Manganese-mediated redox processes for environmental contaminant remediation

• US 8,556,537 B2
• Filed: 02/24/2010
• Issued: 10/15/2013
• Est. Priority Date: 02/24/2009
• Status: Active Grant

• Current Assignee: Geo-Cleanse International Incorporated
• Original Assignee: Geo-Cleanse International Incorporated
• Inventors: Bryant, James Daniel
• Primary Examiner(s): KRECK, JOHN J
• Application Number:
  US12/711,940
• Publication Number:
  US 20100215437A1
• Time in Patent Office: 1,329 Days
• Field of Search: 405/128.1, 405/128.75
• US Class Current: 405/128.75
• CPC Class Codes: B09C 1/002 involving in-situ ground water treatment
• CPC Class Codes: B09C 1/08 chemically
• CPC Class Codes: C02F 1/66 by neutralisation; pH adjustment for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58
• CPC Class Codes: C02F 1/722 Oxidation by peroxides
• CPC Class Codes: C02F 1/725 by catalytic oxidation
• CPC Class Codes: C02F 2101/306 Pesticides
• CPC Class Codes: C02F 2101/36 containing halogen
• CPC Class Codes: C02F 2101/363 PCB's; PCP's
• CPC Class Codes: C02F 2103/06 Contaminated groundwater or leachate

Abstract

Methods and compositions for the remediation of environmental contaminants using redox reactions are described. The redox reactions include manganese compounds and peroxide generating compounds. The methods and compositions are also useful for the remediation of highly oxidized environmental contaminants.

Claims

1. A process for remediation of a site having one or more soil contaminants, one or more groundwater contaminants, or a combination thereof, the process comprising the steps of contacting the site with (a) Mn(IV) or a composition capable of generating Mn(IV), and generating Mn(IV);

(b) a buffered aqueous solution having a pH in the range from about 6 to about 10; and

(c) a peroxide or a compound capable of forming a peroxide.

2. The process of claim 1 wherein the pH is in the range from about 6.5 to about 8.

3. The process of claim 1 wherein the buffered aqueous solution further comprises one or more compounds capable of forming a ligand with manganese.

4. The process of claim 1 wherein the buffered aqueous solution comprises one or more phosphate salts.

5. The process of claim 1 wherein the compound capable of generating Mn(IV) comprises a permanganate compound.

6. The process of claim 1 wherein the Mn(IV) is in the form of a MnO₂ precipitate.

7. The process of claim 1 wherein the peroxide or the compound capable of forming the peroxide comprises hydrogen peroxide.

8. The process of claim 1 wherein the peroxide or the compound capable of forming the peroxide comprises calcium peroxide, magnesium peroxide, sodium percarbonate, or a combination thereof.

9. The process of claim 1 wherein the contaminants comprise a compound capable of reacting with a reducing agent but not an oxidizing agent.

10. The process of claim 1 wherein the contaminants comprise a highly oxidized carbon compound.

11. The process of claim 1 wherein the contaminants comprise a compound capable of reacting with a reductive radical compound.

12. The process of claim 11 wherein the reductive radical compound is superoxide.

13. The process of claim 1 wherein the contaminants comprise one or more chloromethanes, nitroaromatics, or a combination thereof.

14. The process of claim 1 wherein the contaminants comprise one or more components selected from the group consisting of carbon tetrachloride, chloroform, methylene chloride, acetone, freons, nitrobenzenes, hexavalent chromium, and cyanide.

15. The process of claim 1 wherein the contaminants comprise a compound oxidizable by the compound capable of generating Mn(IV).

16. The process of claim 1 wherein the contaminants comprise one or more components selected from the group consisting of tetrachloroethene, trichloroethene, dichloroethylene, vinyl chloride, ethylene dibromide, polychlorinated biphenyls, and naphthalene.

17. The process of claim 1 wherein the contaminants comprise one or more compounds selected from the group consisting of benzene, toluene, xylene, ethylbenzene, chlorobenzene, naphthalene, trinitrotoluene, benzo(a)pyrene, anilines, chlorophenols, methyl tert-butyl ether, tert-butyl alcohol, alkenes, alkanes, perchloroethylene, trichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, carbon disulfide, quinones, hydroquinones, formate, and organic acids.

18. The process of claim 1 wherein the contaminants comprise a pesticide.

19. The process of claim 1 wherein steps (b) and (c) are performed contemporaneously or simultaneously.

20. A process for remediation of a site having one or more soil contaminants, one or more groundwater contaminants, or a combination thereof, the process comprising the steps of contacting the site with (a) Mn(IV) or a compound capable of generating Mn(IV), and generating Mn(IV);

(b) one or more compounds capable of forming a ligand with a manganese ion; and

(c) a peroxide or a compound capable of forming a peroxide.

21. The process of claim 20 wherein the one or more compounds capable of forming a ligand with the manganese ion are included in a buffered aqueous solution having a pH in the range from about 6 to about 10.

22. The process of claim 21 wherein the pH is in the range from about 6.5 to about 8.