Methods for manufacturing carbon fiber from coal
View Patent ↗Embodiments discloses herein relate to methods of processing coal. A method to process coal includes subjecting raw coal to a liquefaction process effective to form a pitch resin, subjecting the pitch resin to a variable crystallinity spinning process effective to form raw fiber, and subjecting the raw fiber to a carbonization process effective to form a low thermal conductivity carbon fiber.
1 . A method of processing coal, the method comprising:
subjecting raw coal to a liquefaction process effective to form a pitch resin;
forming a blend additive from the raw coal;
subjecting the pitch resin to a variable crystallinity spinning process effective to form raw fiber while adding the blend additive to the pitch resin, the blend additive comprising an anisotropic pitch with a degree of anisotropy between 0% and 80%;
subjecting the raw fiber to an oxygen stabilization process at a temperature of between about 200° C. and about 300° C.; and
subjecting the stabilized fiber to a carbonization process effective to form a carbon fiber.
2 . The method of claim 1 , further comprising adding an additional blend additive to the pitch resin before or during the variable crystallinity spinning process.
3 . The method of claim 2 , wherein the additional blend additive includes one or more of an isotropic pitch, an anistroptric pitch of varying degrees, or a thermoplastic blend additive.
4 . The method of claim 3 , wherein the thermoplastic blend additive includes at least one of phenolic resins or lignin.
5 . The method of claim 1 , wherein the variable crystallinity spinning process includes a melt blown solvated-spinning system.
6 . The method of claim 1 , further comprising foaming the raw fiber effective to introduce voids in the carbon fiber.
7 . The method of claim 1 , further comprising adding an oxygen-containing additive to the pitch resin before or during the variable crystallinity spinning process.
8 . The method of claim 7 , wherein the oxygen-containing additive includes an oxygen containing polymeric material.
9 . The method of claim 1 , further comprising adding one or more compounds comprising heteroatoms to the pitch resin before or during the variable crystallinity spinning process.
10 . The method of claim 9 , wherein the one or more compounds comprising heteroatoms includes oxygen or nitrogen.
11 . The method of claim 1 , further comprising processing the low thermal conductivity carbon fiber to produce a carbon fiber insulation.
12 . The method of claim 1 , wherein subjecting the raw fiber to an oxygen stabilization process includes maintaining the fiber under tension.