Catalyst with improved activity/selectivity for light naphtha aromatization

Patent metadata

Field	Value
Publication number	US-10207255-B2
Application number	US-201415035505-A
Country	US
Kind code	B2
Filing date	Nov 6, 2014
Priority date	Nov 22, 2013
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

In an embodiment, a method for making a catalyst, comprises: forming a mixture comprising a germanium source, an alkali metal source, an aluminum source, and a silica source, wherein the mixture has a pH; adjusting the pH of the mixture to a value of greater than or equal to 9.5; crystallizing and calcining the mixture to form a zeolite; depositing platinum on the zeolite; and calcining the zeolite to form the final catalyst. The final catalyst is non-acidic and has an aluminum content of less than or equal to 0.75 wt % based on the total weight of the final catalyst excluding any binder and extrusion aide and a Si:Al2 mole ratio of greater than or equal to 125.

First claim

We claim:

1. A method for making a catalyst, comprising:
forming a mixture comprising a germanium source, an alkali metal source, an aluminum source, and a silica source, wherein the mixture has a pH;
adjusting the pH of the mixture to a value of 9.5 to less than 13;
crystallizing and calcining the mixture to form a zeolite; a medium pore zeolite having an average pore size of 5 to 8 Å;
depositing platinum on the zeolite; and
calcining the zeolite to form the final catalyst;
wherein the final catalyst is non-acidic and has an aluminum content of less than or equal to 0.75 wt % based on the total weight of the final catalyst excluding any binder or extrusion aide, and a final Si:Al 2 mole ratio of 125 to 211;
wherein the final catalyst has a Ge content of 0.1 to 3 wt % based on the total weight of the final catalyst excluding any binder and extrusion aide.

2. The method of claim 1 , wherein the forming of the mixture comprises:
forming a first aqueous solution, wherein the first solution comprises the germanium source and the alkali metal source;
forming a second aqueous solution, wherein the second solution comprises the aluminum source;
combining the first and second aqueous solutions to form a combined solution; and
adding the silica source to the combined solution to form the mixture.

3. The method of claim 1 , wherein the mixture has a mixture Si:Al 2 mole ratio of 175 to 290, a mixture Si:Ge mole ratio of 5 to 100, and a mixture Na:Al mole ratio of 10 to 60.

4. The method of claim 1 , wherein the zeolite is a ZSM-5 zeolite.

5. The method of claim 1 , wherein the final catalyst has one or both of a final Si:Ge mole ratio of 40 to 400 and a final Na:Al mole ratio of 0.9 to 2.5.

6. The method of claim 1 , wherein the Ge content is 0.4 to 2.5 wt %, or wherein the final catalyst has an Na content of 0.5 to 2 wt %, or wherein the final catalyst has a Pt content of 0.05 to 3 wt %, wherein the wt % values are based on the total weight of the final catalyst excluding any binder and extrusion aide.

7. The method of claim 1 , wherein the method does not include an ion-exchange step with an alkali metal.

8. The method of claim 1 , wherein the final catalyst is free of cesium.

9. The method of claim 1 , wherein the alkali metal source comprises at least one of a sodium source and a potassium source.

10. The method of claim 1 , wherein the alkali metal source comprises at least one of NaOH and NaCl.

11. The method of claim 1 , wherein the pH is 9.5 to 12.5.

12. The method of claim 1 , wherein the final catalyst has a Ge content of 0.4 to 1.5 wt % based on the total weight of the final catalyst excluding any binder and extrusion aide.

13. The method of claim 1 , wherein the final catalyst comprises Al in an amount of 0.45 to 0.7 wt % based on the total weight of the final catalyst excluding any binder and extrusion aide.

14. The method of claim 1 , wherein the Ge content is 0.4 to 2.5 wt %, wherein the final catalyst has an Na content of 0.5 to 2 wt %, and wherein the final catalyst has a Pt content of 0.05 to 3 wt %, wherein the wt % values are based on the total weight of the final catalyst excluding any binder and extrusion aide.

15. The method of claim 1 , wherein the final Si:Al 2 mole ratio is 125 to 200.

Assignees

• Saudi Basic Ind Corp

Inventors

• Khanmamedova Alla
• Stevenson Scott

Classifications

• C10G45/12

  containing crystalline alumino-silicates, e.g. molecular sieves · CPC title

• B01J23/42

  Platinum · CPC title

• C10G45/10

  containing platinum group metals or compounds thereof · CPC title

• C07C2/76

  by condensation of hydrocarbons with partial elimination of hydrogen · CPC title

• C07C2529/40

  of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11 · CPC title