Ionic liquid and forward osmosis process employing the same

Patent metadata

Field	Value
Publication number	US-11235283-B2
Application number	US-201916729910-A
Country	US
Kind code	B2
Filing date	Dec 30, 2019
Priority date	Dec 30, 2019
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

An ionic liquid and a forward osmosis process employing the same are provided. The ionic liquid has a structure represented by Formula (I)ABn  Formula (I),wherein A isn is 1 or 2; m is 0, or an integer from 1 to 7; R1 and R2 are independently methyl or ethyl; k is an integer from 3 to 8; B isi is independently 1, 2, or 3; and j is 5, 6, or 7. The forward osmosis process employing the ionic liquid is used to desalinate a brine via a forward osmosis (FO) model.

First claim

What is claimed is:

1. An ionic liquid, having a structure represented by Formula (I):
AB n   Formula (I),

wherein A is

n is 1 or 2; m is 0, or an integer from 1 to 7; R 1 and R 2 are independently methyl or ethyl; k is an integer from 3 to 8; B is

i is independently 1, 2, or 3; and j is 5, 6, or 7.

2. The ionic liquid as claimed in claim 1 , wherein n=1; A is

m is 0, 1, or 2; R 1 and R 2 are independently methyl or ethyl; B is

and j is an integer from 5 to 7.

3. The ionic liquid as claimed in claim 2 , wherein A is

n is 1; m is 0; R 1 and R 2 are methyl; B is

and j is 7.

4. The ionic liquid as claimed in claim 1 , wherein n=1; A is

m is 5, 6, or 7; R 1 and R 2 are independently methyl or ethyl; B is

and i is independently 1, 2, or 3.

5. The ionic liquid as claimed in claim 4 , wherein A is

n is 1; m is 7; R 1 and R 2 are ethyl; B is

and i is 3.

6. The ionic liquid as claimed in claim 1 , wherein n=2; A is

k is an integer from 3 to 8; B is

and i is independently 1, 2, or 3.

7. The ionic liquid as claimed in claim 1 , wherein A is

k is 8; n is 2; B is

and i is 3.

8. A forward osmosis process, comprising:
providing a semi-permeable membrane, wherein a draw solution tank is separated from a feed water tank by the semi-permeable membrane;
introducing a draw solution into the draw solution tank, wherein the draw solution comprises the ionic liquid as claimed in claim 1 ;
introducing brine into the feed water tank, wherein an osmotic pressure of the brine is lower than an osmotic pressure of the ionic liquid so that water of the brine permeates through the semi-permeable membrane into the draw solution to obtain a diluted draw solution;
extracting the diluted draw solution from the draw solution tank; and
subjecting the diluted draw solution to a temperature control treatment so that the diluted draw solution is subsequently separated into a water phase and an ionic liquid phase.

9. The forward osmosis process as claimed in claim 8 , wherein the draw solution comprises water and the ionic liquid as claimed in claim 1 .

10. The forward osmosis process as claimed in claim 9 , wherein the amount of ionic liquid is 10 wt % to 70 wt %, based on the weight of the draw solution.

11. The forward osmosis process as claimed in claim 8 , wherein the temperature control treatment is a cooling treatment.

12. The forward osmosis process as claimed in claim 11 , wherein A is

n is 1; m is 0; R 1 and R 2 are methyl; B is

j is 7.

13. The forward osmosis process as claimed in claim 12 , wherein the diluted draw solution exhibits an upper critical solution temperature (UCST) phase separation below 10° C.-35° C.

14. The forward osmosis process as claimed in claim 8 , wherein the temperature control treatment is a heating treatment.

15. The forward osmosis process as claimed in claim 14 , wherein A is

n is 1; m is 7; R 1 and R 2 are ethyl; B is

and i is 3.

16. The forward osmosis process as claimed in claim 15 , wherein the diluted draw solution exhibits a lower critical solution temperature (LCST) phase separation above 43° C.-60° C.

17. The forward osmosis process as claimed in claim 15 , further comprising, after subjecting the diluted draw solution to the temperature control treatment, introducing the ionic liquid phase into the draw solution tank.

18. The forward osmosis process as claimed in claim 14 , wherein A is

k is 8; n is 2; B is

and i is 3.

19. The forward osmosis process as claimed in claim 18 , wherein the diluted draw solution exhibits a lower critical solution temperature (LCST) phase separation above 65° C.-75° C.

Assignees

• Ind Tech Res Inst

Inventors

• Liu Po-I
• Shao Hsin
• Chang Min-Chao
• Chen Yi-Chun
• Huang Chiung-Hui
• Ho Chia-Hua
• Wang David Chiuni
• Horng Ren-Yang

Classifications

• B01D61/005 Primary

  Osmotic agents; Draw solutions · CPC title

• C02F1/68

  by addition of specified substances, e.g. trace elements, for ameliorating potable water (medicinal water A61K) · CPC title

• Y02A20/131

  Reverse-osmosis · CPC title

• C02F2209/02

  Temperature · CPC title

• C07C47/19

  containing hydroxy groups (sugars C07H) · CPC title