High temperature layered mixed-metal oxide materials with enhanced stability

Patent metadata

Field	Value
Publication number	US-2017266642-A1
Application number	US-201715453056-A
Country	US
Kind code	A1
Filing date	Mar 8, 2017
Priority date	Mar 17, 2016
Publication date	Sep 21, 2017
Grant date	—

Abstract

Embodiments of the present disclosure are directed towards methods for preparing mixed-metal oxide particles by heating adamantane-intercalated layered double-hydroxide (LDH) particles at a reaction temperature of from 400° C. to 800° C. to form mixed-metal oxide particles. The adamantane-intercalated LDH particles have a general formula [M 1-x Al x (OH) 2 ](A) x .mH 2 O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate, and an aspect ratio greater than 100. The aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle. The mixed-metal oxide particles comprise a mixed-metal oxide phase containing M, Al or Fe, and carbon.

First claim

What is claimed is:

1 . A method for preparing mixed-metal oxide particles comprising:
heating adamantane-intercalated layered double-hydroxide (LDH) particles up to a reaction temperature of from 400° C. to 800° C. to form mixed-metal oxide particles,
where:
the adamantane-intercalated LDH particles have
a length and a width;
a general formula [M 1-x Al x (OH) 2 ](A) x .mH 2 O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate; and
an aspect ratio greater than 100 where the aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle; and

the mixed-metal oxide particles comprise a mixed-metal oxide phase containing M, Al or Fe, and carbon.

2 . The method of claim 1 where the mixed-metal oxide particles further comprise an oxide phase having a formula MO.

3 . The method of claim 1 where the mixed-metal oxide particles comprises less than 5 wt %, by weight of the mixed-metal oxide particles, of spinel-phases having a formula MAl 2 O 4 or MFe 2 O 4 .

4 . The method of claim 1 where the mixed-metal oxide particles do not include any spinel-phases having a formula MAl 2 O 4 or MFe 2 O 4 .

5 . The method of claim 1 where the mixed-metal oxide particles consist essentially of the mixed-metal oxide phase and an oxide phase having a formula MO, and the mixed-metal oxide particles do not include any spinel-phase having a formula MAl 2 O 4 or MFe 2 O 4 .

6 . The method of claim 4 where the mixed-metal oxide phase is positioned between chains of the oxide phase.

7 . The method of claim 1 where the heating up to the reaction temperature is at a heating rate of 4 to 6° C./min.

8 . The method of claim 7 where the heating involves holding at the reaction temperature for at least 4 hours.

9 . The method of claim 1 where the heating of the adamantane-intercalated layered double-hydroxide (LDH) particles is from an initial temperature of 20° C. to 30° C. to the reaction temperature of 400° C. to 800° C.

10 . The method of claim 7 , where M is Mg.

11 . Mixed-metal oxide particles comprising:
at least one mixed-metal oxide phase containing M, Al, and carbon, where M is chosen from Mg, Ca, Co, Ni, Cu, or Zn; and at least one oxide phase having a formula MO, where the mixed-metal oxide phase is sandwiched between chains of the oxide phase, where the mixed-metal oxide particles comprises less than 5 wt %, by weight of the mixed-metal oxide particles, of spinel-phases having a formula MAl 2 O 4 or MFe 2 O 4 .

12 . The mixed-metal oxide particles of claim 11 where the mixed-metal oxide particles do not include any spinel-phase having a formula MAl 2 O 4 or MFe 2 O 4 .

13 . The mixed-metal oxide particles of claim 11 where the mixed-metal oxide particles define a Powder X-Ray Diffraction (PXRD) profile having a signature peak at 13.0+/−0.5 at 800° C.

14 . The mixed-metal oxide particles of claim 11 where the mixed-metal oxide particles consist essentially of the layers of the mixed-metal oxide phase and the oxide phase.

15 . The mixed-metal oxide particles of claim 11 where M is Mg.

16 . A method of removing constituents from a process stream comprising:
contacting the process stream with a catalyst, where the catalyst comprises mixed-metal oxide particles comprising:
at least one mixed-metal oxide phase containing M, Al, and carbon, where M is chosen from Mg, Ca, Co, Ni, Cu, or Zn; and
at least one oxide phase having a formula MO, where the mixed-metal oxide phase is sandwiched between chains of the oxide phase, and where the mixed-metal oxide particles do not include any spinel-phase having a formula MAl 2 O 4 or MFe 2 O 4 .

17 . The method of claim 16 where M is Mg.

18 . The method of claim 16 where the process stream is a gas stream and the removed constituent is carbon dioxide.

19 . The method of claim 16 where the process stream is a gas stream or a water stream and the removed constituent is a toxic ion.

20 . The method of claim 19 where the toxic ion is one or more of a phosphate, arsenate, chromate, bromide, iodide, and sulfide.

Assignees

• Saudi Arabian Oil Co
• Univ Durham

Inventors

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

Classifications

• C01P2002/22

  layered hydroxide-type, e.g. of the hydrotalcite-type · CPC title

• B01D2257/55

  Compounds of silicon, phosphorus, germanium or arsenic · CPC title

• B01D53/8671

  Removing components of defined structure not provided for in B01D53/8603 - B01D53/8668 · CPC title

• B01J23/002

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

• B01D2255/20753

  Nickel · CPC title