US1933796A - Blending wood pitch with fatty acid pitch - Google Patents

Description

Patented Nov. 7, 1933 BLENDING woon PITCH WITH FATTY ACID PITC Louis J. Figg, Jr., Kingsport, Tenn., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New York No Drawing. Application January 15, 1932 Serial No. 586,972

2 Claims.

duce stables, viscous, homogeneous mixtures of Wood pitch with fatty acid pitch.

5 Generally speaking, wood pitch is not compatible with fatty acid pitch. When the two are mixed, the product separates into two distinct layers. Various emulsifying agents have been tried in an attempt to produce a satisfactory blended pitch, but without success. Solvents common to both pitches have also been tried, but the resultant product is usually so thin as to be useless, and furthermore, as the solvent evaporates, separation of the two component pitches takes place.

I have discovered that it is possible to produce stable, viscous, homogeneous mixtures of wood pitch with fatty acid pitch by heating together pitches having approximately the same flow point. Pitches of any desired flow point, from 35 C. to 120 C., may be used, provided that the wood pitch and the fatty acid pitch used have approximately the same flow points. For example, wocd pitch having a flow point of 98 C.

may be heated in an open vessel or closed still with fatty acid pitch having a flow point of 95 C. until complete solution is produced. I have found it possible in this manner to blend wood pitch with fatty acid pitch in any desired proportions. The wood pitch must be free from lumps, coked tar, charcoal, wood fiber, etc.

If it is desired to obtain a product of higher flow point than that of the pitches mixed, the flow point may be raised by heating the mixture to drive ofi volatile matter until the desired flow point is attained. The heating may be carried out under vacuum or at atmospheric pressure. If it is done in an open vessel, the vessel should expose as little surface of the mixture as possible. Agitation should be avoided during the blending and heating.

The following is an example of the method of carrying out my invention. Two parts by weight of stripped settled tar from hardwood distillation, having a flow point of 35 C., (measured by the ball and ring method), and one part by weight of fatty acid pitch having a flow point of 35 C. were heated together without agitation at a temperature of 150 C. until the flow point of the mixture reached 75 C. The mixture was then poured into a container and allowed to cool. Cross sections of the resultant product showed a complete mixing. Flow points taken at the top and bottom of the mix were found to be the same as the flow point of the mix as a whole.

It will be understood that the above example is merely illustrative, and that my invention is not limited to the particular materials, prcportions, temperatures or flow points mentioned in the example. The flow point of the starting materials may be any temperature from 35 C. to 120 C., and the flow point of the final product may be any temperature from 35 C. to 120 0., except that the flow point of the final product will not, of course, be lower than that of the starting materials. The temperature at which the mixture is heated may be from 150 C.

to 250 C. The proportions in which the pitches are mixed may be any desired proportions. The wood pitch may be stripped settled hardwood tar, copper still tar, pine tar, or any other wood tar obtained from the destructive distillation of wood. The fatty acid pitch may be stearin pitch, black grease obtained in the manufacture of soap, the residual tar obtained in the distillation of cotton seed oil, or any other pitch obtained from fatty acids or animal or vegetable greases.

My novel compositions of wood pitch and fatty acid pitch may be used as a substitute for pure fatty acid pitch for blending with gilsonite. The gilsonite may be added to the pitches either before or after the pitches are blended.

What I claim as my invention and desire to be secured by Letters Patent of the United States is:

1. A process of producing a stable, viscous, homogeneous mixture of a wood pitch with a fatty acid pitch, which comprises heating a wood pitch with a fatty acid pitch of approximately the same flow point.

2. A process of producing a' stable, viscous, homogeneous mixture ofa Wood pitch with a fatty acid pitch, said mixture having a flow point higher than that of the individual pitches, comprising heating a wood pitch with a fatty acid pitch of approximately the same flow point, and continuing the heating until the flow point of the product is raised.

LOUIS J. FIGG, JR.