Method of making and using nanoscale metal

• US 6,777,449 B2
• Filed: 12/19/2001
• Issued: 08/17/2004
• Est. Priority Date: 12/21/2000
• Status: Expired due to Fees

• Current Assignee: Arcadis US Incorporated (Arcadis N.V.)
• Original Assignee: Case Logic (Thule Group AB)
• Inventors: Suthersan, Suthan S., Vance, David, Palmer, Peter
• Primary Examiner(s): Metzmaier, Daniel S.
• Application Number:
  US10/026,329
• Publication Number:
  US 20020151602A1
• Time in Patent Office: 972 Days
• Field of Search: 516/33, 516/354, 516/35, 241/16, 241/21, 502/151, 502/159, 502/172
• US Class Current: 516/35
• CPC Class Codes: B01J 13/0043 containing elemental metal for medical or diagnostical purposes A61K, G01N
• CPC Class Codes: B09C 1/002 involving in-situ ground water treatment
• CPC Class Codes: B09C 1/08 chemically

Abstract

When elemental iron is in the presence of chlorinated compounds (contaminants) a naturally occurring reaction takes place and the chlorinated compounds are reduced and form harmless compounds. The production of extremely small metal particles containing elemental iron or a mixture of elemental iron and a second metal is imperative to this method of treating contaminants and is the subject of the present invention. When the particle is made small enough a surfactant is not required for the particle to do its job. The elemental metal may be kept in an elemental state by keeping it in an oxygen-scavenging environment. This is achieved by either suspending the nanoscale metal in a carbohydrate solution or by injecting a carbohydrate solution in atomized form into the gas used to inject the metal into the subsurface soil. Additionally, the present invention is to a method of using elemental metal to reductively dehalogenate halogenated hydrocarbons, to reduce soluble metals and to treat metalloids in subsurface soil.

Claims

1. A method of producing nanoscale metallic colloids comprising the steps of:

a. supplying an elemental metal, wherein the size of said elemental metal is in the range of 1-10 microns;

b. suspending said elemental metal in a non-aqueous organic liquid that is non-reactive to the surface of said elemental metal to form a suspension;

c. adding a dispersant to said suspension;

d. comminuting the suspension containing the dispersant to form a mixture; and

e. agitating the mixture at a rate and time necessary to produce nanoscale metallic colloids, and

f. mixing said nanoscale metallic colloids with a salt solution comprising a second metal.

2. The method of claim 1, wherein said elemental metal is selected from the group consisting of iron, tin, zinc and palladium and mixtures thereof.

3. The method of claim 1, wherein said second metal is selected from the group consisting of platinum, palladium, zinc, nickel and tin and mixtures thereof.

4. The method of claim 1, further comprising the step of drying the nanoscale metallic colloids.

5. The method of claim 1, further comprising the step of storing the nanoscale metallic colloids in an anaerobic solution.

6. The method of claim 1, wherein said nanoscale metallic colloids has a size in the range of 100-400 nanometers.

7. The method of claim 1, wherein said non-aqueous organic liquid is selected from the group consisting of dodecane, butyl acetate and polypropylene glycol ethyl ether acetate and mixtures thereof.

8. The method of claim 1, wherein said comminuting is performed by a method selected from the group consisting of ball milling, rod milling and high speed gas jet agitation.