USRE12964E - A corpo - Google Patents

Description

E. G. ACHESON.

PROCESS OF MAKING GRAPHITE,

APPLIOATION FILED APR. 9., 1909..

Reissued June 1, 1909.

i K I I I I v flflenwr:

UNITED STATES PATENT OFFICE.

EDWARD GOODRICH ACHESON, F NIAGARA FALLS, NEW YORK, ABSIGNOR TO THE INTER- NATIONAL ACHESON GRAPHITE COMPANY, OF NIAGARA FALLS, NEW YORK, A CORPO- RATION OF NEW JERSEY.

PROCESS 0] name GBAIHITE.

No. 12,964. Specification .ofleiaeued Letters Patent. Reialued June 1,1909.

Original No. 711,001, dated October 14, 1802, Serla1-No.=40,766. Application or saline filed April 9,1900. I aerial-No. 489,086.

To all whom it may concern: I

Be it known that I, EDWARD Goomuonv AoHEsoN, of Niagara Falls in the county of Niagara and State of New York, have invented a new and useful Process of Making Graphite, of which the following is a full, clear, and exact description, reference being had to the accom anying drawings, forming part of this spec cation, in which Figure 1 shows in vertical longitudinal section a furnace adapted for the ractice of my invention. Fig. 2 is a vertica cross-section thereof on the line II II of Fig. 1.

Heretofore in accordance with the processes invented and patented by ine 'raphite has been made in electric furnaces y subjecting to the intense heat of such furnaces carbon admixed either naturally or artificially with materials capable of forming carbids. I have now discovered a process whereby carbon, either devoid of such carbidroducing material or containing it in insufiicient pro ortions or insufficiently distributed, may e converted into graphitic form. The invention is of great value, because it renders available materials which heretofore were not useful for this purpose, and it conduces eatly to the ease of manufacture and regu l rity and thorough graphitization of the product.

have discovered that a very perfect transformation of amorphous carbonmay be produced by causing metallic vapors to act upon the amorphous carbon at the high temrature which is obtainable in an electric mace and that this can be brought about by subjecting metals ormetallic compounds to heat in an electric furnace containlng the amo hous carbon, thus volatilizing the met or compoundand causing the va r thereof to permeate the mass of carbon which forms the charge of the furnace.

While various forms of amorphous carbon may be used and the carbon may be drawn from various sources and various metals and compounds capable of determining the conversion of carbon into graphite may be employed for generating the vaporsuch as iron, silicon, titanium aluminum, boron, or compounds thereof1 will describe my process with reference to amorphous carbon obtained from the distillation of petroleum-oil, known in commerce as petroleum-coke,

and with iron as the metallic agent. In an electric furnace which may be constructed, as shown in Fig. 1, with electrodes 2 2 extending into it at the ends, I place petroleum-coke, broken to such state that its particles vary in size from a powder to lumps, measuring, say, three inches or four inches in diameter and preferably in such proportion that the lumps are fully and completely embedded in the powder. Through this mixture I scatter or roughly mix oxid of iron in the proportion of, say, five pounds of iron oxid to one hundred pounds of coke. I also place in the furnace extending through the charge a conductor composed, preferably, of carbon rods or plates 3 3, which are in contact with each other and are connected with electrodes at the ends of the furnace. The entire charge ofcoke (indicated in the drawings by the reference-numeral 4) is preferably covered with an air-excluding layer of nonheatconducting material, which may be sand and powdered carbon in pro er roportion to form carbid of silicon. he urnace being thus charged an electric current is caused to pass through the carbon rods embedded in the charge mixture.

With a furnace of, say, thirty feet in length, fourteen inches in width, and eighteen inches deep a current of about two hundred volts and three hundred amperes is suitable. This current will quickly increase in volume as the result of the lessened resistance of the carbon rods and of the surrounding coke as the temperature increases.

After the operation is complete,'which is indicated by a great reduction of the resistance, and when sufficient time has elapsed for the cooling of the contents of the furnace the coverin of sand and carbon, which has been partia y converted into carbid of silicon, is removed and the coke which has been converted into soft-graphitic carbon is taken from the furnace.

During the operation of the furnace the o'xid of iron that has been scattered throughout the carbonaceous material is first reduced, the iron being brought to the metallic state, and the reduced iron is either held in the cavities and interstices of the pieces and lum s of coke or settles in a mass to the floor of t e furnace, whence as the operation continues and the temperature rises it is volawhere the carbon to be gra hitized is sufliciently conducting. The orm and construction of the furnace may be modified without departing from the rinciples of my. invention.

It is also possi 1e to vary the relative amount of the metallic element empkiyed.

rom the foregoing description those skilled in the art will be enabled to employ my invention in the gra hitization of various kinds of amorphous car on and to use in the process various kinds of metals or metallic com ilounds as the source of the vapor by whic the charge of the furnace is permeated.

I claim as my invention 1. The method herein described of making graphite, which consists in introducing into an electrical furnace a mass of carbon to be graphitized, in the form of lumps, and also introducing thereintoa volatilizable material capable of forming a carbid, and heating the same to a high tern erature, vaporizing the volatilizable material, thereby causing the vapor to permeate the charge of lumps and to graphitize the same; substantially as described.

2. The method herein described of making graphite, which consists in introducing into an electrical furnace a mass of carbon in the formof discrete lumps, and also introducing thereinto a volatilizable material capable of forming a carbid, and heating the mass to a high temperature, va orizing the said lement or compound, t iereby causing he vapor to permeate the charge of lumps to'graphitize the same; substantially as escribed.

3. The method herein described of making graphite, which consists in introducing into an electrical furnace a mass of carbon in the form of discrete lumps embedded in powdered carbon, and also introducing thereinto a volatilizable material capable of forming a carbid, and heating the mass to a high temperature sufiicient to Va orize the said element or compound an to graphitize the carbon; substantially as described.

4. The method herein described of making graphite, which consists in introducing into an electrical furnace a mass of petroleumcoke to be graphitized, and also introducing thereinto a v0 atilizable material capable of forming a carbid, and heating the same to a high temperature sufficient to vaporize the said volatilizable material and to graphitize the carbon; substantiall as described.

In testimony whereof have hereunto set my hand.

EDWARD GOODRIGH ACIIESON.

Witnesses:

W. A. SMITH,

01mm E. DUNLAP.

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