Methods for treating a liquid using draw solutions

Patent metadata

Field	Value
Publication number	US-9399194-B2
Application number	US-201414333362-A
Country	US
Kind code	B2
Filing date	Jul 16, 2014
Priority date	Jul 16, 2014
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

Draw solutions comprising at least one N-cyclicalkyl-cycloalkylamine and a secondary solvent. The N-cyclicalkyl-cycloalkylamine comprises the chemical structure:

wherein n is 0, 1, or 2, n′ is 0, 1, or 2, and each of R 1 -R 6 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydrogen group, a hydroxyl group, and a phosphorus-containing group. Methods of treating a liquid using the draw solution are also disclosed.

First claim

What is claimed is:

1. A method of treating a liquid, the method comprising:
converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form;
contacting one side of a membrane with the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the polar form and an opposite side of the membrane with a feed liquid comprising at least one solvent and at least one solute; and
osmosing the at least one solvent of the feed liquid across the membrane and into the draw solution to form a diluted draw solution and a concentrated feed liquid.

2. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises contacting the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form with a switching agent.

3. The method of claim 2 , further comprising removing the switching agent from the diluted draw solution to form a multiple-phase solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form and the at least one solvent.

4. The method of claim 3 , further comprising separating the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form and the at least one solvent.

5. The method of claim 4 , further comprising recovering the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form.

6. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form to an aminium salt of the at least one N-cyclicalkyl-cycloalkylamine.

7. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form to an aminium carbonate of the at least one N-cyclicalkyl-cycloalkylamine.

8. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises exposing the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form to carbon dioxide.

9. The method of claim 1 , wherein osmosing the at least one solvent of the feed liquid across the membrane and into the draw solution to form a diluted draw solution and a concentrated feed liquid comprises osmosing the at least one solvent of the feed liquid across the membrane and into the draw solution to form a diluted draw solution on the one side of the membrane and a concentrated feed liquid on the opposite side of the membrane.

10. The method of claim 1 , wherein osmosing the at least one solvent of the feed liquid across the membrane and into the draw solution to form a diluted draw solution and a concentrated feed liquid comprises forming the concentrated feed liquid comprising the at least one solute and the diluted draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the polar form.

11. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine comprising the chemical structure:

wherein n is 0, 1, or 2, n′ is 0, 1, or 2, and each of R 1 -R 6 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydrogen group, a hydroxyl group, and a phosphorus-containing group.

12. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine into a draw solution comprising a bicarbonate form of the at least one N-cyclicalkyl-cycloalkylamine.

13. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine into a draw solution comprising the chemical structure:

wherein n is 0, 1, or 2, n′ is 0, 1, or 2, each of R 1 -R 6 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydrogen group, a hydroxyl group, and a phosphorus-containing group, and X is an anionic counterion.

14. The method of claim 1 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine in a nonpolar form into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form comprises converting a draw solution comprising 1 -cyclohexylpiperidine into a draw solution comprising a bicarbonate form of 1 -cyclohexylpiperidine.

15. A method of treating a liquid, the method comprising:
converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine having the chemical structure:

wherein n is 0, 1, or 2, n′ is 0, 1, or 2, and each of R 1 -R 6 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydrogen group, a hydroxyl group, and a phosphorus-containing group, into a draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in a polar form;
contacting one side of a membrane with the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine in the polar form and an opposite side of the membrane with a feed liquid comprising at least one solvent and at least one solute; and
osmosing the at least one solvent of the feed liquid across the membrane and into the draw solution to form a diluted draw solution and a concentrated feed liquid.

16. The method of claim 15 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine comprises converting the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine where is 1 and n′ is 1.

17. The method of claim 15 , wherein converting a draw solution comprising at least one N-cyclicalkyl-cycloalkylamine comprises converting the draw solution comprising the at least one N-cyclicalkyl-cycloalkylamine wherein each of R 1 and R 2 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydroxyl group, and a phosphorus-containing group and each of R 3 -R 6 is a

Assignees

• Battelle Energy Alliance Llc

Inventors

• Wilson Aaron D
• Orme Christopher J

Classifications

• C02F1/445

  by forward osmosis · CPC title

• B01D2311/2661

  Addition of gas · CPC title

• B01D61/005 Primary

  Osmotic agents; Draw solutions · CPC title

• B01D2311/06

  Specific process operations in the permeate stream · CPC title

• B01D2311/2653

  Degassing · CPC title