Adsorbent for organic fluoro-compound comprising cyclodextrin-supported polymer
AssigneesDaikin Industries, Ltd., Osaka University
InventorsKenji Adachi, Masaki Kuramitsu, Mitsuru Akashi, Toshiyuki Kida
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Abstract
The present invention is to provide a material that is capable of selectively adsorbing organic fluoro-compounds such as perfluorooctane sulfonic acid, allows the adsorbed organic fluoro-compounds to be recovered, and is reusable as an adsorbent, specifically to provide a polymer in which cyclodextrin is supported on the surface of a water-insoluble polymer, and an adsorbent containing the same, and a method of use of the same as a selective adsorbent of, in particular, an organic fluoro-compound.
Claims6
An adsorbent for an organic fluoro-compound, wherein cyclodextrin is supported on the surface of a water-insoluble polymer,
- wherein the water-insoluble polymer comprises polystyrene particles,
- wherein the polystyrene particles and the cyclodextrin are chemically bonded via a divalent linking group —X— in which
- X is N, O, S, O(CH2)nO, with n being 1 to 6, or
- X is O(CH2CH2O)n, with n being 2 to 6, and
- the hyphen “-” is a single bond;
- and
- wherein the organic fluoro-compound is selected from the group consisting of fluoroalkane carboxylic acids (R—COOH), fluoroalkane sulfonic acids (R—SO3H), fluoroalkyl alcohols (R—(CH2)nOH, with n being 1 to 6, and a mixture thereof, in which R is selected from the group consisting of CF3(CF2)n, with n 0 to 11;
- HCF2(CF2)n with n being 0 to 11;
- CF3(CF2)nO[CF(CF3)CF2O]mCF(CF3), with n being 0 to 5 and m being 0 to 5;
- and (CF3)2CF(CF2)n, with n being 0 to 10.
A method for removal of an organic fluoro-compound, which comprises:
- adsorbing the organic fluoro-compound with an adsorbent from an aqueous solution containing the organic fluoro-compound, wherein the adsorbent comprises cyclodextrin supported on the surface of a water-insoluble polymer,
- wherein the water-insoluble polymer comprises polystyrene particles,
- wherein the polystyrene particles and the cyclodextrin are chemically bonded via a divalent linking group —X— in which
- X is N, O, S, O(CH2)nO, with n being 1 to 6, or
- X is O(CH2CH2O)n, with n being 2 to 6, and
- the hyphen “-” is a single bond;
- and
- wherein the organic fluoro-compound is selected from the group consisting of fluoroalkane carboxylic acids (R—COOH), fluoroalkane sulfonic acids (R—SO3H), fluoroalkyl alcohols (R—(CH2)nOH, with n being 1 to 6, and a mixture thereof, in which R is selected from the group consisting of CF3(CF2)n, with n being 0 to 11;
- HCF2(CF2)n with n being 0 to 11;
- CF3(CF2)nO[CF(CF3)CF2O]mCF(CF3), with n being 0 to 5 and m being 0 to 5;
- and (CF3)2CF(CF2)n, with n being 0 to 10.
A method for recovery of an organic fluoro-compound, which comprises:
- adsorbing the organic fluoro-compound with an adsorbent from an aqueous solution containing the organic fluoro-compound;
- and
- washing the adsorbed organic fluoro-compound with an organic solvent,
- wherein the adsorbent comprises cyclodextrin supported on the surface of a water-insoluble polymer,
- wherein the water-insoluble polymer comprises polystyrene particles,
- wherein the polystyrene particles and the cyclodextrin are chemically bonded via a divalent linking group —X— in which
- X is N, O, S, O(CH2)nO, with n being 1 to 6, or
- X is O(CH2CH2O)n, with n being 2 to 6, and
- the hyphen “-” is a single bond;
- and
- wherein the organic fluoro-compound is selected from the group consisting of fluoroalkane carboxylic acids (R—COOH), fluoroalkane sulfonic acids (R—SO3H), fluoroalkyl alcohols (R—(CH2)nOH, with n being 1 to 6, and a mixture thereof, in which R is selected from the group consisting of CF3(CF2)n, with n being 0 to 11;
- HCF2(CF2)n with n being 0 to 11;
- CF3(CF2)nO[CF(CF3)CF2O]mCF(CF3), with n being 0 to 5 and m being 0 to 5;
- and (CF3)2CF(CF2)n, with n being 0 to 10.
Dependencies are inferred from the claim text.