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INDUSTRIAL A N D ENGINEERING CHEMISTRY
Vol. 23, No. 11
JACOB F. SCHOELLKOPF MEDAL A W A R D For achievement declared to constitute a major advance in engineer, and the successful business administrator. The value science and t o embody the spirit of research in industry Frank of his inventions is attested by the remarkable commercial J. Tone, president of The Carborundum Company, Pu’iagara development which has been built upon them. Falls, N. Y., was chosen as the first recipient of the Jacob F. The idea of founding the medal originated with Robert J. Schoellkopf Medal of the Western New York Section of the Moore in 1929, when he was vice chairman of the Western New AMERICAN CHEMICAL SOCIETY.The medal was formally pre- York Section of the SOCIETY Mr. Moore, now associated sented on September 2 , 1931, a t the public meeting in connection with the General Bakelite Corporation, Bloomfield, N. J., enwith the eighty-second convention of the AMERICAN CHEMICAL listed the interest of Jacob F. Schoellkopf, who agreed to create SOCIETY in Buffalo N. Y., by Moses Gomberg, of the Cniversity a trust fund for the purpose. The Jacob F. Schoellkopf medal is of Michigan, President of the SOCIETY. to be awarded annually by the Western New York Section Outstanding contributions of Mr. Tone (as cited by the jury for outstanding work in industrial chemistry. The face of the of award) include his work, with the late F. A . J. Fitzgerald, on medal carries a likeness of J . F. Schoellkopf against a background the production and commercial properties of silicon carbide, the of Niagara Falls, with whose power development Mr. Schoellkopf production of pure metallic silicon, and the industrial applica- has long been intimately associated. The reverse of the medal tion of electrochemistry. Nearly one hundred patents have been bears a wreath and the inscription: “Awarded by Western granted to Mr. Tone, who possesses t o an unusual degree the New York Section, American Chemical Society, t o Frank J. rare combination of the qualities of the pure scientist, the plant Tone.”
High-Temperature Products of Silicon Frank J. Tone THECARBORUNDUM
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N 1891 when Acheson, with his plumber’s-pot furnace, produced the first silicon carbide crystals on the end of a carbon rod by the aid of a few amperes of electric current, he opened the door to vistas wider than he knew. This experimental furnace is popularly called the cradle of the artificial abrasive industry, but it was more than that. To it as a beginning may be traced the numerous progeny of which artificial graphite and siloxicon are the oldest children, followed later by recrystallized silicon carbide, silicon metal, silicon monoxide, siliconized silicon carbide, fibrous silicon oxycarbide, fused mullite, and other silicon compounds and allied products. ’ In reviewing the history of this large family of high-temperature products of silicon, what jumps to view above all else is Mother Nature’s readiness to disclose her secrets to the scientific worker if only he will play the role of apt pupil. The discoveries of the reaction products of silicon and carbon a t high temperature almost always were due to some furnace disorder, some accident or failure of operating control. Take, for instance, the first child of the silicon carbide furnace-graphite. Toward the end of the silicon carbide furnace run, portions of the product frequently became overheated. Down in the high-temperature zone next to the core, silicon carbide dissociated, silicon was vaporized, and the carbon remained as graphite. Once a piece of one of the amorphous carbon electrodes broke away from the terminal of the furnace, fell into the core, and was converted to graphite. In these two happenings Nature disclosed to the alert mind of Acheson the way to produce artificial graphite and graphitized electrodes. They have now become the basis of a great industry. It soon came about that, when something went wrong with the furnace and it showed symptoms of indigestion, we were a t once on the lookout for a new product. We came to welcome some of these manifestations of the ‘‘cussedness of inanimate objects” and to console ourselves after the fashion of Browning’s Rabbi Ben Ezra, reflecting with him:
NIACARA FALLS,N. Y .
Then welcome each rebuff That turns earth’s smoothness rough; Each sting that bids nor sit nor stand but go. Be our joys three parts pain; Strive, and hold cheap the strain.
In the following remarks I shall describe some of the vagaries of the silicon carbide furnace which proved such a stimulus in our research. Silicon Metal
A good example is the genesis of massive silicon metal. The normal working of the silicon carbide furnace is a quiet orderly affair, but it was not invariably so. Occasionally the core became displaced, owing to the uneven settling of the charge, and this caused high-resistance regions or hot spots to develop, giving rise to excessive temperatures. The current by-passed the conducting core and found a new path through the floor of the furnace. When the furnace was unloaded, it showed a very poor output of silicon carbide but a high output of fused bricks and moIten pavement, interspersed with large nodules and masses of a dark metallic product of bluish silver luster, which was soon identified as elemental crystalline silicon, now commercially called silicon metal. It was one of my first interests to devise a new furnace structure to keep the current in the straight and narrow path, to follow up the new product and determine how it was formed, and to develop a cheap commercial process for producing silicon metal as a main product. Up t o this time silicon was available only in the form of powder or small crystals and, a t a price of $100.00 an ounce ( 7 ) ,it found little use outside the laboratory. As stated in a paper delivered before this SOCIETY by F. S. Hyde in 1899, the preferred method of making silicon was to reduce silica with magnesium powder, fuse the reduction product with cryolite and aluminum to form an alloy of aluminum and silicon, and then treat with hydrochloric acid, leaving silicon in finely divided bright spangles.
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