Manufacture of particulate reference materials

Patent metadata

Field	Value
Publication number	US-12165778-B2
Application number	US-202218079923-A
Country	US
Kind code	B2
Filing date	Dec 13, 2022
Priority date	May 13, 2020
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

Methods for forming particulates that are highly consistent with regard to shape, size, and content are described. Particulates are suitable for use as reference materials. Methods can incorporate actinides and/or lanthanides, e.g., uranium, and can be used for forming certified reference materials for use in the nuclear industry. Methods include formation of an aerosol from an oxalate salt solution, in-line diagnostics, and collection of particles of the aerosol either in a liquid impinger or on a solid surface.

First claim

What is claimed is:

1. A method for forming a particulate comprising:
forming a solution comprising an oxalate salt of an actinide and/or a lanthanide;
forming an aerosol comprising the solution, the aerosol comprising particles including the oxalate salt of the actinide and/or the lanthanide;
impinging the aerosol into a liquid collection media and thereby collecting a particulate carried in the aerosol in the liquid collection media, the liquid collection media comprising a viscosity of about 0.9 centipoise or greater at 20° C. and comprising a vapor pressure of about 200 Pascal or less at 20° C.; wherein
the particulate has an average particle size of about 20 micrometers or less and a geometric standard deviation of about 1.25 or less.

2. The method of claim 1 , further comprising carrying out an in-line diagnostic procedure on the aerosol prior to impinging the aerosol into the liquid collection media.

3. The method of claim 2 , the in-line diagnostic procedure comprising aerodynamic particle sizing.

4. The method of claim 1 , the solution comprising an oxalate salt of uranium.

5. The method of claim 1 , the solution comprising an oxalate salt comprising two or more actinides and/or lanthanides.

6. The method of claim 1 , the liquid collection media comprising an alkane comprising 10 or more carbons.

7. The method of claim 6 , the liquid collection media comprising decane.

8. The method of claim 1 , wherein the particulate is collected at a rate of about 0.01 milligram per hour or greater.

9. The method of claim 1 , the solution comprising a first metal element and a second metal element, at least one of the first and second metal elements comprising the actinide and/or the lanthanide, the solution comprising the first and second metallic elements at a molar ratio of the first metal element to the second metal element of from 10:1 to 1000:1.

10. The method of claim 1 , the solution comprising the oxalate salt of the actinide and/or the lanthanide with a known isotopic content.

11. The method of claim 1 , the method forming from about 0.5 milligrams to about 2 milligrams of particles in a period of from about 50 hours to about 100 hours.

12. The method of claim 1 , the particulate having an average particle diameter maxima of about 5 micrometers or less.

13. The method of claim 12 , the particulate having a geometric standard deviation of about 1.2 or less.

14. The method of claim 1 , wherein the aerosol is formed by use of a flow-focusing monodisperse aerosol generator.

15. A microanalytical test specimen comprising:
a substrate comprising a conductive material on a surface and a particulate deposited on the surface, the particulate comprising a metal element, the particulate having an average particle size of about 20 micrometers or less and a geometric standard deviation of about 1.25 or less.

16. The microanalytical test specimen of claim 15 , the metal element is uranium.

17. The microanalytical test specimen of claim 16 , the particulate further comprising a second metal element.

18. The microanalytical test specimen of claim 15 , the surface comprising doped silicon or graphite.

Assignees

• Battelle Savannah River Alliance Llc

Inventors

• Wellons Matthew S
• Devore Ii Michael A
• Kuhne Wendy W

Classifications

• B22F2301/45

  Rare earth metals, i.e. Sc, Y, Lanthanides (57-71) · CPC title

• B22F2202/06

  Use of electric fields · CPC title

• B05D1/06

  Applying particulate materials · CPC title

• C23C24/00

  Coating starting from inorganic powder (spraying of the coating material in molten state C23C4/00; solid state diffusion C23C8/00 - C23C12/00) · CPC title

• Y10T428/12063

  Nonparticulate metal component · CPC title