Draw solutions and related methods for treating a liquid

Patent metadata

Field	Value
Publication number	US-2016016115-A1
Application number	US-201414333362-A
Country	US
Kind code	A1
Filing date	Jul 16, 2014
Priority date	Jul 16, 2014
Publication date	Jan 21, 2016
Grant date	—

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 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; and
a secondary solvent.

2 . The draw solution of claim 1 , wherein n is 1 and n′ is 1.

3 . The draw solution of claim 1 , 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 hydrogen group.

4 . The draw solution of claim 1 , wherein the at least one N-cyclicalkyl-cycloalkylamine comprises 1-cyclohexylpiperidine.

5 . The draw solution of claim 1 , wherein the secondary solvent comprises water, an alcohol, or combinations thereof.

6 . The draw solution of claim 1 , wherein a nonpolar faun of the at least one N-cyclicalkyl-cycloalkylamine is immiscible with the secondary solvent.

7 . The draw solution of claim 1 , wherein a polar form of the at least one N-cyclicalkyl-cycloalkylamine is miscible with the secondary solvent.

8 . The draw solution of claim 7 , wherein the polar form of the at least one N-cyclicalkyl-cycloalkylamine comprises an aminium salt of the at least one N-cyclicalkyl-cycloalkylamine.

9 . The draw solution of claim 7 , wherein the polar form of the at least one N-cyclicalkyl-cycloalkylamine comprises a bicarbonate of the at least one N-cyclicalkyl-cycloalkylamine.

10 . 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.

11 . The method of claim 10 , 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.

12 . The method of claim 10 , 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.

13 . The method of claim 10 , 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.

14 . The method of claim 10 , 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.

15 . The method of claim 10 , 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.

16 . The method of claim 10 , 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.

17 . The method of claim 11 , 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.

18 . The method of claim 17 , further comprising separating the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form and the at least one solvent.

19 . The method of claim 18 , further comprising recovering the at least one N-cyclicalkyl-cycloalkylamine in the nonpolar form.

Assignees

• Battelle Energy Alliance Llc

Inventors

• Wilson Aaron D
• Orme Christopher J

Classifications

• B01D2311/06

  Specific process operations in the permeate stream · CPC title

• B01D2311/2653

  Degassing · CPC title

• B01D2311/2661

  Addition of gas · CPC title

• C02F1/445

  by forward osmosis · CPC title

• B01D61/005 Primary

  Osmotic agents; Draw solutions · CPC title