Héroult, Paul Louis Toussaint

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Héroult, Paul Louis Toussaint

(b. Thury-Harcourt, Normandy, France, 10 April 1863; d. Cannes, France, May 1914)

metallurgy.

Héroult was born in the St. Bénin quarter of the small town of Thury-Harcourt, which is on the Orne River. His father, a tanner, later left Normandy in order to become director of a more important tannery in Gentilly, near Paris.

In 1882 Héroult was admitted to the École des Mines at Paris. He studied under Henry Le Chatelier, who communicated to him his great interest in aluminum; Le Chatelier had studied under Henri Sainte-Claire Deville, who, by acquiring the knowledge needed for the electrolytic preparation of aluminum, had established the aluminum industry.

Sketches of electrolysis tanks have been found in Héroult’s course notebooks which plainly indicate the young inventor’s projects. Released from military service in 1884, he went to work in the family tannery in Gentilly, where he carried out his first experiments on aluminum.

In April 1886, when he was twenty-three years old, Héroult registered his patent for the electrolysis of melted cryolite at approximately 1000° C, in a crucible lined with carbon and serving as a cathode; the melted aluminum accumulates at the bottom of the crucible. An anode of pure carbon is plunged into the bath and is burned by the oxygen liberated at its surface. This is exactly the procedure followed today.

Héroult proved to be an equally great inventor in another area of metallurgy: he is considered the creator of the method used for preparing steels in the electric furnace. In 1907 he patented a furnace in which the arc was produced between the heated scrap iron and a graphite electrode. There are many of these furnaces throughout the world, all of the Héroult type. The first direct-arc electric furnace installed in the United States was a Héroult furnace.