

7. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, an agent obtainable by condensing a fatty acid of higher carbon content with an aminoalcohol and subsequent treatment of the reaction product to remove the fatty .acid combined as soap, said agent being used in restricted amount causing it to collect at least one but. not all of the specified constituents of the ore in preference to the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected fraction tr the ore and poorer in the other frac-- tion.

8. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, a compound selected from the class consisting of free amines having an amine radical connected to a resin group containing a water-repellent hydrocarbon group and the salts of said amines with acids substantially soluble in water, said compound being used in restricted amountcausing it to collect at least one but not all of the specified constituents of the ore in preference to the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected fraction of the ore and poorer in the other fraction.

9. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, an agent obtainable by condensing an aromatic amine with a resin-forming substance in the presence of a reactive substance capable of introducing a water-repellent hydrocarbon group, said agent being used in restricted amount causing it to collect at least one but not all of the specified constituents of the ore in preference to the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected firaction of the ore and poorer in the other fract on.

10. In a process of concentration, the step of adding to an ore containing at least one nonsilicious mineral of the class consisting of phosphate, calcite, barite and fiuorspar in admixture with silicious matter, an agent obtainable by condensing an aromatic amine with an aldehyde in the presence of a reactive substance capable of introducing a water-repellent hydrocarbon group and in the presence of a mineral acid as a catalyst, said agent being used in restricted amount causing it to collect at least one but not all of the specified constituents of the ore in preference to the rest of such constituents; and the further step of separating in an aqueous pulp a material richer in the selectively collected {raction of the ore and poorer in the other fracion.

11. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to such an ore an organic nitrogeneous cationic active collector having a positively charged surface active ion, said collector being used in restricted amount causing it to collect silicious matter in preference to phosphate values; separating in an aqueous pulp a material richer in silicious matter and poorer in phosphate values; and collecting the remaining material as the concentrate.

12. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to an aqueous pulp of such an ore an organic nitrogeneous cationic active collector having a positively charged surface active ion, said collector being used in restricted amount causing it to collect silicious matter in preference to phosphate values; subjecting the pulp to a flotation operation to float off a material richer'in silicious matter and poorer in phosphate values; and collecting the non-floated material as the concentrate.

iii." The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to such an ore a collector selected from the class consisting of free amines containing a water-repellent aliphatic hydrocarbon radical and the salts of said amines with acids substantially soluble in water, said collector being used in restricted amount causing it to collect silicious matterin preference to phosphate values; separating in an aqueous pulp a material richer in silicious matter and poorer in phosphate values; and collecting the remaining material as the concentrate. a

14. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to such an ore a compound selected from the class consisting of free aliphatic primary mono-amines having the amine radical directly attached to a straight-chain aliphatic hydrocarbon radical of at least eight carbon atoms and the salts of said amines with acids substantially soluble in water, said compound being used in restricted amount causing it to collect silicious matter in preference to phosphate values; separating in an aqueous pulp a material relatively rich in siliciousmatter and relatively poor in phosphate values; and collecting the remaining material as the concentrate.

15. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises 'adding to an ore an organic nitrogeneous cationic active collector having a positively charged surface active ion, said collector being used in restricted amount causing it to collect silicious matter in preference to phosphate values; separating in an aqueous pulp a material rich in silicious matter; subjecting the remaining material to negative-ion agent treatment for preferential collection of phosphate values; and separating in an aqueous pulp a. material rich in phosphate values as the concentrate.

16. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to such an ore a compound selected from the class consisting of free aliphatic primary mono-amines having the amine radical directly attached to a straight-chain aliphatic hydrocarbon radical of at least eight carbon atoms and the salts of said amines with acids substantially soluble in water, said compound being used in restricted amount causing it to collect silicious matter in preference to phosphate values; separating in an aqueous pulp a material rich in silcious matter; treating the remaining material with agents including fatty acid soap for preferential collection of phosphate values; and separating in an aqueous pulp a 'material rich in phosphate values as the concentrate. 17. The process of concentrating calcite from theclass consisting of free amines containing a water-repellent aliphatic hydrocarbon radical and the salts of said amines with acids substantially soluble in water, said compound being used in restricted amount causing it to collect silicious matter in preference to calcite; separating in an aqueous pulp a material richer in silicious matter and poorer in calcite; and collecting the remaining material as the concentrate.

19. The process of concentrating barite from ores containing silicious matter, which comprises adding to such an ore an organic nitrogeneous cationic active collector having a positively charged surface active ion, said collector being used in restricted amount causing it to collect barite in preference to silicious matter and separating in an aqueous pulp a material richer in barite and poorer in silicious matter as the concentrate.

20. The process of concentrating barite from ores containing silicious matter, which comprises adding to such an ore a compound selected from the class consisting of free amines containing a water-repellent aliphatic hydrocarbon radical and the salts of said amines with acids substantially soluble in water, said compound being used in restricted amount causing it to collect barite in preference to silicious matter; and separating in an aqueous pulp a material richer in barite and poorer in silicious matter as the concentrate.

21. The process of concentrating phosphate minerals from ores containing silicious matter, which comprises adding to such an ore an agent selected from the class consisting of free amines obtainable by condensing an organic acid having a straight hydrocarbon chain of higher carbon content with an aminoalcohol and the salts of said amines with acids substantially soluble in water, said agent being used in restricted amount causing it to collect silicious matter in preference to phosphate values; separating in an aqueous pulp a material richer in silicious matter and poorer in phosphate values;and collecting the remaining material as the concentrate.

22. A process of concentrating calcite from ores containing silicious matter, which comprises adding to such an ore an agent selected from the class consisting of free amines obtainable condensingan organic acid having a straight hydrocarbon chain of higher carbon content with an aminoalcohol and the salts of said amines with acids substantially soluble in water, said agent being used in restricted amount causing it to collect silicious matter in preference to calcite; separating in an aqueouspulp a material richer in silicious matter and -poorer in calcite; and collecting the remaining material as the concentrate. a

23. A process of concentrating calcite from ores containing silicious and aluminiferous minerals, which comprises adding to such an ore an agent selectedirom the class consisting of free amines obtainable by condensing an organic :acid having a straight hydrocarbon chain of higher carbon content with an aminoalcohol and the salts of said amines with acids substantially soluble in water, said agent being used in restricted amount causing it to collect silicious and FRANCIS x. TARTARON.