Steam cracking process for converting crude oils to pitch compositions spinnable into carbon articles

Patent metadata

Field	Value
Publication number	US-12570905-B2
Application number	US-202118251676-A
Country	US
Kind code	B2
Filing date	Nov 10, 2021
Priority date	Jan 6, 2021
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

Pitch compositions may be obtained by subjecting one or more crude oils to steam cracking. Processes for producing pitch compositions suitable for spinning into fibers from steam cracking of crude oils may comprise: steam cracking of one or more crude oils in a steam cracking zone to produce a first effluent comprising a heavy oil mixture comprising a steam cracker tar, a second effluent comprising a mixture of gaseous products and liquid products, and a third effluent comprising one or more bottoms products; pretreating and heat treating the first, second and/or third effluent to produce a pitch composition having a mesophase content from 0 vol % to 100 vol %, based on the total volume of the pitch product, an MCR in the range of about 40 wt % to about 95 wt %, and a softening point T sp in the range of about 50° C. to about 400° C.

First claim

What is claimed is:

1 . A process comprising:
steam cracking of one or more crude oils in a steam cracking zone to produce a first effluent comprising a heavy oil mixture comprising a steam cracker tar, a second effluent comprising a mixture of gaseous products and liquid products, and a third effluent comprising one or more bottoms products; optionally introducing at least a portion of the first effluent from downstream of the steam cracking zone and/or at least a portion of the second effluent from downstream of the steam cracking zone and/or at least a portion of the third effluent from downstream of the steam cracking zone to one or more pretreating zones to produce a first effluent pretreated product and/or a second effluent pretreated product and/or a third effluent pretreated product; introducing the first effluent, the first effluent pretreated product, the second effluent, the second effluent pretreated product, the third effluent, the third effluent pretreated product, or any combination thereof, to a reaction zone; and heat treating the first effluent, the first effluent pretreated product, the second effluent, the second effluent pretreated product, the third effluent, the third effluent pretreated product, or any combination thereof, in the reaction zone to a temperature in a range of about 200° C. to about 800° C. to produce a first reaction effluent comprising a pitch product, and a second reaction effluent comprising a mixture of gaseous and liquid products, wherein the pitch product has an MCR in a range of about 40 wt. % to about 95 wt. %, and a softening point Tsp in a range of about 50° C. to about 400° C., wherein the first effluent is sent directly to the reaction zone without introducing to the one or more pretreating zones and the first reaction effluent, the second reaction effluent, or both the first and second reaction effluents are sent to a separation zone after heat treating to produce at least one pitch product and a separated reaction effluent comprised of gaseous and liquid hydrocarbons; and wherein the at least one pitch product following separation has a mesophase content from 5 vol % to 100 vol %, based on a total volume of the at least one pitch product, an MCR in a range of about 40 wt. % to about 95 wt. %, based on a total weight of the at least one pitch product, and a softening point Tsp in a range of about 50° C. to about 400° C.

2 . The process of claim 1 , wherein the one or more pretreating zones are one or more hydrotreating zones, wherein at least a portion of the first effluent is hydrotreated to produce the first effluent pretreated product, and wherein the first effluent pretreated product is a hydrotreated first effluent product.

3 . The process of claim 1 , wherein the pitch product has a stack height (LC) of about 2 nm to about 9 nm, as determined by X-ray scattering.

4 . The process of claim 3 , further comprising:
separating the first reaction effluent and the second reaction effluent in a separation zone to produce at least one pitch product, and a separated reaction effluent comprised of gaseous and liquid hydrocarbons, wherein the at least one pitch product has a mesophase content from 5 vol % to 100 vol %, based on a total volume of the at least one pitch product, an MCR in a range of about 40 wt. % to about 95 wt. %, based on a total weight of the at least one pitch product, and a softening point Tsp in a range of about 50° C. to about 400° C.

5 . The process of claim 1 , wherein the third effluent comprising one or more bottoms products is sent to a first separation zone to produce at least a first separation product and a second separation product, wherein at least a portion of the first separation product, or at least a portion of the second separation product is sent to a reaction zone to produce a reaction effluent.

6 . The process of claim 5 , further comprising:
separating the reaction effluent produced from at least a portion of the first separation product, or at least a portion of the second separation product to a second separation zone to produce at least one pitch product, and a separated reaction effluent comprised of gaseous and liquid hydrocarbons, wherein the at least one pitch product has an MCR in the range of about 40 wt. % to about 95 wt. %, based on a total weight of the at least one pitch product, and a softening point Tsp in a range of about 50° C. to about 400° C.

7 . The process of claim 1 , wherein the first effluent has at least about 70 wt. % of the mixture having a boiling point at atmospheric pressure that is greater than about 200° C., an MCR of about 5 wt. % to about 55 wt. %, a hydrogen content of about 4 wt. % to about 10 wt. %, a sulfur content of about 5 wt. % or less, based on a total weight of the first effluent.

8 . The process of claim 1 , wherein the pitch product has (1) a quinoline insoluble (QI) content of about 60 wt. % or less, (2) a Tsp of about 100° C. or greater, (3) a Tg of about 70° C. or greater, or (4) a combination thereof.

9 . The process of claim 1 , wherein the pitch product is sent to one or more heat treating zones to produce a heat treated pitch product having an MCR and a Tsp both greater than the MCR and the Tsp of the pitch product, and wherein the pitch product and/or the heat treated pitch product are suitable for spinning into carbon fiber.

10 . The process of claim 9 , wherein the heat treated pitch product has one or more of: a mesophase content of about 50 vol % or greater, based on a total volume of the heat treated pitch product; a quinoline insoluble (QI) content of about 10 wt. % or greater, based on the total weight of the heat treated pitch product; and a Tsp of about 200° C. or greater.

11 . The process of claim 2 , wherein the hydrotreated first effluent product has a T50 in a range of about 225° C. to about 375° C., a hydrogen content of about 7 wt. % to about 12 wt. %, and a sulfur content of from 0 wt. % to about 1 wt. %, based on a total weight of the hydrotreated first effluent product.

12 . The process of claim 2 , further comprising:
separating the hydrotreated first effluent product downstream of a hydrotreating zone to produce at least a liquid effluent; and recycling the liquid effluent back to an upstream of the hydrotreating zone.

13 . The process of claim 11 , wherein the third effluent comprises one or more bottoms products and wherein the process further comprising:
separating the one or more bottoms products by deasphaltenation in the presence of a solvent to produce a first portion comprising solvent and soluble compounds, and a second portion comprising solvent and a deasphalted bottom product, wherein the deasphalted bottom product comprises a third pitch product having a softening point Tsp of about 25° C. or greater, a hydrogen content of about 4 wt. % to about 12 wt. %, based on a total weight of the third pitch product, and an MCR of from about 10 wt. % to about 60 wt. %, based on the total weight of the third pitch product, wherein the third pitch product is suitable for spinning into carbon fiber.

14 . The process of claim 13 , further comprising:
performing a vacuum distillation on at least a portion of the deasphalted bottom product to produce a vacuum gas oil product and a vacuum bottoms product; and producing a fuel oil from at least a portion of the vacuum gas oil product, wherein the fuel oil has a sulfur content of about 1 wt. % or less.

15 . The process of claim 1 further comprising:
solvent deasphalting at least a portion of the third effluent in a deasphalting unit to produce a deasphalted oil fraction and a d

Assignees

• Exxonmobil Technology & Engineering Company

Inventors

• Smith Stuart E
• Chase Clarence E
• Edmond Kazem V
• Gopinadhan Manesh
• Ferrughelli David T

Classifications

• D01F9/155

  from petroleum pitch · CPC title

• C10G2300/202

  Heteroatoms content, i.e. S, N, O, P · CPC title

• C10G69/06

  including at least one step of thermal cracking in the absence of hydrogen · CPC title

• C10G67/0454

  Solvent desasphalting · CPC title

• C10G9/36 Primary

  with heated gases or vapours · CPC title