Methods for preparing mixed-metal oxide diamondoid nanocomposites and catalytic systems including the nanocomposites

Patent metadata

Field	Value
Publication number	US-11351604-B2
Application number	US-202017101282-A
Country	US
Kind code	B2
Filing date	Nov 23, 2020
Priority date	May 19, 2017
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

Methods for preparing a layered metal nanocomposite and a layered metal nanocomposite. The method includes mixing a magnesium salt and an aluminum salt to form a Mg2+/Al3+ solution. The Mg/Al has a molar ratio of between 0.5:1 to 6:1. Then a diamondoid compound is added to the Mg2+/Al3+ solution to form a reactant mixture. The diamondoid compound has at least one carboxylic acid moiety. The reactant mixture is heated at a reaction temperature for a reaction time to form a Mg/Al-diamondoid intercalated layered double hydroxide. The Mg/Al-diamondoid intercalated layered double hydroxide is thermally decomposed under a reducing atmosphere for a decomposition time at a decomposition temperature to form the layered metal nanocomposite.

First claim

The invention claimed is:

1. A layered metal nanocomposite prepared by:
mixing a magnesium salt and an aluminum salt to form a Mg 2+ /Al 3+ solution, in which the Mg/Al has a molar ratio of between 0.5:1 to 6:1;
adding a diamondoid compound to the Mg 2+ /Al 3+ solution to form a reactant mixture, in which the diamondoid compound has at least one carboxylic acid moiety;
heating the reactant mixture at a reaction temperature for a reaction time to form a Mg/Al-diamondoid intercalated layered double hydroxide; and
thermally decomposing the Mg/Al-diamondoid intercalated layered double hydroxide under a reducing atmosphere for a decomposition time at a decomposition temperature to form the layered metal nanocomposite.

2. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises 50 wt. % to 90 wt. % MgO particles and from 10 wt. % to 50 wt. % adamantane-derived carbon, based on the total weight of the layered metal nanocomposite.

3. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having multiple basal reflections at 2θ values lower than 42.71°.

4. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at a 2θ value of approximately 6.61°.

5. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at a 2θ value of approximately 7.98°.

6. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at a 2θ value of approximately 9.23°.

7. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at a 2θ value of approximately 11.49°.

8. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at 2θ values of approximately 6.61°, approximately 7.98°, approximately 9.23°, and approximately 11.49°.

9. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises mixed metal oxides and fibrous or rod shaped diamondoids.

10. The layered metal nanocomposite of claim 9 , in which the fibrous or rod shaped diamondoids comprise a length of 2 or more micrometers and a diameter of 2 to 5 nanometers.

11. The layered metal nanocomposite claim 1 , in which the magnesium salt is Mg(OH) 2 and the aluminum salt is Al(OH) 3 .

12. The layered metal nanocomposite of claim 1 , in which the diamondoid compound is 1-adamantane carboxylic acid.

13. The layered metal nanocomposite of claim 1 , in which the reducing atmosphere comprises hydrogen gas.

14. The layered metal nanocomposite of claim 1 , in which the layered metal nanocomposite comprises a layered morphology of a plurality of octahedral and tetrahedral environments.

15. A catalyst system comprising:
a layered metal nanocomposite prepared by:
mixing a magnesium salt and an aluminum salt to form a Mg 2+ /Al 3+ solution, in which the Mg/Al has a molar ratio of between 0.5:1 to 6:1;
adding a diamondoid compound to the Mg 2+ /Al 3+ solution to form a reactant mixture, in which the diamondoid compound has at least one carboxylic acid moiety;
heating the reactant mixture at a reaction temperature for a reaction time to form a Mg/Al-diamondoid intercalated layered double hydroxide; and
thermally decomposing the Mg/Al-diamondoid intercalated layered double hydroxide under a reducing atmosphere for a decomposition time at a decomposition temperature to form the layered metal nanocomposite.

16. The catalyst system of claim 15 , in which the layered metal nanocomposite comprises 50 wt. % to 90 wt. % MgO particles and from 10 wt. % to 50 wt. % adamantane-derived carbon, based on the total weight of the layered metal nanocomposite.

17. The catalyst system of claim 15 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having multiple basal reflections at 2θ values lower than 42.71°.

18. The catalyst system of claim 15 , in which the layered metal nanocomposite comprises a Powder X-Ray Diffraction (PXRD) pattern having basal reflections at 2θ values of approximately 6.61°, approximately 7.98°, approximately 9.23°, and approximately 11.49°.

19. The catalyst system of claim 15 , in which the layered metal nanocomposite comprises mixed metal oxides and fibrous or rod shaped diamondoids.

20. The catalyst system of claim 15 , in which the fibrous or rod shaped diamondoids comprise a length of 2 or more micrometers and a diameter of 2 to 5 nanometers.

Assignees

• Saudi Arabian Oil Co
• Univ Durham

Inventors

• Veerabhadrappa Manohara Gudiyor
• Greenwell Hugh Christopher
• Whiting Andrew
• Hall John Adrian
• Alabedi Gasan

Classifications

• B22F1/17 Primary

  Metallic particles coated with metal · CPC title

• B01J35/30

  characterised by their physical properties · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · 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