Process for making carbon electrode impregnating pitch from coal tar
AssigneeAristech Chemical Corporation
InventorJohn Stipanovich, Jr.
Life of this patent
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Abstract
Carbon electrode impregnating pitch is made from coal tar by centrifugation of the coal tar to remove particulates, followed by milling and distilling the remaining material.
Claims13
Method of making a coal-tar pitch suitable for impregnating a carbon form comprising (1) centrifuging a coal tar at a viscosity less than 400 Saybolt Universal Seconds to remove at least 75% of the solids therein greater than 15 microns, (2) milling the centrifuged coal tar with milling media less than 5 mm in diameter, and (3) distilling the milled tar to produce a coal-tar impregnating pitch.
Coal-tar impregnating pitch substantially free of solid particles greater than about 1 micron, said coal-tar impregnating pitch having a Quinoline Insolubles content of at least about 3 weight percent.
Dependencies are inferred from the claim text.