US2268615A - Process for obtaining deoxidized copper - Google Patents

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, Jan. 6, 1942. R. PERRIN 2,268,615

PROCESS FOR OBTAINING DEOXIDIZED COPPER Filed March 14, 1938 Fave/a Z01,

Patented Jan. @1942 2,288,615 PROCESS FOR. OBTAINING DEOXIDIZED COPPER Iten Perrin, Paris, France, assignor to Societe dElectrochimie, dElectrometallurgic et dos Acleries Electriques dUgine,

corporation of France Application March 14,1938, Serial No. 195,841

' In France March 16, 1937 1 Claim. (on. -76) In metallurgy, in order to decompose certain harmful compounds which the metallic baths contain, reactions are often produced between these metallic baths and solid substances, but these reactions vary according to the nature of the solid substance and the metallic bath present.

Paris, France, a

sible in the processes previously known to utilize all the reacting energy of the solid material in relation to the compounds contained in the bath upon which it should react. To sum up A solid substance placed in the presence of a v metallic bath-may behave in various ways.

(a) If it is fusible under the conditions of the operation it will fuse as soon as it is brought into contact with the bath, and there will be in fact a reaction between the liquids.

(b) If it is soluble in the bath it will dissolve therein (like for example carbon in the metallurgy of steel) and it will then act in the liquid state on the element or elements of the metallic bath upon which it should react. (c) This substance finally may remain solid in the presence of a metallic bath while reacting on certain compounds contained in the bath; this is for example the case of carbon brought into the presence of oxidized copper.

If in fact the case of oxidized copper is specially considered it is to be noted that it was already known to treat copper by materials containing carbon with the object of obtaining a far-reaching deoxidation but the reactions utiobtaining chemical equilibrium between the solid material and the compounds to be attacked thereby is long and difllcult.

With the object of arriving rapidly and economically at this equilibrium by renewing with an accelerated frequency the surface of the contact between the bath of metal and the solid reacting material possessing the properties recalled above, I have proposed according to the lized are generally slow and must be eflfected in furnaces.

Thus it has been proposed to improve the contact between copper and the carboniferous substance to bury the carbon in the body of the copper by filling completely with-pieces of coke the electric furnace in which the operation is efiected, but the operation is not rapid, the renewal of the contact betweenthe copper and the coke is not suiiicient and it is indispensable in practice to apply external. heat. Moreover it is necessary to employ considerable quantities of coke which produces an increased consumption of electrical energy.

The disadvantages cited above are suppressed by utilizing the process according to the invention which gives the possibility of efiecting farreaching and rapid reactions without necessarily employing external heat between a metallic bath and a solid substance of density less than the metal, not dissolving therein and not melting at the temperature of the reaction.

The diiiiculties which have been met with up to the present in similar treatments arise precisely from the fact that the solid materials utilized have a density less than that of the metal, are insoiubletherein and do not melt at the temperature of the operation. It is imp s- .present invention to subject the reacting ele- By this means the rapidity of the reactions is such that no application of external heat is necessary. It is important however to explain how these successive intermixings should beeffected for the success of the operation. If it is supposed that one of the chambers of the apparatus contains molten metal upon which the solid reacting-substance has been dropped and that the metal is poured slowly from this chamber into the other chamber, the solid reacting material having a density much less than that of the metal remains at the surface of the bath facilitated by the eddies which are produced from the shock of the molten metal against the walls of the chamber into which it is poured.

It is important in all cases that the pouring of the metal with the solid reacting material should be sufliciently strong for there to be penetration of the pieces of solid reacting material into the body of the metal, which condition is the more diflicult to produce the greater the difference between the density of the reacting material and that of the metal.

If the reaction between the solid reacting material and the metal gives rise to the production of a solid or liquid substance of low volatility it is important to pour as rapidly as possible. It is likewise suitable in this case that the solid substance should be introduced preferably into the apparatus in a sufllciently divided form for example in the form of little pieces, grains, or even perhaps of powder.

If on the contrary the action of the solid substance on the metal gives rise to a gaseous or very volatile substance precautions should be taken so that the reaction is not active enough to lead to an explosion or even to expulsion of metal out of the apparatus. Besides the fact that the apparatus should be suitably open to permit the outlet of gases as they are formed two means may be provided for adjusting the activity of the reaction.

(1) The movement of the apparatus may be slowed down. It must however remain sufliciently rapid for there to be penetration of the solid reacting material into the body of the molten metal, which condition is essential for rapid reaction.

(2) The solid reacting material may be introduced periodically in regulated proportion (at .each .period oi movement for example) or even in a less divided form. It is of importance not to use too fine powder which may be entrained partially by the gases which are evolved.

The adjustment will be effected for each particular treatment by previous tests.

The process of the invention is capable of being applied in advantageous condition in an pparatus of thy type represented by way of ample schematically in the accompanying drawing.

The apparatus comprises two chambers I and 2 relatively deep connected to one another and communicating with a medial aperture 3 open to the atmosphere. These two chambers are constituted by a metallic casing- 4 provided with a refractory lining 5. The whole is mounted on a shaft 6 capable of turning in support bearings I and receives a rapid alternating oscillatory movement by means of a suitable driving mechanism of known type which isnot shown. This movement brings turn by turn each of the cham-- hers I or 2 into a position respectively high or low and with an inclination such that its contents are projected energetically and from the greatest height which the construction of the apparatus permits into the other chamber. This effect may be facilitated by imparting at first a speed so great that centrifugal :iorce maintains or tends to maintain charge towards the bottom of the receptacle which contains it, and then rapidly decreasing when the bottom or the receptacle is about to reach or reaches the top of its path. Q

The process and the apparatus described may be applied particularly to the deoxidation of oxidized copper by utilizing carbon as solid reacting material.

The following is an example of such an-application.

Into an apparatus such as that shown in the drawing 1 metric ton of very oxidized molten copper was introduced (bran grain copper containing 1.1% of oxygen). At the same time 5 kgs. of charcoal previously heated were added and several oscillations were eflected. At each pouring an energetic intermixing and a very active ebullition are produced; Continuing the oscillations of the apparatus 800. gms. or charcoal will be added every fourth oscillation. At the end of a few minutes the oxygen content had fallen to 0.02%. The copper remained molten.

What I claim is:

A process for quickly and regularly obtaining I copper very low in oxygen from oxidized copper by means of successive simultaneous and violent pourings of fluid copper and charcoal, characterized in that the total quota of charcoal necessary for the deoxidizing operation is introduced in successive portions in the form of charcoal pieces, the succession of the introduction of the said portions being regulated so as to correspond to the exhaustion of the action of the preceding portion.

RENE PERRIN.

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