Starting pitches for carbon fibers

Claim 2

A starting pitch for carbon fibers, obtained by (A) mixing (1) a heavy fraction oil boiling at not lower than 200°C obtained at the time of fluidized catalytic cracking of petroleum with (2) a hydrogenated oil selected from the group consisting of (a) aromatic nucleus-hydrogenated hydrocarbons prepared from aromatic hydrocarbons of 2-10 rings by hydrogenating the nuclei thereof, (b) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C obtained at the time of steam cracking of petroleum and/or a fraction boiling at'160-650°C obtained at the time of heat treating at 370-480°C a heavy fraction oil boiling at not lower than 200°C obtained at the time of steam cracking of petroleum, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C and (c) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C produced at the time of preparing the starting pitch by heat treatment, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C, to form a mixture of the oils (1) and (2), and then (B) heat treating the thus formed oil mixture at 370-480°C under a pressure of 2-50 Kg/cm 2 *G thereby to obtain the starting pitch for carbon fibers, the starting pitch so obtained being heat treated to produce a precursor pitch which is melt spun, infusibilized, carbonized or graphitized to obtain the carbon fibers.

Claim 3

A starting pitch for carbon fibers, obtained by (A) mixing together (1) a heavy fraction oil boiling at not lower than 200°C obtained at the time of fluidized catalytic cracking of petroleum with (2) a hydrogenated oil selected from the group consisting of (a) aromatic nucleus-hydrogenated hydrocarbons prepared from aromatic hydrocarbons of 2-10 rings by hydrogenating the nuclei thereof, (b) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C obtained at the time of steam cracking of petroleum and/or a fraction boiling at 160-650°C obtained at the time of heat treating at 370-480°C a heavy fraction oil boiling at not lower than 200°C obtained at the time of steam cracking of petroleum, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C and (c) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C produced at the time of preparing the starting pitch by heat treatment, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C and (3) a heavy fraction oil boiling at not lower than 200°C obtained at the time of steam cracking of petroleum, to form a mixture of the oils (1), (2) and (3), and then (B) heat treating the thus formed oil mixture at 370-480°C under a pressure of 2-50 Kg/cm 2 ·G thereby to obtain the starting pitch for carbon fibers, the starting pitch so obtained being heat treated to produce a precursor pitch which is melt spun, infusibilized, carbonized or graphitized to obtain the carbon fibers.

Claim 4

A starting pitch for carbon fibers, obtained by (A) mixing together (1) a heavy fraction oil boiling at not lower than 200°C obtained at the time of fluidized catalytic cracking of petroleum with (2) a hydrogenated oil selected from the group consisting of (a) aromatic nucleus-hydrogenated hydrocarbons prepared from aromatic hydrocarbons of 2-10 rings by hydrogenating the nuclei thereof, (b) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C obtained at the time of steam cracking of petroleum and/or a fraction boiling at 160-650°C obtained at the time of heat treating at 370-480°C a heavy fraction oil boiling at not lower than 200°C obtained at the time of steam cracking of petroleum, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C and (c) a hydrogenated oil obtained by contacting a fraction boiling at 160-650°C produced at the time of preparing the starting pitch by heat treatment, with hydrogen in the presence of a hydrogenating catalyst to hydrogenate 10-70% of the aromatic nuclei of aromatic hydrocarbons contained in said fraction boiling at 160-650°C and (3) a heavy fraction oil boiling at not lower than 200°C obtained at the time of steam cracking of petroleum, to form a mixture of the oils (1), (2) and (3), and then (B) heat treating the thus formed oil mixture at 370-480°C under a pressure of 2-50 Kg/cm 2 ·G thereby to obtain the starting pitch for carbon fibers, the starting pitch so obtained being heat treated to produce a precursor pitch which is melt spun, infusibilized, carbonized or graphitized to obtain the carbon fibers.

Claim 5

A starting pitch for carbon fibers according I to claim 1 or 2, wherein the hydrogenated oil (2)(c) is a hydrogenated oil prepared by collecting a fraction boiling at 160-650°C at the time of fluidized catalytic cracking of petroleum and hydrogenating the thus collected fraction to effect 10-70% nuclear hydrogenation therein, a hydrogenated oil prepared by collecting a fraction boiling at 160-650°C at the time of heat treating the heavy fraction oil (1) at 370-480°C and hydrogenating the thus collected fraction to effect 10-70% nuclear hydrogenation therein or a hydrogenated oil prepared by collecting a fraction boiling at 160-650°C produced at the time of heat treating a heavy fraction oil boiling at not lower than 200°C obtained at the time of fluidized catalytic cracking of petroleum and hydrogenating the thus collected fraction to effect 10-70% nuclear hydrogenation therein.

Claim 6

A starting pitch for carbon fibers according to claim 1, wherein the heavy fraction oil (1) and the hydrogenated oil (2) are mixed together in a mixing ratio by volume of 1 : 0.1-2.

Claim 7

A starting pitch for carbon fibers according to claim 2, wherein the heavy fraction oil (3) and the heavy fraction oil (1) are mixed together in a mixing ratio by volume of 1 : 0.1-9, and at the same time the hydrogenated oil (2) is mixed with the heavy fraction oils (1) and (3) in a mixing ratio by volume of 0.1-2 between the oil (2) and the sum of the oils (1) and (3). !