METHODS OF PRODUCING MOLYBDENUM DISULFIDE POWDERS

• US 20140308443A1
• Filed: 06/25/2014
• Published: 10/16/2014
• Est. Priority Date: 02/04/2011
• Status: Active Grant

• Current Assignee: Climax Molybdenum Company (Freeport-Mcmoran Copper & Gold Incorporated)
• Original Assignee: Climax Molybdenum Company (Freeport-Mcmoran Copper & Gold Incorporated)
• Inventors: Logue, Gregory Rue, Giannotti, Larry, Cole, James A., Cottrell, David L., de Gala, Gary G.
• Granted Patent: US 9,878,332 B2
• Time in Patent Office: Days
• US Class Current: 427/220
• CPC Class Codes: B02C 19/06 Jet mills
• CPC Class Codes: B02C 19/068 of the fluidised-bed type
• CPC Class Codes: B02C 23/02 Feeding devices for grain mills B02C11/04; for roller mills B02C4/286; transport devices in general B65G
• CPC Class Codes: C01G 39/06 Sulfides
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2006/19 Oil-absorption capacity, e.g. DBP values
• CPC Class Codes: Y02P 10/20 Recycling
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A method of producing powder product includes the steps of: Feeding a precursor powder material into a jet mill; feeding a gas into the jet mill to initiate a jet milling operation to produce size-reduced particles; and coating size-reduced particles with oil so that newly exposed surfaces of size-reduced particles are coated with oil, wherein the coating step includes one or more of a post-milling oil injection process and a pre-milling oil injection process.

Claims

1. A method of producing a powder product comprising:

feeding a precursor powder material into a jet mill;

feeding a gas into the jet mill to initiate a jet milling operation to produce size-reduced particles; and

coating size-reduced particles with oil so that newly exposed surfaces of size-reduced particles are coated with oil, wherein said coating comprises one or more selected from the group consisting of a post-milling oil injection process and a pre-milling oil injection process.

2. The method of claim 1, wherein said feeding a precursor powder material comprises feeding a molybdenum disulfide precursor powder material to produce a molybdenum disulfide powder product.

3. The method of claim 2, wherein said post-milling oil injection process comprises:

withdrawing size-reduced particles from the jet mill as a particle-laden product stream; and

combining the particle-laden product stream with an atomized stream of oil so that newly exposed surfaces of the size-reduced particles are coated with oil.

4. The method of claim 2, wherein said pre-milling oil injection process comprises injecting oil into the jet mill during the jet milling operation.

5. The method of claim 4, wherein injecting oil into the jet mill comprises combining oil with a flow of wall gas and injecting the combined oil and wall gas into the jet mill.

6. The method of claim 2, wherein said molybdenum disulfide precursor powder material comprises a technical grade of molybdenum disulfide powder.

7. The method of claim 2, wherein said molybdenum disulfide powder product comprises an acid number of less than about 0.3 mg KOH/g.

8. The method of claim 2, wherein said molybdenum disulfide powder product comprises an acid number in a range of about 0.1 mg KOH/g to about 0.35 mg KOH/g.

9. The method of claim 2, further comprising conducting the jet milling operation until said molybdenum disulfide powder product comprises a D50 particle size of less than 4 μ

m.

10. The method of claim 2, further comprising conducting the jet milling operation until said molybdenum disulfide powder product comprises a D50 particle size in a range of about 0.9 μ

m to about 1.6 μ

m.

11. The method of claim 2, wherein said oil comprises a paraffinic oil.

12. The method of claim 11, wherein said paraffinic oil comprises polymethylmethacrylate.

13. The method of claim 12, wherein said paraffinic oil comprises a silicone anti-foaming compound.

14. The method of claim 12, wherein said paraffinic oil comprises a fatty-acid ester friction modifying compound.

15. A method of producing a powder product, comprising:

providing a supply of a precursor powder material;

accelerating particles of the precursor powder material by combining them with a flow of gas;

confining the accelerated particles in a milling chamber so that they collide with one another to effect a size reduction;

withdrawing size-reduced particles from the milling chamber as a particle-laden product stream; and

combining the particle-laden product stream with an atomized stream of oil so that newly exposed surfaces of size-reduced particles are coated with oil.

16. The method of claim 15, wherein providing a supply of a precursor powder material comprises providing a supply of molybdenum disulfide precursor powder material to produce a molybdenum disulfide powder product.

17. A method of producing a powder product, comprising:

providing a supply of a precursor powder material;

accelerating particles of the precursor powder material by combining them with a flow of gas;

confining the accelerated particles in a milling chamber so that they collide with one another to effect a size reduction; and

injecting oil into the milling chamber.

18. The method of claim 17, wherein injecting oil into the milling chamber comprises combining oil with a flow of wall gas and injecting the combined oil and wall gas into the milling chamber.

19. The method of claim 17, wherein injecting oil into the milling chamber comprises combining oil with the flow of gas before using the flow of gas to accelerate the particles of the precursor material.

20. The method of claim 17, wherein providing a supply of a precursor powder material comprises providing a supply of molybdenum disulfide precursor powder material to produce a molybdenum disulfide powder product.