Abstract: Manufacture of isotropic coke by first selecting as feed material tar from low temperature carbonization with a hydrogen content above 5.5%, a carbon content less than 88% and a softening point above 60.degree. C., filtering the tar to remove solid particles, and heating the filtrate to a temperature between about 900.degree. C. and 1300.degree. C. to form an isotropic coke.

Abstract: Continuous production of coke by pyrolysis of a hydrocarbon mixture containing petroleum tar, coal tar pitch or pyrolysis tars in which the hyrocarbon mixture and recycled condensate is heated in a preheater at a rate to increase the mesophase content of the mixture up to 30 to 60%; the preheated mixture is then heated in a coking zone at a rate to form a raw coke having a mesophase content of 70 to 100%; continuously removing the raw coke from the coking zone and heating it in a calciner. The coke produced is more uniform and the process more efficient.

Abstract: Manufacture of coal-tar pitch coke with a predetermined degree of anisotropy of the linear thermal expansion coefficients and thermal volume expansion coefficient by adding primary resin and secondary resin to produce a pitch mixture having primary resin content and secondary resin content to cause on coking of the mixture production of coke having the desired properties of degree of anisotropy and thermal volume expansion coefficient. By the addition of the resins, production of a coal-tar pitch coke with a volume expansion coefficient between approximately 3 .times. 10.sup.-6 and 18 .times. 10.sup.-6 an anisotropy degree of approximately 1.1 to 2.0 may be obtained.

Abstract: Manufacture of pitch coke with needle-like structure by mixing pyrolysis oil condensate formed in the process with a coal-tar pitch having a softening point between 70.degree. and 150.degree. C, filtering the mixture at a temperature 100.degree. to 200.degree. C above the softening point, heating the filtrate to a temperature between 450.degree. and 525.degree. C in a tubular heater and coking the heated filtrate in a coking drum, passing volatile pyrolysis products from the drum to a fractionating column for separation of pyrolysis oil condensate from non-condensible gas.