Claims
- 1. A process for treating contaminated water, containing contaminants, selected from the group consisting of phosphate and chromate ions, comprising the passage of said contaminated water through an ion exchange bed comprising a chemically stable polymer matrix having an electrically neutral chelating functional group with donor atoms from the group consisting of oxygen atoms and nitrogen atoms, and a Lewis-acid type metal cation bonded to the chelating functional group in a manner that the positive charges of the metal cation are not neutralized, whereby said contaminants are removed from the water.
- 2. The process according to claim 1 in which the chemically stable polymer matrix is a styrene-divinylbenzene copolymer.
- 3. The process according to claim 1 in which the chemically stable polymer matrix is a polymethacrylate.
- 4. The process according to claim 1 in which the donor atoms are nitrogen atoms derived from bis-picolylamine functional groups.
- 5. The process according to claim 1 in which the donor atoms are nitrogen atoms derived from polyimine functional groups.
- 6. The process according to claim 1 in which the Lewis-acid type metal cation is copper.
- 7. The process according to claim 1 in which the contaminated water contains phosphate ions.
- 8. The process according to claim 1 in which the contaminated water contains chromate ions.
- 9. The process according to claim 1 in which the passage of contaminated water through the ion exchange bed is interrupted upon exhaustion of the bed's ion exchange capacity, and during the interruption, the bed is regenerated with a regenerant from the group consisting of sodium chloride and sodium bicarbonate.
- 10. A process for selectively removing anions from contaminated water, the anions being from the group consisting of phosphate anions and chromate anions, wherein the contaminated water also contains a predominant competing anion, comprising the steps of:
- obtaining an ion exchange resin comprising a chemically stable polymer matrix having an electrically neutral chelating functional group with donor atoms from the group consisting of oxygen atoms and nitrogen atoms;
- loading the ion exchange resin with copper by saturating it with a solution of a cupric salt in which the anion of the cupric salt is the same as said predominant competing anion; and
- passing the contaminated water through an ion exchange bed comprising the copper-loaded ion exchange resin.
- 11. The process according to claim 10 in which the predominant competing anion is sulfate and the cupric salt is cupric sulfate.
- 12. The process according to claim 10 in which the predominant competing anion is chloride and the cupric salt is cupric chloride.
CROSS-REFERENCE TO RELATES APPLICATION
This application claims the benefit of provisional application 60/069,139, filed Dec. 8, 1997.
US Referenced Citations (12)
Non-Patent Literature Citations (1)
Entry |
Ramana, A. et al., "Removing Selenium(IV) and Arsenic(V) Oxyanions with Tailored Chelating Polymers", J. Environ. Eng., Sep. 1992, 118(5), 755-775. |