Bifunctional metal oxides and paraffin isomerization therewith

Patent metadata

Field	Value
Publication number	US-11745168-B2
Application number	US-202117349986-A
Country	US
Kind code	B2
Filing date	Jun 17, 2021
Priority date	Jun 17, 2021
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

Tungstated zirconium catalysts for paraffin isomerization may comprise: a mixed metal oxide that is at least partially crystalline and comprises tungsten, zirconium, and a variable oxidation state metal selected from Fe, Mn, Co, Cu, Ce, Ni, and any combination thereof. The mixed metal oxide comprises about 5 wt. % to about 25 wt. % tungsten, about 40 wt. % to about 70 wt. % zirconium, and about 0.01 wt. % to about 5 wt. % variable oxidation state metal, each based on a total mass of the mixed metal oxide. The mixed metal oxide has a total surface area of about 50 m 2 /g or greater as measured according to ISO 9277, and at least one of the following: an ammonia uptake of about 0.05 to about 0.3 mmol/g as measured by temperature programmed adsorption/desorption, or a collidine uptake of about 100 μmol/g or greater as measured gravimetrically.

First claim

What is claimed is:

1. A composition comprising:
a mixed metal oxide that is at least partially crystalline and comprises tungsten, zirconium, and a variable oxidation state metal;
wherein the variable oxidation state metal comprises a metal selected from the group consisting of Fe, Mn, Co, Cu, Ce, Ni, and any combination thereof;
wherein the mixed metal oxide comprises about 5 wt. % to about 25 wt. % tungsten, about 40 wt. % to about 70 wt. % zirconium, and about 0.01 wt. % to about 2 wt. % variable oxidation state metal, each based on a total mass of the mixed metal oxide; and
wherein the mixed metal oxide has a total surface area of between 50 m 2 /g and 150 m 2 /g as measured according to ISO 9277, and at least one of the following:
an ammonia uptake of about 0.05 to about 0.3 mmol/g as measured by temperature programmed adsorption/desorption, or
a collidine uptake of about 100 μmol/g or greater as measured gravimetrically.

2. The composition of claim 1 , wherein the mixed metal oxide is impregnated with a noble metal, the noble metal being present at about 0.01 wt. % to about 2 wt. % based on total mass of the mixed metal oxide plus noble metal.

3. The composition of claim 2 , wherein the noble metal comprises at least one noble metal selected from the group consisting of Pt, Pd, Rh, and any combination thereof.

4. The composition of claim 2 , wherein the mixed metal oxide, when activated, is effective to isomerize n-heptane at a conversion:cracking yield ratio of about 10 or greater at about 10% or less cracking yield.

5. The composition of claim 1 , wherein the mixed metal oxide has a total surface area ranging from about 60 m 2 /g to about 130 m 2 /g.

6. The composition of claim 1 , wherein the mixed metal oxide has a tungsten surface density, measured as W atoms/nm 2 , ranging from about 2 to about 20.

7. The composition of claim 1 , wherein the mixed metal oxide has an X-ray powder diffraction peak height ratio ranging from 0 to about 5 for monoclinic tungsten oxide (m-WO 3 ) relative to monoclinic zirconium oxide (m-ZrO 2 ).

8. The composition of claim 1 , wherein the mixed metal oxide comprises about 9 wt. % to about 20 wt. % tungsten, about 40 wt. % to 70 wt. % Zr, and about 0.01 wt. % to 2 wt. % variable oxidation state metal, each based on total mass of the mixed metal oxide.

9. The composition of claim 8 , wherein the mixed metal oxide comprises about 0.5 wt. % to 0.7 wt. % variable oxidation state metal, based on total mass of the mixed metal oxide.

10. The composition of claim 8 , wherein the variable oxidation state metal is selected from the group consisting of Fe, Mn, Cu, Ce, and any combination thereof.

11. The composition of claim 1 , wherein the variable oxidation state metal comprises Fe.

12. The composition of claim 1 , further comprising:
a binder combined with the mixed metal oxide.

13. A method comprising:
combining a zirconium source, a tungsten source, and a variable oxidation state metal source in a reaction mixture under alkaline conditions having a pH of about 7.5 or greater;
wherein the variable oxidation state metal comprises a metal selected from the group consisting of Fe, Mn, Co, Cu, Ce, Ni, and any combination thereof;

obtaining under the alkaline conditions a slurry comprising a co-precipitate reaction product formed from the zirconium source, the tungsten source, and the variable oxidation state metal source;
digesting the slurry and forming an amorphous digestion product from the co-precipitate reaction product; and
calcining the amorphous digestion product in air at a temperature ranging from about 700° C. to about 900° C. to obtain a mixed metal oxide that is at least partially crystalline and comprises about 5 wt. % to about 25 wt. % tungsten, about 40 wt. % to about 70 wt. % zirconium, and about 0.01 wt. % to about 2 wt. % variable oxidation state metal, each based on a total mass of the mixed metal oxide;
wherein the mixed metal oxide has a total surface area of about 50 m 2 /g or greater as measured according to ISO 9277, and at least one of the following:
an ammonia uptake of about 0.05 to about 0.3 mmol/g as measured by temperature programmed adsorption/desorption, or
a collidine uptake of about 100 μmol/g or greater as measured gravimetrically.

14. The method of claim 13 , wherein the reaction mixture is formed by combining a first solution comprising the tungsten source, and a second solution comprising the zirconium source and the variable oxidation state metal source in an alkaline solution having a pH of about 9 to about 10.

15. The method of claim 13 , wherein the mixed metal oxide is impregnated with a noble metal, the noble metal being present at about 0.01 wt. % to about 2 wt. %, based on total mass of the mixed metal oxide plus noble metal.

16. The method of claim 13 , further comprising:
after calcining, introducing a noble metal precursor to the mixed metal oxide by incipient wetness impregnation, vacuum infiltration impregnation, or any combination thereof.

17. The method of claim 15 , wherein the noble metal comprises at least one noble metal selected from the group consisting of Pt, Pd, Rh, and any combination thereof.

18. The method of claim 16 , wherein the noble metal precursor comprises a water-soluble metal complex selected from the group consisting of (NH 3 ) 4 Pt(NO 3 ) 2 , (NH 3 ) 4 Pt(OH) 2 , (NH 3 ) 4 PtCl 2 , H 2 PtCl 6 , and any combination thereof.

19. The method of claim 13 , wherein the mixed metal oxide comprises about 9 wt. % to about 20 wt. % tungsten, about 40 wt. % to 70 wt. % Zr, and about 0.01 wt. % to 2 wt. % variable oxidation state metal, each based on total mass of the mixed metal oxide.

20. The method of claim 19 , wherein the mixed metal oxide comprises about 0.5 wt. % to 0.7 wt. % variable oxidation state metal, based on total mass of the mixed metal oxide.

21. The method of claim 13 , wherein the variable oxidation state metal is selected from the group consisting of Fe, Mn, Cu, Ce, and any combination thereof.

22. The method of claim 13 , wherein the variable oxidation state metal comprises Fe.

23. The method of claim 13 , further comprising:
forming an extrudate from the mixed metal oxide.

24. The method of claim 23 , where the mixed metal oxide is co-extruded with a binder to form the extrudate.

25. The method of claim 24 , wherein the binder comprises at least one substance selected from the group consisting of a W/Zr oxide, a W/Zr hydroxide, a W oxide, a W hydroxide, a Zr oxide, a Zr hydroxide, an Fe oxide, an Fe hydroxide, a Ti oxide, a Ti hydroxide, silica, silica alumina, a titania silica, an aluminum oxide, an aluminum hydroxide, and any combination thereof.

26. The method of claim 13 , wherein the mixed metal oxide has an X-ray powder diffraction peak height ratio ranging from 0 to about 5 for monoclinic tungsten oxide (m-WO 3 ) relative to monoclinic zirconium oxide (m-ZrO 2 ).

27. A method comprising:
heating a mixed metal oxide under hydrogen to form an activated catalyst, the mixed metal oxide being at least partially crystalline and comprising about 5 wt. % to about 25 wt. % tungsten, about 40 wt. % to about 70 wt. % zirconium, and about 0.01 wt. % to about 2 wt. % variable oxidation state metal, wherein the mixed metal oxide is further impregnated with about 0.01 wt. % to about 2 wt. % noble metal, each based on a total mass of the mixed metal oxide

Assignees

• Exxonmobil Technology & Engineering Company

Inventors

• Weigel Scott J
• Witzke Megan E
• Sattler Wesley
• Carcuffe Brandon M
• Dakka Jihad M
• Dugan Ryan S

Classifications

• B01J35/615

  100-500 m2/g · CPC title

• B01J23/002 Primary

  Mixed oxides other than spinels, e.g. perovskite · CPC title

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J35/70

  characterised by their crystalline properties, e.g. semi-crystalline (catalysts comprising carbon B01J21/18; molecular sieves B01J29/00) · CPC title

• B01J35/31

  Density · CPC title