Pitch compositions and methods related thereto

Abstract

Pitch compositions having controlled pitch composition properties and methods for their production and use. Pitch properties are predicted based on infrared structural parameters and two or more pitch compositions may be blended to achieve desired pitch properties, including softening point, microcarbon residue, hydrogen to carbon ratio, and percent pitch volatiles. Predicting these properties can aid in, among other things, end-use optimization of the production of spinnable pitches for carbon fibers, mesocarbon microbeads, matrixes for carbon/carbon composites, and other pitch-derived carbon products.

What is claimed is: 
     
         1 . A composition comprising:
 a pitch composition having one or both of an A-Factor in the range of about 0.4 to about 0.8 and/or an Aromaticity in the range of about 0.3 to about 1.3.   
     
     
         2 . The composition of  claim 1 , wherein the A-Factor is in the range of about 0.6 to about 0.8 and the Aromaticity is in the range of about 0.3 to about 0.6. 
     
     
         3 . The composition of  claim 1 , further comprising a softening point in the range of about 90° C. to about 150° C. and a mesophase by volume of less than about 20%. 
     
     
         4 . The composition of  claim 1 , wherein the A-Factor is in the range of about 0.4 to about 0.6 and the Aromaticity is in the range of about 0.5 to about 0.8. 
     
     
         5 . The composition of any one of  claim 1  further comprising a softening point in the range of about 250° C. to about 350° C. and a mesophase by volume of greater than about 30%. 
     
     
         6 . The composition of any one of  claim 1 , further comprising a softening point in the range of about 150° C. to about 350° C. and a mesophase by volume of greater than about 50%. 
     
     
         7 . The composition of  claim 1 , wherein the pitch composition is composed of a blend of pitches comprised of at least a first pitch composition and a second pitch composition. 
     
     
         8 . A method comprising:
 pyrolyzing at least a first pitch composition from a first pitch feed and a second pitch composition from a second pitch feed;
 wherein the pyrolyzing of the first pitch composition and the second pitch composition are performed separately; 
   obtaining a first infrared spectrum of the at least first pitch composition and selecting at least one first infrared parameter based on (1) the first infrared spectrum and a calibration curve or (2) the first infrared spectrum and chemometric modeling;   obtaining a second infrared spectrum of the at least second pitch composition and selecting at least one second infrared parameter based on (1) the second infrared spectrum and a calibration curve or (2) the second infrared spectrum and chemometric modeling; and
 wherein the selected first and second infrared parameters are at least one or both of an A-Factor in a range of about 0.4 to about 0.8 and/or an Aromaticity in a range of about 0.3 to about 1.3; and 
   blending the first and second pitch compositions in a ratio to achieve the selected first and second infrared parameters, thereby forming a blended pitch composition.   
     
     
         9 . The method of  claim 8 , wherein the selected first and second infrared parameters further include a softening point in the range of about 90° C. to about 150° C. and a mesophase by volume of less than about 20%. 
     
     
         10 . The method of  claim 8 , wherein the selected first and second infrared parameters further include a softening point in the range of about 250° C. to about 350° C. and a mesophase by volume of greater than about 30%. 
     
     
         11 . The method of  claim 8 , wherein the selected first and second infrared parameters further include a softening point in the range of about 150° C. to about 350° C. and a mesophase by volume of greater than about 50%. 
     
     
         12 . The method of  claim 8 , further comprising spinning or producing one or both of a carbon fiber and/or a carbon fiber composite with the blended pitch. 
     
     
         13 . The method of  claim 8 , further comprising producing one or more of mesocarbon microbeads, graphite, and/or needle coke with the blended pitch. 
     
     
         14 . The method of  claim 8 , further comprising:
 prior to the pyrolyzing:
 obtaining a first initial infrared spectrum of the first pitch feed and selecting at least one first initial infrared parameter based on (1) the first initial infrared spectrum and a calibration curve or (2) the first initial infrared spectrum and chemometric modeling; 
 obtaining a second initial infrared spectrum of the second pitch feed and selecting at least one second initial infrared parameter based on (1) the second initial infrared spectrum and a calibration curve or (2) the second initial infrared spectrum and chemometric modeling; and 
 wherein the selected first and second initial infrared parameters are one or both of an initial A-Factor outside of a range of about 0.4 to about 0.8 and/or an initial Aromaticity outside of a range of about 0.3 to about 1.3. 
   
     
     
         15 . The method of  claim 14 , wherein the pyrolyzing further comprises contacting the first and the second pitch feeds with a reactive gas, at a temperature in the range of about 200° C. to about 600° C., and at a pressure greater than 0.3 psi, thereby producing a first pitch effluent comprising the first pitch composition and a second pitch effluent comprising the second pitch composition. 
     
     
         16 . The method of  claim 15 , further comprising:
 after the pyrolyzing:
 separating the first pitch composition from the first pitch effluent and separating the second pitch composition from the second pitch effluent, wherein the separating is selected from distillation separating, deasphalting separation, membrane separation, or any combination thereof. 
   
     
     
         17 . The method of  claim 15 , wherein the reactive gas is selected from the group consisting of hydrogen, air, oxygen, ozone, hydrogen peroxide, carbon monoxide, carbon dioxide, formic acid, nitrogen dioxide, and any combination thereof. 
     
     
         18 . A method comprising:
 extruding a pitch composition to produce a green carbon fiber; and   thereafter, stabilizing the extruded pitch composition;
 wherein the stabilizing comprises obtaining an infrared spectrum of the extruded pitch composition and selecting at least one infrared parameter based on (1) the first infrared spectrum and a calibration curve or (2) the first infrared spectrum and chemometric modeling, 
 wherein the at least one infrared parameter is at least an A-Factor and an Aromaticity; and 
   ceasing stabilizing based upon the at least one infrared parameter.   
     
     
         19 . The method of  claim 18 , wherein the pitch composition is extruded through a spinneret and the method further comprises spooling the extruded pitch composition prior to the stabilizing, wherein the stabilizing is performed with a reactive gas. 
     
     
         20 . The method of  claim 18 , wherein the extruding comprising blowing the pitch composition through an extrusion die. 
     
     
         21 . The method of  claim 18 , wherein the reactive gas is selected from the group consisting of hydrogen, air, oxygen, ozone, nitrogen dioxide, hydrogen peroxide, carbon monoxide, carbon dioxide, formic acid, and any combination thereof. 
     
     
         22 . The method of  claim 18 , wherein the selected at least one infrared parameter is at least one or both of an A-Factor and an Aromaticity, and the stabilizing is ceased when the A-Factor is in a range of about 0.4 to about 0.8 and/or the Aromaticity in a range of about 0.3 to about 1.3.