Naphtha hydrotreating process

Patent metadata

Field	Value
Publication number	US-11015129-B2
Application number	US-202016845118-A
Country	US
Kind code	B2
Filing date	Apr 10, 2020
Priority date	Apr 12, 2019
Publication date	May 25, 2021
Grant date	May 25, 2021

Abstract

A naphtha hydrotreating process containing
a first step in the presence of the first catalyst containing a support;
a second step in the presence of the second catalyst containing a support and an active phase, which active phase contains a Group 9 or 10 metal and a Group 6 metal;
a third step in the presence of the third catalyst containing a support and an active phase, which active phase contains a Group 6 metal;
wherein
the content of Group 6 metal of the third catalyst is less than the content of Group 6 metal of the second catalyst;
the ratio of the loaded specific surface area of the first catalyst to that of the second catalyst is greater than or equal to 1.20;
the ratio of the loaded specific surface area of the third catalyst to that of the second catalyst is greater than 1.07.

First claim

The invention claimed is:

1. A naphtha hydrotreating process performed in the presence of at least a first catalyst, a second catalyst and a third catalyst, each of said catalysts having a loaded specific surface area, L 1 , L 2 and L 3 , respectively, corresponding to the specific surface area by mass multiplied by the loaded density of the respective catalysts,
said process comprising three successive steps through each of which the naphtha is passed through:
a first step a) in the presence of the first catalyst having loaded specific surface area L 1 , said first catalyst comprising a support and optionally an active phase, said active phase containing at least one Group 6 metal and optionally at least one Group 9 or 10 metal;
a second step b) in the presence of the second catalyst having loaded specific surface area L 2 , said second catalyst comprising a support and an active phase, said active phase containing at least one Group 9 or 10 metal and at least one Group 6 metal;
a third step c) in the presence of the third catalyst having loaded specific area L 2 , said third catalyst comprising a support and an active phase, said active phase containing at least one Group 6 metal and optionally at least one Group 9 or 10 metal;
wherein a hydrotreated naphtha is produced, and
wherein
the content of Group 6 metal of the third catalyst is less than the content of Group 6 metal of said second catalyst;
the ratio L 1 /L 2 is greater than or equal to 1.20;
the ratio L 3 /L 2 is greater than 1.07.

2. The process according to claim 1 , in which said first catalyst comprises an active phase,
and wherein the content of Group 6 metal of said first catalyst is less than the content of Group 6 metal of said second catalyst.

3. The process according to claim 2 , in which the active phase of the first catalyst contains at least one Group 9 or 10 metal,
and wherein
the content of Group 9 or 10 metal of said active phase of the first catalyst is greater than or equal to 0.5% by weight and less than 3% by weight;
the content of Group 9 plus 10 metal of said active phase of the first catalyst is less than the content of Group 9 plus 10 metal of said second catalyst.

4. The process according to claim 2 , in which the active phase of the first catalyst contains at least one Group 9 or 10 metal,
and wherein
the content of Group 9 or 10 metal of said first catalyst is greater than or equal to 3% by weight and less than or equal to 9% by weight;
the content of Group 9 plus 10 metal of the first catalyst is greater than the content of Group 9 plus 10 metal of said second catalysts.

5. The process according to claim 1 , in which said first catalyst consists of a support without an active phase.

6. The process according to claim 1 , in which the active phase of the third catalyst contains at least one Group 9 or 10 metal,
and wherein the content of Group 9 plus 10 metal of the third catalyst is less than the content of Group 9 plus 10 metal of said second catalyst.

7. The process according to claim 1 , in which the liquid hourly space velocity of the first step is less than or equal to 20 times the overall liquid hourly space velocity and greater than or equal to 1.33 times the overall liquid hourly space velocity.

8. The process according to claim 1 , in which the liquid hourly space velocity of the second step is less than or equal to 4 times the overall liquid hourly space velocity and greater than or equal to 1.33 times the overall liquid hourly space velocity.

9. The process according to claim 1 , in which the liquid hourly space velocity of the third step is greater than or equal to 5 times the overall liquid hourly space velocity and less than or equal to 20 times the overall liquid hourly space velocity.

10. The process according to claim 1 , in which the first or third catalyst contains molybdenum alone, or nickel and molybdenum, or cobalt and molybdenum, or nickel and cobalt and molybdenum.

11. The process according to claim 1 , in which the second catalyst contains nickel and molybdenum, or cobalt and molybdenum, or nickel and cobalt and molybdenum.

12. The process according to claim 1 , in which said naphtha comprises hydrocarbons comprising from 10 to 50 000 ppm by weight of one or more sulfur-based compounds.

13. The process according to claim 1 , in which said naphtha comprises a cracked naphtha feedstock, alone or as a mixture with a different naphtha feedstock.

14. The naphtha hydrotreating process according to claim 1 , which produces a hydrodesulfurized naphtha, further comprising
an optional step of hydrogenation of diolefins, producing a naphtha with a reduced content of diolefins;
a step of separation of at least part of the hydrodesulfurized naphtha to remove H 2 S and optional production of an LPG fraction or of an uncondensable stream;
an optional step of separating the hydrodesulfurized naphtha into at least two naphtha fractions.

15. A naphtha hydrotreating reactor comprising a reaction section containing at least three catalysts, said catalyst being loaded onto first, second and third successive layers of catalyst and each of said catalysts having a loaded specific surface area L 1 , L 2 and L 3 , respectively, corresponding to its specific surface area by mass multiplied by its loaded density,
the first layer of catalyst contains the first catalyst comprising a support and optionally an active phase, said active phase containing at least one Group 6 metal and optionally at least one Group 9 or 10 metal;
the second layer of catalyst contains the second catalyst comprising a support and an active phase, said active phase containing at least one Group 9 or 10 metal and at least one Group 6 metal;
the third layer of catalyst contains the third catalyst comprising a support and an active phase, said active phase containing at least one Group 6 metal and optionally at least one Group 9 or 10 metal;
and wherein
the content of Group 6 metal of the third catalyst is less than the content of Group 6 metal of the second catalyst;
the ratio L 1 /L 2 is greater than or equal to 1.20;
the ratio L 3 /L 2 is greater than 1.07.

16. The naphtha hydrotreating reactor according to claim 15 , which is a fixed catalytic bed reactor with axial flow.

17. The naphtha hydrotreating process according to claim 3 , wherein the content of Group 6 metal of said first catalyst is greater than or equal to 0.5% by weight and less than or equal to 6% by weight.

18. The naphtha hydrotreating process according to claim 4 , wherein the content of Group 6 metal of said first catalyst is greater than 6% by weight and less than or equal to 10% by weight.

19. The naphtha hydrotreating process according to claim 3 , wherein the
the ratio L 1 /L 2 is greater than or equal to 1.35; and
the ratio L 3 /L 2 is greater than or equal to 1.35.

Assignees

• Axens

Inventors

• Dubin Geoffrey
• Pucci Annick
• Hesse Boris

Classifications

• C10G2300/207

  Acid gases, e.g. H2S, COS, SO2, HCN · CPC title

• C10G2300/1044

  Heavy gasoline or naphtha having a boiling range of about 100 - 180 °C · CPC title

• C10G69/08

  including at least one step of reforming naphtha · CPC title

• C10G45/32

  Selective hydrogenation of the diolefin or acetylene compounds · CPC title

• C10G35/24

  Controlling or regulating of reforming operations · CPC title