Zeolite with encapsulated platinum

Patent metadata

Field	Value
Publication number	US-11247196-B2
Application number	US-201916703405-A
Country	US
Kind code	B2
Filing date	Dec 4, 2019
Priority date	Dec 4, 2019
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

A method of making a zeolite with encapsulated platinum is provided. The method includes dissolving an aluminum source in water to form a first solution, dissolving a hydroxide in water to form a second solution, dissolving a templating agent in water to form a third solution, and adding a silica source to the first solution to form a fourth solution. The method further includes adding the second solution to the fourth solution to form a fifth solution, adding the third solution to the fifth solution to form a sixth solution, and adding a platinum source to the sixth solution. The sixth solution is crystallized to form a solid product, which is recovered. The solid product is calcined. An ammonium ion exchange is performed on the solid product to form a second solid product, and the second solid product is calcined.

First claim

What is claimed is:

1. A method of making a ZSM-11 zeolite with encapsulated platinum, comprising:
dissolving an aluminum source in water to form a first solution;
dissolving a hydroxide in water to form a second solution;
dissolving a templating agent in water to form a third solution, wherein the templating agent is tetrabutyl ammonium hydroxide (TBAOH);
adding a silica source to the first solution to form a fourth solution;
adding the second solution to the fourth solution to form a fifth solution;
adding the third solution to the fifth solution to form a sixth solution;
adding a platinum source to the sixth solution;
crystallizing the sixth solution to form a solid product;
recovering the solid product;
calcining the solid product to form a platinum impregnated sodium ZSM-11 (Pt/NaZSM-11;
performing an ammonium ion exchange on the Pt/NaZSM-11 to form Pt/NH 4 ZSM-11; and
calcining the Pt/NH 4 ZSM-11 to form Pt/HZSM-11.

2. The method of claim 1 , wherein the aluminum source comprises aluminum nitrate.

3. The method of claim 1 , wherein the hydroxide comprises sodium hydroxide.

4. The method of claim 1 , wherein the silica source comprises tetraethylorthosilicate (TEOS).

5. The method of claim 1 , wherein adding the silica source to the first solution is performed dropwise.

6. The method of claim 1 , wherein adding the second solution to the fourth solution is performed dropwise.

7. The method of claim 1 , wherein adding the third solution to the fifth solution is performed under vigorous stirring.

8. The method of claim 1 , wherein crystallizing the sixth solution comprises:
placing the sixth solution in an autoclave;
agitating the autoclave; and
heating the autoclave to about 170° C. for about 6 days.

9. The method of claim 8 , wherein recovering the solid product comprises a vacuum filtration process to isolate the solid product from liquids.

10. The method of claim 9 , wherein the solid product is washed by:
flowing water through the solid product to form a filtrate;
testing an aliquot of the filtrate with silver nitrate to determine if a precipitant forms; and
flowing further aliquots of water through the solid product until no precipitant is detected by reaction with silver nitrate.

11. The method of claim 1 , comprising drying the solid product by heating the solid product to between about 90° C. about 110° C. for about 12 hours.

12. The method of claim 1 , wherein calcining the solid product to form the Pt/NaZSM-11 comprises:
ramping a temperature of the solid product to about 550° C.; and
holding the temperature of the solid product at about 550° C. for about 8 hours.

13. The method of claim 12 , wherein the temperature of the solid product is ramped to about 550° C. at about 1° C./min.

14. The method of claim 1 , wherein performing the ammonium ion exchange comprises:
placing the Pt/NaZSM-11 in an aqueous ammonia solution for about 2 hours at a temperature of between about 80° C. and about 100° C. to form Pt/NH 4 ZSM-11;
removing the Pt/NH 4 ZSM-11 from the aqueous ammonia solution;
rinsing the Pt/NH 4 ZSM-11;
placing the Pt/NH 4 ZSM-11 in an aqueous ammonia solution for about two hours at a temperature of between about 80° C. and about 100° C.;
removing the Pt/NH 4 ZSM-11 from the aqueous ammonia solution; and
rinsing the Pt/NH 4 ZSM-11.

15. The method of claim 14 , comprising drying the Pt/NH 4 ZSM-11 by heating the Pt/NH 4 ZSM-11 to between about 90° C. about 110° C. for about 12 hours.

16. The method of claim 1 , wherein calcining the Pt/NH 4 ZSM-11 to form the Pt/NaZSM-11 comprises:
ramping a temperature of the Pt/NH 4 ZSM-11 to about 550° C.; and
holding the temperature of the Pt/NH 4 ZSM-11 at about 550° C. for about 8 hours.

17. The method of claim 16 , wherein the temperature of the Pt/NH 4 ZSM-11 is ramped to about 550° C. at about 1° C./min.

18. The method of claim 1 , wherein the PtHZSM-11 comprises between about 0.2 weight percent platinum and about 1 weight percent platinum.

19. The method of claim 1 , wherein the PtHZSM-11 comprises a surface area of between about 100 m2/g and about 500 m2/g.

20. The method of claim 1 , wherein the PtHZSM-11 comprises a pore volume of between about 0.05 mL/g and about 0.4 mL/g.

Assignees

• Saudi Arabian Oil Co

Inventors

• Alsewdan Donya
• Ding Lianhui
• Al-Eid Manal

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J29/42

  containing iron group metals, noble metals or copper · CPC title

• B01J37/009

  Preparation by separation, e.g. by filtration, decantation, screening · CPC title

• B01J29/064

  containing iron group metals, noble metals or copper · CPC title