Patented Mar. 6, 1934 1949,956

UNITED STATES PATENT OFFICE

,949,956 ORE FOTATION AND FOTATION REAGENT Ira H. Derby and Orin D. Cunningham, Indianapolis, Ind., assignors to Peter C. Reilly, Indianapolis, Ind. No Drawing Application March 2, 193, Seria No. 59,68. 4. Claims. (C. 209-166) The present invention relates to certain im cresols, xylenols, tar acids or closely related hom provements in the froth flotation process of min ologues of the same. erals by the use of nitrogenous base salts of (b) The hydrogenated phenolic compounds. certain organic thiophosphoric acid compounds (c) The aliphatic alcohols, containing from g which contain naphthalene, or analogous sub one up to five carbon atoms such as for exam - 60 Stances, as part of the molecular structure, as ple, ethyl alcohol, n-propyl alcohol, n-butyl al herein set forth. The invention embraces both cohol, n-amyl alcohol as well as isomeric alco the product and the method of making the same, hols of the same. as well as the use of the product in the froth (d) The aliphatic and aromatic mercaptols flotation of minerals. such as the ethyl, propyl, etc. mercaptols, phe- 65 More particularly our invention is based upon nyl mercaptol or closely related homologues of the discovery that materials having flotation the same. value can be prepared by a three-step reaction, Substances as specified in the above classifia in which a (preferably polynuclear) hydrocar tion may be embraced in the term "a phenol-like is bonaceous substance such as naphthalene is made substance' in that said Substances all react in a 70 to react with phosphorus pentasulfide (Or with similar or analogous manner in the present proc phosphorus and sulfur) to form a naphthalene ess, and structurally they may be regarded as thiophosphoric acid anhydride intermediate ROH (or RSH) the OH or SH group containing product which in turn is caused to react with a labile hydrogen atom. 20 phenol (or certain other substances mentioned The naphthalene thiophosphoric acid con- 75 below), to produce a naphthalene thiophosphoric pounds, for example, obtained by the reaction acid compound which in turn is combined with of the naphthalene thiophosphoric acid anhy an Organic nitrogenous base to form a compound dride compound with the compounds of the above which may be described as a nitrogenous Jase classification are excellent flotation reagents of 25 salt of a naphthalene thiophosphoric acid con themselves as disclosed in Our application Ser. 80 pound. No. 199,625, above referred to. The organic thiophosphoric acid compounds When, however, these thiophosphoric acid com that can be employed in the preparation of the pounds are combined with Organic nitrogenous flotation reagent according to the present inven bases to form nitrogenous base thiophosphoric 30 tion are completely described and specifically acid salts, a flotation reagent is obtained which, 85 claimed in application Serial No. 199,625, which on some ores, is superior to the original thiophos has issued as U. S. Patent 1,772,386, filed June phoric acid compound obtained; particularly is it 17, 1927, and dated August 5, 1930. The pres more effective on oxidized Ores. ent case, however, relates to the compounds of We give the following classification of the ss the acid as specified in said patent, or the ana nitrogenous bases that may be employed in the 90 logues thereof with the nitrogen bases hereinafter production of the nitrogenous base thiophos more fully set forth. phoric acid salts of our invention, namely: While the naphthalene thiophosphoric acid an (a) Aliphatic amines such as, for example, the hydride compound is the preferred intermediate ethyl, propyl, butyl, and amyl amines or closely 4 in the preparation of the flotation reagent of related homologues of the same. 95 the present invention, other hydrocarbonaceous (b) Aromatic amines such as, for example, Substances may be employed equally well, such aniline, methyl or ethyl aniline, dimethyl or di as, for example, the coal tar Crystalline sub stances acenaphthene, anthracene, carbazol, ethyl aniline, toluidine, alpha-naphthylamine, As phenanthrene, or mixtures of the same as they benzyl amine or closely related homologues of l, normally occur in the refining of tar, or a coal the same. 00 tar oil consisting essentially of hydrocarbona (c) Pyridine bases such as, for example, pyri ceous substances. We use the term "hydrocar dine, quinolin, or the mixed pyridine bases ob bonaceous substance' hereinafter to cover the tained from coal tar oils. so group of substances mentioned in this paragraph. Substances which are included in the foregoing As phenol equivalents to combine, for exam classification are hereinafter embraced in the 105 ple, with the naphthalene thiophosphoric acid term "an organic nitrogenous base'. Such bases anhydride compound, we give the following clas are of course capable of combining with acids, in sification of compounds: cluding the specific acids above referred to, con 5 - (a) Phenolic compounds, such as carbolic acid, taining an organic thiophosphoric acid group lo 2 1949,956 and containing one of the hydrocarbonaceous ing essentially of a hydrocarbonaceous substance, Substances above noted. the organic thiophosphoric acid anhydride com These nitrogenous base salts of an organic pounds thus obtained being equally good as the thiophosphoric acid comprising hydrocarbona Corresponding naphthalene compound in the 5 ceous substances, such as for example, naphtha preparation of the flotation reagent of our dis 80 lene, as a part of the molecular structure, possess closure. a very high selective or collecting powerfor metal The next step in our process consists in com liferous materials in froth flotation operations; bining the organic thiophosphoric acid anhydride particularly are they effective on sulfide and oxide compounds, as prepared above, as for example ores. A suitable frothing agent such as pine oil the naphthalense derivative, with various sub 85 0. ortar acids may be employed in conjunction with stances (phenol or equivalent as above specified) the above reagents, although they possess Some to form the corresponding organic thiophosphoric frothing action of themselves. acid derivatives as illustrated by the following It is not necessary that chemically pure Sub example. stances be used in the preparation of the above Fifty (50) parts of the naphthalene-thiophos 90 reagents, since unrefined products can be en phoric acid anhydride reagent as prepared above ployed with metallurgical results practically as are slowly mixed with 50 parts of anhydrous tar good as those obtained with pure chemicals. acid, the temperature, during the mixing, not ... We give the following examples, but we do being allowed to rise above 70° C. or thereabout. not restrict the invention thereto:- The reaction takes place readily and may be con 95 SO In the preparation of the flotation reagent of sidered to be complete when the mixture has our invention, the first step in the process consists become homogeneous. The product is a syrupy in the preparation of the naphthalene thiophoS liquid. The amount of tar acid used may be phoric acid anhydride intermediate as follows: varied arbitrarily so long as there is Sufficient Fifty (50) parts of pure or partially refined present for the reaction, it being preferable to 100 naphthalene and 37.9 parts of Sulfur are melted use enough in excess to leave the reaction prod together and heated to 200° C. or thereabout with uct in a liquid condition, any excess tar acid also stirring. At this temperature the sulfur and Serving as a very good frothing reagent. - naphthalene will form a homogeneous Solution. In the above preparation we do not limit our To this solution, preferably in an inert atmost selves to a reaction temperature, but may use a 105 60 phere, is then slowly added 12.1 parts of melted little higher temperature such as 125 C. to bring yellow phosphorus with stirring. The rate of about a complete combination of these substances. addition of the phosphorus may be conveniently In like manner the various substances listed governed by the temperature of the reaction mix above as phenol equivalents may be combined ture, regulating the flow of phosphorus so that with the naphthalene thiophosphoric acid an 0 said temperature does not rise above a certain hydride reagent, namely, alcohols, and aliphatic temperature limit, such as 210° C. When the and aromatic mercaptols. addition of the phosphorous is complete the reac To produce the final product of the present tion of the phosphorus and sulfur to form phos invention 80 parts, or thereabout, of the re phorus sulfide may be said to be complete. The action product from the preceding example are 15 process then consists in bringing about the re combined with about 20 parts of aniline, toluidine, action of the phosphorus sulfide thus formed alpha-naphthylamine, coal tarpyridine bases, etc. with the naphthalene by maintaining the ten at 70° C. or thereabout. The nitrogenous base is perature of the reaction mixture at 210 C., or preferably added slowly to the tar acid naph thereabout, until there is a loss of 6.5 parts, or thalene thiophosphoric acid preparation with 120 thereabout, of sulfur as hydrogen sulfide, which stirring. The reaction may be considered to be may require from one to two hours time. The complete as soon as the last of the nitrogenous product obtained is an amber colored resinous base has been added. material, liquid at 100° C. or thereabout (or it. The product produced (anilin being employed in may separate as a crystalline product) which may the proportions and under the conditions given 125 be described as a naphthalene thiophosphoric in this example) is an amber colored syrupy acid anhydride compound. liquid. When using different proportions it is Instead of starting with phosphorus and Sul possible to make semi-solid, or substantially solid phur, 43.5 parts of phosphorus pentasulfide products. The formula of the anilin compound (PSs) and 6.5 parts of sulfur may be combined produced in accordance With example may be 130 with 50 parts of naphthalene with equally good results. CE-o S o-CH Although an excess of sulfur over phosphorus CBNS-P-S-P-S-NCBs pentasulfide is not essential, we prefer to use a small excess, not limiting ourselves, however, to 135 the amount employed above, nor do we limit our selves to the above specified temperature and time. We have found it convenient to use an excess of naphthalene over that required for the reac We, of course, do not restrict the invention to 140 tion with phosphorus pentasulfide, the excess of any theoretical formula, but the above is what we naphthalene serving as a convenient solvent me believe may be the correct one. We give this dium for the naphthalene thiophosphoric acid an formula by way of illustration of one specific hydride formed. formula falling within the scope of the invention, 70 Working under substantially the same condi believing said formula to be accurate. 45 tions, the naphthalene of the above preparation The general procedure outlined in the above may be replaced with an equal weight (50 pts.) examples may be applied in chemically com or thereabout, of pure or partially refined ace bining P2S5 with any of the various classes of naphthene, carbazol, anthracene, phenanthrene compounds outlined in the early part of the or mixtures of the same or a coal tar o consist specifications to form nitrogenous base salts of 150 1,949,956 3 certain organic thiophosphoric acid compounds with a hydrocarbon as a part of the molecular as herein disclosed, these reactions taking place structure. readily at the temperatures indicated, or there 4. The froth flotation of metalliferous materials about, in the presence preferably of an exceSS while in the presence of an aniline Salt of an of the reacting organic liquid substance (or other organic thiophosphoric acid united with a hydro suitable inert organic liquids) to serve as a Sol carbon as a part of the molecular structure. vent. 5. The froth flotation of metalliferous nate In the froth flotation of ores by the use of the rials while in the presence of an aromatic amine above products as collecting agents the said prod Salt of an organic thiophosphoric acid united with 0. ucts, although possessing some frothing action, a hydrocarbon as a part of the molecular struc 85 may require the use of a suitable frothing agent ture. such as, for example, pine oil, terpineol, cresylic 6. The froth flotation of materials while in the acid or the like. The said reagents and frothing presence of a naphthylamine Salt of an organic agents may be introduced into the pulp in any thiophosphoric acid united with a hydrocarbona 5 convenient manner and at any appropriate stage ceous substance as a part of the molecular struc 90 preceding or during the flotation operation. ture. -- - -- Thus, for example, it may be mixed with the Ore . The froth flotation of materials while in pulp in a tube mill or other device in which the the presence of a pyridine base Salt of an Organic ore is being pulverized; and the amount of Said thiophosphoric acid united with a hydrocarbona reagent may be varied between wide limits de Ceous Substance as a part of the molecular struc 95 pending upon the nature of the ore under treat ture. ment. Good results are obtained in many cases 8. Froth flotation of ores while in the presence by the use of 0.1 to 0.2 pound of the reagent per of an organic nitrogenous base Salt of an organic ton of ore. thiophosphoric compound of naphthalene com 25 The pulp is then subjected to the ordinary bined with an alcohol. t 100 aeration or froth flotation operation, producing 9. Froth flotation of ores while in the presence a foam carrying the mineral from the Ore. The of an Organic nitrogenous base Salt of an organic flotation can be conducted in any type of froth thiophosphoric compound of naphthalene Com flotation apparatus and in a neutral, alkaline or bined with a phenol. 30 acid circuit, as desired. 10. Froth flotation of ores while in the presence 105 As illustrative of the practice of the invention, of an Organic nitrogenous base salt of an organic 0.15 pound per ton of ore of the toluidine salt thiophosphoric compound of naphthaliene comi of the tar acid naphthalene thiophosphoric acid bined with a tar acid. compound was employed in conjunction with the 11. A new flotation reagent comprising an or 35 froth flotation of a difficultly floatable copper ganic nitrogenous base salt of an organic thio 10 sulfide bearing ore (containing some oxidized phosphoric acid compound united with a hydro copper mineral) of the Phelps-Dodge Corpora carbon as an essential part of its composition. tion, together with a 0.1 pound of terpineol as a 12. A new flotation reagent comprising the re frothing agent and an alkaline circuit (2.0 pound action product of naphthalene thiophosphoric 40 of lime perton). A recovery of 75%, or there acid anhydride; with a Substance selected from 15 about, of the copper bearing mineral was ob the herein described group of compounds, (a) tained, together with a high grade concentrate. phenolic compounds, (b) hydrogenated phenolic The same reagent employed in conjunction with compounds, (c) aliphatic alcohols containing the flotation concentration of Utah Copper Com from 1 to 5 carbon atoms, and (d) the aliphatic pany ore, under substantially the same conditions, and aromatic mercaptols and their homologues; 120 gave a recovery of better than 90% of the copper and with an Organic nitrogenous base. bearing mineral in the form of a high grade 13. A new flotation reagent comprising the re concentrate. action product of naphthalene thiophosphoric This application is a continuation in part of acid anhydride, with tar acid; and with an or 50 our application Serial Number 96,061 filed March ganic nitrogenous base. 25 19th, 1926. 14. A process which comprises reacting with We cairn: - phosphorus and sulfur on a hydrocarbonaceous 1. A process which comprises floating ore maa Substance capable of forming a thiophosphoric terial in the presence of an organic nitrogenous acid compound of said hydrocarbonaceous Sub base salt of a hydrocarbon compound of an Or stance, reacting on the latter with a phenol-like 30 ganic thiophosphoric acid. Substance to form an organic thiophosphoric acid 2. The froth flotation of metailiferous materia Compound of Said hydrocarbonaceous Substance, while in the presence of an organic nitrogenous and reacting on the latter with an organic ni base salt of a hydrocarbon compound of an Ora trogenous base to form an Organic nitrogenous 80 ganic thiophosphoric acid. base salt of said last mentioned acid, the latter 135 3. The froth flotation of metaiferous material being capable of use as a flotation reagent. while in the presence of an organic nitrogenous RA. H. DERBY. base salt of an organic thoiphosphoric acid united ORN D. CUNNNGEAM, 65 40

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