Silica particles coated with β-cyclodextrin for the removal of emerging contaminants from wastewater

Patent metadata

Field	Value
Publication number	US-9828458-B2
Application number	US-201214350658-A
Country	US
Kind code	B2
Filing date	Oct 17, 2012
Priority date	Oct 17, 2011
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

Provided is a silica particle coated with β-cyclodextrin, wherein said cyclodextrin is attached to said silica particle via at least one crosslinking agent and/or at least one copolymer. Also provided are methods of removing contaminants from a flowing or stationary liquid phase comprising the step of contacting said liquid phase with the silica particle coated with β-cyclodextrin.

First claim

What is claimed is:

1. Silica particles coated with cross-linked β-cyclodextrin polymer, wherein said cross-linked β-cyclodextrin polymer is the reaction product on silica particles of
(i) β-cyclodextrin and hexamethylene diisocyanate in a molar ratio of β-cyclodextrin:hexamethylene diisocyanate of from about 1:7 to about 1:15, and wherein the molar ratio of β-cyclodextrin incorporated into said cross-linked β-cyclodextrin polymer to silica comprising the coated particles is from about 1:15 to about 1:30; or
(ii) β-cyclodextrin and epichlorohydrin in a molar ratio of β-cyclodextrin:epichlorohydrin of from about 1:7 to about 1:9, and wherein the molar ratio of β-cyclodextrin incorporated into said cross-linked β-cyclodextrin polymer to silica comprising the coated particles is from about 1:83 to about 1:125.

2. The silica particles coated with cross-linked β-cyclodextrin polymer according to claim 1 , wherein said cross-linked β-cyclodextrin polymer is the reaction product of β-cyclodextrin with hexamethylene diisocyanate.

3. The silica particles coated with β-cyclodextrin polymer according to claim 2 wherein the particle size is in the range from about US sieve size 10 to about US sieve size 200.

4. The silica particles coated with β-cyclodextrin polymer according to claim 1 wherein the particle size is in the range from about US sieve size 10 to about US sieve size 200.

5. A method of removing contaminants from a liquid comprising the step of contacting said liquid with the silica particles coated with β-cyclodextrin of claim 2 .

6. The method of claim 5 wherein said contaminant is a steroid hormone.

7. The method of claim 5 wherein said contaminant is a phenol.

8. The method of claim 5 wherein said contaminant is a perfluorocompound.

9. A method of removing contaminants from a liquid comprising the step of contacting said liquid with the silica particles coated with β-cyclodextrin of claim 1 .

10. The method of claim 9 wherein said liquid is flowing.

11. The method of claim 10 wherein said liquid is mixed with said silica particles coated with β-cyclodextrin and said mixture is agitated.

12. The method of claim 9 wherein said silica particles coated with β-cyclodextrin are contained in a column.

13. The method of claim 9 wherein said liquid is stationary.

14. The method of claim 13 wherein said liquid is mixed with said silica particles coated with β-cyclodextrin and said mixture is agitated.

15. The method of claim 9 wherein said contaminant is a steroid hormone.

16. The method of claim 15 wherein said steroid hormone is an estrogen, a progestrogen or a testosterone.

17. The method of claim 16 wherein said steroid hormone is selected from the group consisting of 17β-estradiol, 17α-ethynylestradiol, estriol, 17α-estradiol, trimegestrone, estrone, 17α-dihydroequilin, medrogestone, progesterone, gestodone, norgestrel, equilin, testosterone, desogestrel and etonorgestrel.

18. The method of claim 9 wherein said contaminant is a phenol.

19. The method of claim 18 wherein said phenol is bisphenol A (BPA).

20. The method of claim 9 wherein said contaminant is a perfluorocompound.

21. The method of claim 20 wherein said perfluorocompound is selected from the group consisting of tridecafluorononanoic acid, perfluoroheptanoic acid, undecafluorohexanoic acid, perfluorodecanoic acid, heptafluorooctane salt and perfluorooctanoic acid (PFOA).

22. A process for producing silica particles coated with β-cyclodextrin comprising:
coating silica particles with β-cyclodextrin; and
polymerizing said β-cyclodextrin with hexamethylene diisocyanate in a polymerization reaction to form hexamethylene diisocyanate-crosslinked β-cyclodextrin polymer;
wherein the molar ratio of β-cyclodextrin: hexamethylene diisocyanate in said polymerization reaction is from about 1:7 to about 1:15 and wherein the molar ratio of β-cyclodextrin:silica in said polymerization reaction is from about 1:15 to about 1:30.

23. A process for producing silica particles coated with β-cyclodextrin comprising:
coating silica particles with β-cyclodextrin; and
polymerizing said β-cyclodextrin with epichlorohydrin in a polymerization reaction to form epichlorohydrin-crosslinked β-cyclodextrin polymer;
wherein the molar ratio of β-cyclodextrin: epichlorohydrin in said polymerization reaction is from about 1:7 to about 1:9 and wherein the molar ratio of β-cyclodextrin:silica in said polymerization reaction is from about 1:83 to about 1:125.

Assignees

• Temple University—Of the Commonwealth System of Higher Education

Inventors

• Suri Rominder P S
• Bhattarai Bikash

Classifications

• C02F2101/305

  Endocrine disruptive agents · CPC title

• B01J20/3282

  Crosslinked polymers · CPC title

• B01J20/3293 Primary

  Coatings on a core, the core being particle or fiber shaped, e.g. encapsulated particles, coated fibers · CPC title

• B01J20/267

  Cross-linked polymers · CPC title

• C07H23/00

  Compounds containing boron, silicon or a metal, e.g. chelates or vitamin B12 (esters with inorganic acids C07H11/00) · CPC title