Adsorbent bed with increased hydrothermal stability

Patent metadata

Field	Value
Publication number	US-12083471-B2
Application number	US-202117246583-A
Country	US
Kind code	B2
Filing date	Apr 30, 2021
Priority date	May 1, 2020
Publication date	Sep 10, 2024
Grant date	Sep 10, 2024

Abstract

Disclosed in certain embodiments are methods of removing water from a gas feed stream comprising hydrocarbons and water during an adsorption step of an adsorption cycle.

First claim

What is claimed is:

1. A method of removing water from a gas feed stream comprising hydrocarbons and water during an adsorption step of an adsorption cycle, the method comprising:
directing the gas feed stream having an initial water mole fraction toward an adsorbent bed, the adsorbent bed comprising:
a first adsorbent layer comprising an adsorbent that is preferentially selective for C6+ hydrocarbons and comprises one or more of an amorphous silica adsorbent, an amorphous silica-alumina adsorbent, or a high-silica zeolite adsorbent, wherein a weight percent (wt. %) of the first adsorbent layer with respect to the total weight of the adsorbent bed is greater than 50 wt. %; and
a second adsorbent layer downstream from the first adsorbent layer to remove remaining water, the second adsorbent layer comprising a zeolite,

wherein, after passing through the first adsorbent layer, the gas feed stream has a reduced water mole fraction that is less than or equal to 10% of the initial water mole fraction when the gas feed stream reaches the second adsorbent layer.

2. The method of claim 1 , wherein the reduced water mole fraction is less than or equal to about 100 ppm.

3. The method of claim 1 , wherein the first adsorbent layer comprises the high-silica zeolite adsorbent.

4. The method of claim 1 , wherein the second adsorbent layer comprises one or more of zeolite A, zeolite X, or zeolite Y.

5. The method of claim 1 , wherein the adsorbent bed further comprises a third adsorbent layer downstream from the second adsorbent layer, the third adsorbent layer comprising an amorphous silica adsorbent or an amorphous silica-alumina adsorbent.

6. The method of claim 1 , wherein the adsorbent bed further comprises a third adsorbent layer downstream from the second adsorbent layer, the third adsorbent layer comprising zeolite X or zeolite Y.

7. The method of claim 1 , wherein the adsorbent bed further comprises a third adsorbent layer downstream from the second adsorbent layer, the third adsorbent layer having a higher selectivity to n-pentane over methane.

8. The method of claim 1 , wherein the adsorbent bed further comprises a third adsorbent layer upstream from the first adsorbent layer, the third adsorbent layer comprising a water stable adsorbent.

9. The method of claim 1 , wherein the gas feed stream is a natural gas feed stream.

10. The method of claim 1 , wherein a final water mole fraction of the gas feed stream leaving the adsorbent bed is below 1 ppm or below 0.1 ppm.

11. The method of claim 1 , further comprising:
forming a liquefied natural gas product from the gas feed stream after leaving the adsorbent bed.

12. The method of claim 1 , further comprising:
forming a C2+ or C3+ natural gas liquid feed stream from the gas feed stream after leaving the adsorbent bed.

13. The method of claim 1 , wherein the method is performed as part of a thermal swing adsorption process having a cycle time of less than or equal to about 8 hours, about 7 hours, about 6 hours, about 5 hours, about 4 hours, about 3 hours, about 2 hours, or about 1 hour.

14. The method of claim 1 , wherein one or more components of the hydrocarbons in the gas feed stream is reduced by 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, or 5% on a molar basis relative to an initial concentration of that component in the gas feed stream, wherein the one or more components are selected from a group consisting of benzene, C9 hydrocarbons, C8 hydrocarbons, C7 hydrocarbons, C6 hydrocarbons, and C5 hydrocarbons.

15. The method of claim 1 , further comprising:
prior to directing the gas feed stream toward the adsorbent bed, retrofitting the adsorbent bed by removing and replacing at least a portion of a previously present adsorbent with one or more of the first adsorbent layer or the second adsorbent layer.

Assignees

• Basf Corp

Inventors

• Dolan William B
• Pan Justin
• Maglio Alfonse
• Greene Margaret Anne
• Eckardt Tobias

Classifications

• B01J20/28052

  Several layers of identical or different sorbents stacked in a housing, e.g. in a column · CPC title

• B01J20/18

  Synthetic zeolitic molecular sieves · CPC title

• B01J20/103

  comprising silica · CPC title

• B01J20/08

  comprising aluminium oxide or hydroxide; comprising bauxite · CPC title

• B01D2257/7022

  Aliphatic hydrocarbons · CPC title