A method of making a carbon fiber comprising esterification of a lignin precursor with an acid, acid anhydride, or acyl halide, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a carbon residue selected from the group of coal based raw material, petroleum based raw material and combinations thereof, thereby forming a fiber precursor mixture; and spinning the fiber precursor mixture into a fiber. A method of making a carbon fiber comprising esterification of a lignin with an acid derivative, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a pitch, thereby forming a fiber precursor mixture; and spinning the fiber precursor mixture into a fiber. A method of making a carbon fiber comprising lowering the T.sub.g of a lignin material, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a carbon residue, thereby forming a fiber precursor mixture and spinning the fiber precursor mixture into a fiber.

A method of making a carbon fiber comprising esterification of a lignin precursor with an acid, acid anhydride, or acyl halide, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a carbon residue selected from the group of coal based raw material, petroleum based raw material and combinations thereof, thereby forming a fiber precursor mixture; and spinning the fiber precursor mixture into a fiber. A method of making a carbon fiber comprising esterification of a lignin with an acid derivative, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a pitch, thereby forming a fiber precursor mixture; and spinning the fiber precursor mixture into a fiber. A method of making a carbon fiber comprising lowering the T.sub.g of a lignin material, thereby forming a reduced T.sub.g lignin. Mixing the reduced T.sub.g lignin with a carbon residue, thereby forming a fiber precursor mixture and spinning the fiber precursor mixture into a fiber.

Carbon fibre precursors for use in the formation of carbon fibre materials. The carbon fibre precursors comprise fibres of polymeric material which have a coating layer thereon, the coating layer comprising a material susceptible to dielectric heating, for example carbon nanotubes. The carbon fibre precursors may be suitable for forming into carbon fibres using a dielectric heating step, despite the fibres of polymeric material not being susceptible to dielectric heating, without adversely affecting the structure and physical properties of the main body of the carbon fibre so formed. A method of preparing a carbon fibre precursor for a carbon fibre formation process and a method forming a carbon fibre are also disclosed.

Carbon fibre precursors for use in the formation of carbon fibre materials. The carbon fibre precursors comprise fibres of polymeric material which have a coating layer thereon, the coating layer comprising a material susceptible to dielectric heating, for example carbon nanotubes. The carbon fibre precursors may be suitable for forming into carbon fibres using a dielectric heating step, despite the fibres of polymeric material not being susceptible to dielectric heating, without adversely affecting the structure and physical properties of the main body of the carbon fibre so formed. A method of preparing a carbon fibre precursor for a carbon fibre formation process and a method forming a carbon fibre are also disclosed.

A problem to be solved by the present invention is to provide a new form of adsorbent suitable for a motor vehicle canister. An activated carbon fiber sheet satisfies one or two or more of conditions for indices, such as a specific surface area, a pore volume of pores having a given pore diameter, and a sheet density. An embodiment, for example, may have: a specific surface area ranging from 1400 to 2300 m.sup.2/g; a pore volume ranging from 0.20 to 0.70 cm.sup.3/g for pores having pore diameters of more than 0.7 nm and 2.0 nm or less; an abundance ratio R.sub.0.7/2.0, which is a ratio of a pore volume of micropores having pore diameters of 0.7 nm or less occupied in a pore volume of micropores having pore diameters of 2.0 nm or less, ranging from 5% to less than 25%, and a sheet density ranging from 0.030 to 0.200 g/cm.sup.3.

The present disclosure relates to a method for the production of precursor fiber for the production of carbon fiber, comprising the steps: a) a) forming a spinning dope comprising a dissolving pulp, a lignin and an alkali metal hydroxide dissolved in water (s201); 5 b) extruding the spinning dope through a spinning nozzle to provide a fibrous extrudate (s203); and c) passing the fibrous extrudate through a coagulation liquid to provide the precursor fiber (s205); wherein the coagulation liquid is arranged to effect precipitation of the precursor fiber by regulation of pH and/or ionicity. The disclosure further relates to precursor fibers and carbon fibers produced by the method above, as well as spinning dopes used in the method.

The present disclosure relates to a method for the production of precursor fiber for the production of carbon fiber, comprising the steps: a) a) forming a spinning dope comprising a dissolving pulp, a lignin and an alkali metal hydroxide dissolved in water (s201); 5 b) extruding the spinning dope through a spinning nozzle to provide a fibrous extrudate (s203); and c) passing the fibrous extrudate through a coagulation liquid to provide the precursor fiber (s205); wherein the coagulation liquid is arranged to effect precipitation of the precursor fiber by regulation of pH and/or ionicity. The disclosure further relates to precursor fibers and carbon fibers produced by the method above, as well as spinning dopes used in the method.

A cooking method and a digester system wherein partly digested cellulosic fiber source is compressed during cooking to provide high molecular weight lignin and pulp.

A process for stabilizing precursor fibers for the production of carbon fibers is disclosed. The process comprises the following steps: continuously introducing, passing and removing said precursor fibers into, through and from a process chamber; establishing a predetermined process gas atmosphere different in composition from ambient air in said at least one process chamber, said process gas atmosphere containing at least one of a reactive component and a catalyst having a predetermined partial pressure; while said precursor fibers are in said process chamber, heating the precursor fibers to at least a first temperature and maintaining said first temperature for a predetermined period of time.

A process for stabilizing precursor fibers for the production of carbon fibers is disclosed. The process comprises the following steps: continuously introducing, passing and removing said precursor fibers into, through and from a process chamber; establishing a predetermined process gas atmosphere different in composition from ambient air in said at least one process chamber, said process gas atmosphere containing at least one of a reactive component and a catalyst having a predetermined partial pressure; while said precursor fibers are in said process chamber, heating the precursor fibers to at least a first temperature and maintaining said first temperature for a predetermined period of time.