Abstract: A preformed yarn useful in forming fiber-reinforced carbon composite articles is disclosed which includes a core of a multiplicity of inorganic reinforcing fibers, a mixed powder provided in the interstices between the fibers and including a finely divided carbonaceous binder pitch and a finely divided coke, and a flexible sleeve formed of a thermoplastic resin and surrounding the core.

Abstract: A preformed yarn useful in forming fiber-reinforced carbon composite articles is disclosed which includes a core of a multiplicity of inorganic reinforcing fibers, a mixed powder provided in the interstices between the fibers and including a finely divided carbonaceous binder pitch and a finely divided coke, and a flexible sleeve formed of a thermoplastic resin and surrounding the core.

Abstract: A continuous process for the production of carbonaceous pitch, including heat-treating an aromatic heavy oil in a first thermal cracking zone for obtaining a first cracked product, and introducing the first cracked product into a second thermal cracking zone where it is thermally cracked by direct contact with a gaseous heat transfer medium to form distillable cracked components and a mesophase-containing pitch. The liquid phase in the second thermal cracking zone, including the mesophase-containing pitch, is discharged therefrom and separated into a mesophase-rich pitch and a matrix pitch having a low concentration of mesophase. The mesophase-rich pitch is recovered while at least a portion of the matrix pitch is recycled to the second thermal cracking zone.

Abstract: A method of preparing an carbonaceous pitch, including the steps of:subjecting a raw material oil to thermal cracking conditions while removing cracked, light hydrocarbon components to obtain a pitch product containing at least 5 weight % of mesophase and not more than 10 weight % of light hydrocarbon components with a boiling point at 60 mmHg of 300.degree. C. or less and having a softening point of between 160.degree. and 220.degree. C., the raw material oil being composed mainly of a residual oil which has a boiling point of 350.degree. C. or more and which is derived from a naphthene base petroleum crude; andremoving the mesophase from the pitch product to obtain a substantially mesophase-free carbonaceous pitch.

Abstract: A continuous process for thermally cracking a heavy hydrocarbon oil, including heat-treating the heavy hydrocarbon oil in a first thermal cracking zone for obtaining a first cracked product, and introducing the first cracked product into a second thermal cracking zone where it is thermally cracked by direct contact with a gaseous heat transfer medium to form distillable cracked components and a mesophase-containing pitch. The liquid phase in the second thermal cracking zone, including the mesophase-containing pitch, is withdrawn therefrom and separated into a mesophase-rich pitch and a matrix pitch having a low concentration of mesophase. The matrix pitch is recycled to the second thermal cracking zone. The distillable cracked components are stripped from the liquid phase in the second thermal cracking zone with the heat transfer medium, and the resulting gas phase is discharged overhead therefrom and then separated into a light fraction and a heavy fraction.

Abstract: A process for the preparation of carbon fibers, including the steps of:subjecting a raw material oil to thermal cracking conditions at a temperature of between 400.degree. to 500.degree. C. while removing cracked, light hydrocarbon components to obtain a pitch product containing at least 5 weight % of mesophase and not more than 10 weight % of light hydrocarbon components with a boiling point at 60 mmHg (absolute) of 300.degree. C. or less and having a softening point of between 140.degree. and 220.degree. C., the raw material oil having a boiling point of at least 500.degree. C. and containing at least 30 weight % of a residual oil which has a boiling point of at least 500.degree. C. and a metal content of at least 200 weight ppm and which is derived from a napthene base and/or intermediate base petroleum crude;removing the mesophase having a particle size of more than 10 .mu.

Abstract: Molten pitch is mixed and atomized in an inert gas stream having a temperature less than that of the molten pitch, cooled to the ordinary temperature and separated from the gas stream.Fine powder such as carbon, silica alumina and the like is added to at least one step of the process to improve the fluidity of the thusly obtained fine solid pitch spheres. The pitch spheres are easy to storage, handle and transport as they behave like a fluid.

Abstract: A novel reformed mesophase pitch having a mesophase content MC of between 40 and 100%, a quinoline-insoluble content QI of between 5 and 70 weight % and anisotropic domains forming a continuous phase. The reformed mesophase pitch is obtained by heat-treating a dormant mesophase pitch which comprises dormant anisotropic components which are partially hydrogenated, polycyclic polycondensed ring aromatic hydrocarbons derived from the mesophase of a mesophase pitch by hydrogenation of the mesophase and which are soluble in quinoline. The dormant mesophase pitch is optically isotropic in nature but, upon being subjected to shear forces in one direction, capable of being oriented in said direction. Preferably, the reformed mesophase pitch has a softening point SP in .degree.C. satisfying the following conditions:when 40 .ltoreq.MC<100, ##EQU1## and when MC=100, ##EQU2## The reformed mesophase pitch is useful as precursor materials for carbon fibers.

Abstract: A heavy hydrocarbon feed stock is, after being heat-treated in a first cracking zone, is introduced into a second thermal cracking zone for obtaining a thermally cracked product and a pitch product. The second cracking zone has a plurality of cracking reactors which are connected in series, through which is successively passed the treated feed stock and to each of which is supplied a gaseous heat transfer medium to maintain the liquid phase therein at a temperature sufficient for effecting the thermal cracking and to strip the resulting distillable, cracked components from the liquid phase. The thermal cracking temperature in one reactor is so controlled as to become higher than that in its adjacent upstream-side reactor. The distillable, cracked components in respective reactors are removed overhead therefrom and separated into a heavy fraction and a light fraction, while the liquid phase in the downstream-end reactor is discharged therefrom for recovery as the pitch product.

Abstract: A heavy hydrocarbon feed stock is, after being heat-treated in a first cracking zone, introduced into a second thermal cracking zone for obtaining a thermally cracked product and a pitch product. The second cracking zone has a plurality of cracking reactors which are connected in series, through which is successively passed the treated feed stock and to each of which is supplied a gaseous heat transfer medium to maintain the liquid phase therein at a temperature sufficient for effecting the thermal cracking and to strip the resulting distillable, cracked components from the liquid phase. The thermal cracking temperature in one reactor is so controlled as to become higher than that in its adjacent upstream-side reactor. The distillable, cracked components in respective reactors are removed overhead therefrom and separated into a heavy fraction and a light fraction, while the liquid phase in the downstream-end reactor is discharged therefrom for recovery as the pitch product.

Abstract: A process is disclosed for producing pitches of high quality in a high yield by subjecting selected crude oil to adiabatic thermal and steam cracking process at a temperature between 700.degree. C. and 1000.degree. C. to produce gases containing ethylene, propylene and the like and a tar pitch having an ethylene-to-acetylene ratio above 5; adjusting the pitch content of the tar pitch in the range between 20 and 80 wt % (if this content is outside this specified range); heat-treating at a temperature between about 450.degree. C. and about 550.degree. C. under a pressure between about 50 and about 150 kg/cm.sup.2 (G) for about 1 to 15 minutes, and subsequently heat-soaking at a temperature between about 350.degree. and about 450.degree. C. under a pressure between about 0.5 and about 10 kg/cm.sup.2 (G) for about 15 minutes to 10 hours.