Method for the fluidized catalytic cracking of a heavy hydrocarbon feedstock

Patent metadata

Field	Value
Publication number	US-9605213-B2
Application number	US-201615015448-A
Country	US
Kind code	B2
Filing date	Feb 4, 2016
Priority date	May 25, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

Embodiments of the invention provide a method for the fluid catalytic cracking of a heavy hydrocarbon feedstock. According to at least one embodiment, the method includes supplying the heavy hydrocarbon feedstock to a reaction zone having a catalyst, such that both the heavy hydrocarbon feedstock and the catalyst are in contact in a down-flow mode, wherein said contact between the heavy hydrocarbon feedstock and the catalyst takes place in a fluidized catalytic cracking apparatus having a separation zone, a stripping zone, and a regeneration zone. The method further includes maintaining the reaction zone at a temperature of between 500 and 600° C., such that the hydrocarbon feedstock converts into a cracked hydrocarbon effluent comprising light olefins, gasoline, and diesel. The catalyst includes between 10 and 20% by weight of a phosphorous modified sub-micron ZSM-5, between 10 and 20% by weight of an ultra-stable Y-type zeolite, between 20 and 30% by weight of a pseudoboehmite alumina, and between 20 and 40% by weight of kaolin. The phosphorous modified sub-micron ZSM-5 has an average crystal size between 50 and 400 nm, inclusive, and a silica to alumina ratio of 1:2 to 1:4, inclusive.

First claim

That which is claimed is:

1. A method for the fluid catalytic cracking of a heavy hydrocarbon feedstock, the method comprising:
supplying the heavy hydrocarbon feedstock to a reaction zone comprising a catalyst, such that both the heavy hydrocarbon feedstock and the catalyst are in contact in a down-flow mode, wherein said contact between the heavy hydrocarbon feedstock and the catalyst takes place in a fluidized catalytic cracking apparatus comprising a separation zone, a stripping zone, and a regeneration zone; and
maintaining the reaction zone at a temperature of between 500 and 600° C., such that the hydrocarbon feedstock converts into a cracked hydrocarbon effluent comprising light olefins, gasoline, and diesel,

wherein the catalyst comprises 30% by weight of a phosphorous modified sub-micron ZSM-5, 10% by weight of an ultra-stable Y-type zeolite, 20% by weight of a pseudoboehmite alumina, and 40% by weight of kaolin, and
wherein the phosphorous modified sub-micron ZSM-5 has an average crystal size between 50 and 400 nm, inclusive, and a silica to alumina ratio of 1:2 to 1:4, inclusive.

2. The method of claim 1 , wherein the reaction zone is a downer of a fluidized catalytic cracking unit.

3. The method of claim 1 , wherein the phosphorous modified sub-micron ZSM-5 includes phosphorous in a range of 5 to 10% by weight of the phosphorous modified sub-micron ZSM-5.

4. The method of claim 1 , wherein the heavy hydrocarbon feedstock comprises one of a hydrotreated or an un-hydrotreated VGO.

5. The method of claim 1 , further comprising:
regenerating deactivated catalyst at a temperature of at least 700° C. using a source of oxygen and supplying the deactivated catalyst to the reaction zone.

6. The method of claim 5 , wherein an amount of the oxygen introduced to the regeneration zone is such that a carbon-to-oxygen ratio is 2:5.

7. The method of claim 1 , wherein the temperature in the reaction zone is maintained such that light olefins of the cracked hydrocarbon effluent comprise C 2 -C 4 olefins.

8. The method of claim 7 , wherein a yield of C 2 -C 4 olefins of the cracked hydrocarbon effluent is greater than 20% by weight.

9. The method of claim 7 , wherein a combined yield of propylene and ethylene is greater than a yield of butenes in the cracked hydrocarbon effluent.

10. The method of claim 7 , wherein a yield by weight of propylene is greater than a yield by weight of butenes in the cracked hydrocarbon effluent.

11. The method of claim 7 , wherein a yield of propylene is greater than 14% by weight.

12. The method of claim 1 , wherein a yield of gasoline is greater than 30% by weight.

13. The method of claim 12 , wherein the gasoline has a GC-RON value greater than 88.

14. The method of claim 12 , wherein the light olefins content of the gasoline has a value less than 20% by weight.

Assignees

• Saudi Arabian Oil Co
• Univ King Fahd Pet & Minerals

Inventors

• Al-Ghrami Musaed Salem
• Ercan Cemal
• Al-Khattaf Sulaiman S
• Siddiqui Mohammed Abdul Bari
• Aitani Abdullah M

Classifications

• C10G2400/20

  C2-C4 olefins · CPC title

• B01J2229/186

  not in framework positions · CPC title

• C07C4/06

  Catalytic processes {(C07C4/025 takes precedence)} · CPC title

• C10G11/182

  Regeneration · CPC title

• B01J37/28

  Phosphorising · CPC title