Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: This document describes methods for pretreating coal to create either a dried coal or a char product that is stable in the outdoor environment and is more efficient as a feedstock for gasification or other processes than the original coal. Embodiments of the methods include pulverizing and pelletizing the coal, and pretreating the coal pellets to obtain a stable pellet of either dried coal or a stable pellet of chared coal (coal char). The pellets created by the described methods have undergone deoxygenation and carbonization improving their handling and storage properties and, in some cases, energy density. Pore structures within the pellets are stabilized physically and chemically so that the uptake of moisture into dry coal, that leads to internal heat generation, is greatly reduced. Chars are also, therefore, stable against transitions from a dry state to a wet state and less prone to self-ignition.

Abstract: Examples of a flexible pyrolysis system are provided that include at least one reaction chamber capable of pyrolyzing a combination of coal in a supercritical carbon dioxide (CO2) atmosphere. The system includes a recuperating and condensing circuit that removes dissolved pyrolysis products from the supercritical CO2 atmosphere and then recovers CO2 for reuse in the reaction chamber. The recuperating and condensing circuit includes multiple stages of recuperators and collectors that can be independently controlled in order to selectively fractionate the pyrolysis products. In addition, the pyrolysis reaction may be controlled to alter the pyrolysis products generated.

Abstract: Examples of a flexible pyrolysis system are provided that include at least one reaction chamber capable of pyrolyzing a combination of coal in a supercritical carbon dioxide (CO2) atmosphere. The system includes a recuperating and condensing circuit that removes dissolved pyrolysis products from the supercritical CO2 atmosphere and then recovers CO2 for reuse in the reaction chamber. The recuperating and condensing circuit includes multiple stages of recuperators and collectors that can be independently controlled in order to selectively fractionate the pyrolysis products. In addition, the pyrolysis reaction may be controlled to alter the pyrolysis products generated.

Abstract: Embodiments of methods for improving mesophase pitch for carbon fiber production using supercritical carbon dioxide are described. The methods improve the relative amount and quality of mesophase pitch in feedstocks, such as coal tar, already having at least some mesophase pitch. One particular method includes performing a sCO2/toluene extraction on the coal tar to obtain a toluene insoluble fraction of the coal tar; mixing the toluene insoluble fraction with sCO2 to obtain a sCO2/toluene insoluble fraction mixture; and extruding the sCO2/toluene insoluble fraction mixture, thereby separating the sCO2 from the toluene insoluble fraction to obtain fibers of mesophase pitch.

Abstract: This document describes methods for pretreating coal to create either a dried coal or a char product that is stable in the outdoor environment and is more efficient as a feedstock for gasification or other processes than the original coal. Embodiments of the methods include pulverizing and pelletizing the coal, and pretreating the coal pellets to obtain a stable pellet of either dried coal or a stable pellet of chared coal (coal char). The pellets created by the described methods have undergone deoxygenation and carbonization improving their handling and storage properties and, in some cases, energy density. Pore structures within the pellets are stabilized physically and chemically so that the uptake of moisture into dry coal, that leads to internal heat generation, is greatly reduced. Chars are also, therefore, stable against transitions from a dry state to a wet state and less prone to self-ignition.

Abstract: Examples of a flexible pyrolysis system are provided that include at least one reaction chamber capable of pyrolyzing a combination of coal in a supercritical carbon dioxide (CO2) atmosphere. The system includes a recuperating and condensing circuit that removes dissolved pyrolysis products from the supercritical CO2 atmosphere and then recovers CO2 for reuse in the reaction chamber. The recuperating and condensing circuit includes multiple stages of recuperators and collectors that can be independently controlled in order to selectively fractionate the pyrolysis products. In addition, the pyrolysis reaction may be controlled to alter the pyrolysis products generated.