CERIUM CONTAINING NANOPARTICLES PREPARED IN NON-POLAR SOLVENT

• US 20120117863A1
• Filed: 11/14/2011
• Published: 05/17/2012
• Est. Priority Date: 11/12/2010
• Status: Active Grant

• Current Assignee: Cerion, LLC (Revstone Industries LLC)
• Original Assignee: Cerion Technology, Inc.
• Inventors: Hailstone, Richard Kenneth, COWDERY-CORVAN, Peter Jerome, Irving, Lyn Marie, Reed, Kenneth Joseph, Allston, Thomas Dale, Augustyn, Carly Louise
• Granted Patent: US 8,980,202 B2
• Time in Patent Office: Days
• US Class Current: 44/530
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01F 17/235 Cerium oxides or hydroxides
• CPC Class Codes: C01F 17/32 oxide or hydroxide being the only anion, e.g. NaCeO2 or MgxCayEuO
• CPC Class Codes: C01G 25/00 Compounds of zirconium
• CPC Class Codes: C01G 49/0054 containing one rare earth metal, yttrium or scandium
• CPC Class Codes: C01P 2002/54 one element only
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer

Abstract

A method of making cerium-containing metal oxide nanoparticles in non-polar solvent eliminates the need for solvent shifting steps. The direct synthesis method involves: (a) forming a reaction mixture of a source of cerous ion and a carboxylic acid, and optionally, a hydrocarbon solvent; and optionally further comprises a non-cerous metal ion; (b) heating the reaction mixture to oxidize cerous ion to ceric ion; and (c) recovering a nanoparticle of either cerium oxide or a mixed metal oxide comprising cerium. The cerium-containing oxide nanoparticles thus obtained have cubic fluorite crystal structure and a geometric diameter in the range of about 1 nanometer to about 20 nanometers. Dispersions of cerium-containing oxide nanoparticles prepared by this method can be used as a component of a fuel or lubricant additive.

Claims

1. A method of making a cerium-containing metal oxide nanoparticle, comprising:

a) forming a reaction mixture of a source of cerous ion and a solvent, and optionally further comprising a non-cerous metal ion, wherein the solvent consists essentially of;

(1) a carboxylic acid, and (2) an optional hydrocarbon;

b) heating the reaction mixture; and

,

c) recovering a cerium-containing metal oxide nanoparticle.

2. The method of claim 1, wherein said cerium-containing metal oxide nanoparticle is of cubic fluorite crystal structure and has a geometric diameter of about 1 nanometer to about 20 nanometers.

3. The method of claim 1, wherein said non-cerous metal ion (M) is iron, zirconium, or a combination thereof.

4. The method of claim 1, wherein said carboxylic acid is a C₃-C₂₂ paraffinic or olefinic carboxylic acid.

5. The method of claim 4, wherein said paraffinic carboxylic acid is octanoic acid.

6. The method of claim 4, wherein said olefinic carboxylic acid is oleic acid.

7. The method of claim 1, wherein said carboxylic acid surfactant is a monoether carboxylic acid.

8. The method of claim 7, wherein said monoether carboxylic acid is methoxyacetic.

9. The method of claim 1, wherein said carboxylic acid surfactant is a polyether carboxylic acid.

10. The method of claim 9, wherein said polyether carboxylic acid is 2-(2-methoxyethoxy)acetic acid or 2-[2-(2-methoxyethoxy)ethoxy]acetic acid.

11. The method of claim 1, wherein said hydrocarbon solvent is a C₅-C₂₅ paraffin, an olefin, an isoparaffin distillate, or a hydrotreated petroleum distillate.

12. The method of claim 11, wherein said paraffin is a straight chain, a branched or a cyclic paraffin.

13. The method of claim 11, wherein said olefin is 1-octadecene.

14. The method of claim 1, wherein the reaction mixture is heated from about 100°

C. to about 250°

C.

16. The method of claim 14, wherein said non-cerous metal ion is iron and/or zirconium.

17. The method of claim 14, wherein said carboxylic acid is a C₃-C₂₂ paraffinic or olefinic carboxylic acid.

18. The method of claim 14, wherein said carboxylic acid is selected from the group consisting of:

octanoic acid, oleic acid, methoxyacetic acid, 2-(2-methoxyethoxy)acetic acid, and 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, and mixtures thereof.

19. The method of claim 14, wherein said hydrocarbon solvent is a C₅-C₂₅ paraffin, an olefin, an isoparaffin distillate, or a hydrotreated petroleum distillate.

20. The method of claim 19, wherein said olefin is 1-octadecene.

15. A method of making cerium-containing metal oxide nanoparticles, comprising:

a) forming a reaction mixture comprising a source of cerous ion, an optional source of one or more non-cerous metal ions (M), and a solvent consisting essentially of a carboxylic acid, and, optionally, a hydrocarbon; and

b) heating the reaction mixture to oxidize cerous ion to eerie ion; and

c) collecting a cubic fluorite crystalline nanoparticle of cerium oxide, CeO_2-δ

, or mixed metal oxide, Ce<sub>1−

x</sub>M_xO<sub>2−

δ</sub>

, wherein x is about 0.001 to about 0.95, and δ

is about 0.0 to about 0.5.