US1915788A - Treatment of highly reactive metals - Google Patents

Description

j as tion is of course objectionable.

Patented June 27, 1-933 pair-as was 7 CHAR ES HARD-Y, F PELHAM MANOR, 1\TEW YORK, Assn-non To nanny METAL? LURGICAL COMPANY, AVCOEFORATION or nnnawaan V v ,TREATME T OF HIGHLY nnnorivn METALS No Drawing.

This invention relates to the treatment of highly reactiveinetals and has for its object certain improvements in the treatmel'ltv of I highly reactive metals; The present. inven tion relates more particularly to the treat-- ment of such highlyreactivemetalsas the alkali metals, as well as to the treatedmeta'lshighly reactive metals maybe included cal-- cium, magnesium, sodium, lithium, barium, potassium and the llke. Some of these met als have been employed as deoxldizers, de-

sulphurizers anddeca'rbonizers in thetreatment of various materials; Such metals are diflicultyto store and handle because of their great afiinity for constituentstaken from the cium, for example, on continued exposure to the air gradually di'slntegrates into a pul verulent mass. This disintegration is not alone due to contact of themetalliccalcium with oxygen of the air, but results inpartby reaction with hydrogen, nitrogen, carbon,

sulfur and the like taken from the air and the humidity in the air. The calcium on ex posure to the air disintegrates into a pulverulent mass, and is no longer calc1um;-but 1s a compound of calcium,- such as calcium carbonate, calcium nitrite, calcium carbide, etc. When it is desired to employ the highly reactive metal in a solid mass, such disintegra- Even though the metal may be confined in air-tight containers, such a procedure is at best inconvenient. .Those working around the mateparticularlycontemplates a mechanically agglomerated admixture of one or more highly '56 reactive metals of the alkali metal group with atmosphere. A stick or bar'of-metallic cal-;

rial tend sooner or later carelessly to expose Application filed January22,1931."Serial m a,

one'or more other metals, such "as iron orcjopperand the like. Such agglomerates or a briquettes may bemaderelatively porousor, solid,=depending upon the pressure employed to produce them; orthe' manner in which :5

they are otherwiseprepared, r i

As a result of my further investigations along' these lines, I have determined that; the highly reactive metals may be so treated as to inhibit disintegration due to reaction on While in contact with the air, and thus keepthem as metals until they are subsequently. employed. Sticks or barsor other masses/of the highly reactive metals maybe appro;

pri'ately treated with an essentially non-reacjc5 tive substance-to offer a" suitable protective coveringor coating. 1

v ccording-to t ly reactive metal or metalsis provided with a suitable protective covering,*tl1e covering a;

being adaptedto keep the-metal or metals out of contact with air. :Iheinvention alsocontemplates the thus protectedor'covered reac' I tive metal as an article of manufacture.

WVhile it, is customaryin common practice I V i l 'to employ a single given 1 highly reactive metal for the purpose of eiiecting the'purifi.-. 1 cation of other metals, in some instances-two or more highly reactive-metals in one single. mass may be employed at the same time In at:

the practiceof: the present invention, it is therefore contemplated" that one or morehighly reactive metals'may likewise together be suitably provided with a protectivecovering or coating to avoid disintegration when exposed to air. I 7

Furthermore, the metal 'ormetals to be protected against disintegration may be putuprin various ways. Thus, the highly reactive metal may be present as a solidified mass. On the other hand, the'hig'hly reactive metal or metals may be appropriately agglomerated or briquetted with one or more other metals, not so highly reactive, such as disclosed-in my copending application, after' which the protective covering is provided on surfaces normallyexp'o'sed to the open atmosphere. y v v c When the highly reactive metal or metals is to be present as a solidified mass, the mass .0?

nepre'sentinvention, ahigh- I i vmay be puts'up'in' various ways. Thus, the

highly reactive metal may be solidified in the form of sticksor bars. Due to their great 7 affinity for oxygen, hydrogen, nitrogen, carvery small surface of calcium exposed'to' the open atmosphere. l/Vhen themolten metal-has appropriately solidified, the protective coveringor coating may be provided on the normally exposed'surface or the upper endof the cartridge form may be tight- 1y cramped or otherwise appropriately closed; 1

thus keepingthe contained calcium out of contact with air and moisture. v I I I L I I faces of the mass of highly reactive metal The highly reactive metals; may, however,

The highly reactive metal may be retained in the cartridge form, and used as such in a subsequent purification treatment opera-' tion. If, for example, copper is to be sub jected to a purificationoperation, the cartridge shell may advantageously consist 'of' copper; The loaded cartridge, containing the solidifiedreactive metal, such as calcium, may then be, subsequently immersed inimolten copper to be purifiedc It will ofcourse be apparent that any suitable metal shell may be employed in which to introduce and hold a highly reactive metal.

In order to putup the highly reactive metals in a form readily usable in commerce, other procedures may be followed: Thus,. molds may be employed that are adapted to contain a maximum amount of the molten reactive metal with a minimum exposure of that metal to the open atmosphere. In this manner, solidified spheres or cubes or the like of the highly reactive metal may be produced. These masses are then suitably pro- I vided with a protective covering or coating;

such as by dipping or immersion'in, or by spraying, a liquid of appropriate composition.v

-As indicated above, the protective covcring should consist essentially of a non-reactive substance; that is, at least non-reactive I to the metal to be protected. For example, a massofhighly-reactive metal may be provided with a coating of appropriate water glass, such as the well-known silicates.

Nitrocellulose preparations may be applied to exposed surfaces of the highly reactive metal mass. 'Certaln varnishes are appropriate'for this purpose. 'S'uitablemolten salts I may also beapplied to themass to be protected. borax solutionwiseft'ective as a protectivesagentii Paratfinmay be usedyas'" I I may bees-wax." Intact, I have found a mix ture'of paraflin 'and bees wax to be particularlyeffective. The covering or coating should be one that doestnot readlly crack and thus open small areasto lair exposure. All of these protective agents are properly brought in directcontact with exposedsun be;otherwiseprotected. Thus, a special shell like non-metallic covering may bemplaced around and about the metalmass. For this purpose, thewell known cellophane coverings may be employed; In fact, shell-like metallic coverings may housed, such, for example, as tin foil, lead foil, aluminum foilor the CHARLES HARDY.