US1364306A - Flotation of minerals - Google Patents

Description

UNITED STATES PATENT om c's.

CLEMENT L. PERKINS, 0F PITTSBURGH PENNSYLVANIA, ASSIGNOR TO METALS RECOVERY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

-FLOTA'1ION OF MINERALS.

Specification of Letters Patent.

Patented Jan. 4, 1921.

1l',36d,306. No Drawing. Application filed July 21, 1919. Serial No. 312,249.

T 0 all whom it may concern Be it known that I, CLEM NT L, PERKINS, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny, State of Pennsylvania, have invented certain new and useful Improvements in Flotation of Minerals; and I do hereby declare the following to be a full, clear, and, exact description of the invention, such as will enable others skilled in the art to which it ap-.

pertains to make and use the same.

This invention relates to the concentration of minerals, such as sulfid ores and the like,

by flotation, and is based upon the discovery I that improved results can be obtained by carrying out the flotation operation with the addition to the ore or mineral pulp of hydrazins, such as phenyl-hydrazin, etc.

Among the hydrazins and their derivatives, including the hydrazo-compounds or diaryl-hydrazins, which can thus be used, may be mentioned the following :phenylhydrazin, either in the form of the free base or in the form of its salts, such as the hydrochlorid or sulfate; naphthylhydrazin, as the free base or in the form of its salts; para tolyl hydrazin; acetic phenyl hydrazid, CH .CO.NH.NH.C H acetone phenyl-hydrazone (CH C:N.NH.C H tribromphenyl-hydrazin; hydrazo-benzene or symmetrical di-phenyl-hydrazin C H NHNH. C H etc. The hydrazins or their derivatives may be added either in the form of the free base, or' in the form of salts thereof withaCids. In referring to hydrazin compounds, therefore, I intend toinclude the simple and substituted hydrazins and their derivatives, whether in the form of the free base, or in the form of salts thereof.

The hydrazin compound which I have found of particular value, and which I therefore recommend, is phenyl-hydrazin (C H NIINIL). In using phenyl-hydrazin, it may be incorporated with the ore or mineral pulp in any suitable manner, for

example, by introducing it into the tube mill in which the ore is being ground, or by adding it directly in its liquid form to the ore pulp, or by first digestingit with water and adding the resulting product, or by mixing it with an organic liquid mixable therewith.

In general, however, it seems that the hydrazins can be more advantageously added to the pulp immediately before flotation, rather than to the grinding mill. Liquid compounds, such as phenyl hydrazin, may be added directly; others, 6. 9., in the form of.

solutions in water or in various organic solvents.

Phenyl-hydrazin, as well as the other hydrazin compounds, have a marked action as collecting gents; that is, agents which cause a very material increase in the recovery of mineral when used in connection with a suit able frothing agent. The hydrazins themselves nevertheless have a,considerable frotheither.

has been thoroughly and uniformly distributed throughout the ore or mineral pulp, the, resulting mixture'is subjected to a flotation operation, as .in an ordinary Ca1low.,

cell, or in apparatus where the air is incorporated in the ore pulp by mechanical agi- L tation.

It is of advantage in many cases to add to the ore pulp a small amount of alkali, not only when the hydrazin compound is used in the form of a salt, but also when the free base is employed. When a salt of the hydrazin is employed, the alkali may act upon I it, to a greater or less extent, to set free the free base, but the action ,of the alkali appears to be an action upon the ore pulp, or upon the mineral constituents, rather than or in addition to its action upon the salt of the hydrazin used, although I do not desire to limit myself by any theoretical explanation of what the action of the added alkali may be in promoting the flotation operation.- A similar improvement in the process has been noted both when alkali has been used with the free base, and when used with salts of the hydrazin. The. alkali may be caustic alkali, such as sodium hydrate, or an alkaline salt, such as sodium carbonate," or

even lime or calcium oXid or hydrate can be used. Varying amounts of the alkali can be added, but in many cases it 1s desirable to add suflicient to give a distinct alkaline reacalkali, evenwhen the lime was added to the" ground pulp in theJanney cell, and with tion to the orepulp. during the flotation; operation. When' sodium" hydroxid is used .with phenyl-hydrazin it appears possible to use a somewhat reduced amount of phenylhydrazin. I have also obtained excellent recoveries when lime was used as the added the consumption of about from onerfifth to called porphyry ores, such as those-of the *tically no collecting properties.

one-fourth pound of phenyl-hydrazin per ton. The limenot only hasan alkaline reaction, but it may have a beneficial effect in helping to settle the ore pulp. j 4

The amount'of the hydrazin onliydraz'i'n derivatives added may vary somewhat,- and may be as little as one-fifth or one-fourth pound per ton Off ore; (that is, calculated on the welghtv of the'ore, and not of the ore pulp); but larger amounts may, with advantage, be' used, particularly where no added frothing agent orflotation agent is used, and as much as one or one and one-half pounds 'used. i t

Thehydrazins and hydrazin derivatives have proven to be of particular value in the flotation'of copper sulfid ores having a silicious' gangue and containing their floatable per ton of ore, or even more, can be or sulfid copper in the .form of a mixture.

of chalcocite and chalcopyrite; thatis, so-

Utah Copper Company. When using phenyl and naphthyl hydrazins, the best results appear to be obtained by Ngrinding the ore with water and alkali adding the hydrazin to the groundpulp'im- -mediately before flotation. The results obtained in this Way were better than those obtained. by adding the hydrazins in the aOH) and then grinding mill.

Where the phenyl-hydrazin or other hydrazin compound or derivatives is used with other flotation agents, it will materially im prove the flotation result by its marked action as a collecting agent. The flotation agent With which the hydrazin compound is added may, therefore, with advanta be a flotation agent with markedfrothing properties, for example, pine oil, orother wood distillation oils, or 'terpineol, which has marked frothing properties, but prachydrazin is used with a frothing agent, the

valuable collecting properties of the hyh drazin Will thus be supplemented by the frothing properties of the frothingagent.

Where the hydrazin compound is miscible g with the other flotation'agent or agents with it is to be used, the agents may be which first admixed and compounded to form a composite flotation agent, and the composite agent then added to the ore pulp. .When

the hydrazin is a solid and, not readily solu b'le or miscible with the orepulp, it may be ground in the ball mill, or dissolved in a suitable ,organic solvent therefor,

,entinvention,

.drazins and When theamount of an aryl-hydrazin' 0 larlya solvent which is itselj. readi y miscible ,with the ore pulp, and the resulting solution then added to the ore pulp. If the hyd'razin is soluble in water, it maybe added in the form ofan aqueous solution.

' It is a characteristic of the process of the present invention that the frothobtained is readily broken up, while arelatively clean concentrate and high recovery can, nevertheless, be obtainedp The concentrate first articw,

obtained, for example, from'a rougher cell, l

v can, of course, be further .concentrated, and

the grade of the concentrate thereby further improved, by treatment in a cleaner cell or cells. i r

The process of the present invention, in

whlch hydrazins are employed, is somewhat 11 related to the process of my companion appllcation; Serial No. 312,248 filed of even date herewith in which azo-compounds, diazo compounds,

compounds used in the process of the presecting theresulting mixture to a flotation operation; substantially as described. 2. The method of eflecting'the con-centra tion of'minerals by flotation, which com j,prises adding to the mineral pulp a small amount ofa hydrazincompound, together with a flotation agent having marked frothing properties, m xture to a flotationoperation; substantially as described. L v

3. The method of effecting the concentration of minerals by flotation, which comprises addingto the mineral pulp a small a h drazin substance, together.

amount of with suflicient a kali to give to the ore pulp a..distinct alkaline reactlon; and subjecting the resulting mixture toa flotation tion; substantially as described.

4. The method of efi'ecting a concentradilfer frpm the azo and diazo compounds by the fact that the two nitrogen operaand the like, are ,em-

-ployed; but the hydrazins and hydrazina single bond and likewise have tion of minerals by flotation, which comprlses adding to the mineral pulp a small amount of a hydrazincompound, and sub- 1'10 and subjecting the resulting tion oflminerals by flotation, which comprises adding to the mineralpulp a small the general formula R-NH.NH (where R stands for an aryl radical) and subjecting the resulting mixture to aflotation 'operation; substantially as described.

.5. The method of effecting the concer-i .1-

the resulting" mixture to a flotation opera tion; substantially as desoriloeel.

6. The method; of. effecting the concentration of minerals by. flotation, which coinprieee adding to the mmeralpulp a small amount oil a hydrazin compound, in the r a H r i 1 .[OIIII ol a salt theieof wita an aoio, ano subyecting the resultmg mixture to a flotation operation.

7. The method of ellectmg the concentra tion of minerals by flotation, which com- 15 prises adding to the mineral pulp a small 4 l A a 4 e a A tion out minerals by fiotatwn, which eoinamount oi phenyl hydrazm, together with prises adding to the m neral pulp small aiifiment'alkah to give to the ore pulp a amount of phenyl-hytlicazin and aah eoting" distinct alkaline lBitC'iLlOll, ancl suhwctlng the resulting mixture to a flotation operation; substantially as clesei'iloeol 8. lhe method of effecting the concenttation of minerals by flotation, which oomprisee adding to the mineral pulp a small amount oat phenyl hydrazin, together with an agent having good trothing qualities, and subjecting the resulting mixture to a flotation operation; scribed,

ln testimony whereof I affix my signature.

CLEMENT L, lFERKlNS,

substantially as ole