CNT-based reverse osmosis desalination

Patent metadata

Field	Value
Publication number	US-11364472-B1
Application number	US-202016881220-A
Country	US
Kind code	B1
Filing date	May 22, 2020
Priority date	May 22, 2020
Publication date	Jun 21, 2022
Grant date	Jun 21, 2022

Abstract

The present disclosure relates to nanochannel plates for use in reverse osmosis systems and methods of their manufacture. An example nanochannel plate includes a first surface and an opposing second surface. The first surface and the second surface are parallel to a major flat of the nanochannel plate. The nanochannel plate also includes a plurality of channels. At least one channel includes a carbon nanotube having a first end opening proximate to the first surface and a second end opening proximate to the second surface. Optionally, a core portion of the carbon nanotube could be configured to transport water from the first surface to the second surface or vice versa. Optionally, the core portion of the carbon nanotube has a core diameter of less than or equal to 0.7 nanometers.

First claim

What is claimed is:

1. A method comprising:
inserting a plurality of carbon nanotubes into a core portion of a tube preform, wherein the core portion is disposed along a long axis of the tube preform;
heating at least a portion of the tube preform;
pulling the tube preform along the long axis so as to lengthen and narrow the tube preform and thereby providing a pulled preform;
cutting the pulled preform into portions; and
bundling the pulled preform portions.

2. The method of claim 1 , further comprising:
fusing the bundled pulled preform portions to provide a fused bundle; and
cutting the fused bundle along a plane transverse to the long axis to form at least one nanochannel plate.

3. The method of claim 2 , further comprising:
applying a coating to at least a portion of the at least one nanochannel plate, wherein the coating comprises a hydrophobic material.

4. The method of claim 3 , wherein the hydrophobic material comprises fluorinated silane.

5. The method of claim 2 , wherein the at least one nanochannel plate has a first surface and an opposing second surface, wherein the first surface and the second surface are parallel to a major flat of the at least one nanochannel plate.

6. The method of claim 5 , wherein the at least one nanochannel plate comprises a plurality of channels, wherein at least one channel comprises a carbon nanotube having a first end opening proximate to the first surface and a second end opening proximate to the second surface.

7. The method of claim 6 , wherein a core portion of the carbon nanotube is configured to transport water from the first surface to the second surface or vice versa.

8. The method of claim 6 , wherein a core portion of the carbon nanotube has a core diameter of less than or equal to 0.7 nanometers.

9. The method of claim 1 , wherein the tube preform comprises a glass material.

10. The method of claim 9 , wherein the glass material comprises at least one of: a borosilicate glass, soda lime glass, or quartz glass.

11. The method of claim 1 , wherein the tube preform comprises a polymer.

12. The method of claim 1 , wherein the tube preform comprises a metal.

13. The method of claim 1 , further comprising:
forming a carbon nanotube solution, wherein the carbon nanotube solution comprises carbon nanotubes suspended in a liquid; and
heating the carbon nanotube solution so as to evaporate the liquid and to provide a carbon nanotube powder, wherein inserting the plurality of carbon nanotubes into the core portion of the tube preform comprises inserting the carbon nanotube powder into the core portion of the tube preform.

14. The method of claim 13 , wherein the liquid comprises at least one of: water or sodium silicate.

15. The method of claim 1 , further comprising:
repeating at least the heating, pulling, cutting, and bundling steps a predetermined number of times.

16. The method of claim 1 , wherein cutting the pulled preform into portions is performed by a laser cutting tool.

17. The method of claim 1 , wherein cutting the pulled preform into portions comprises cutting the pulled preform into portions having substantially equal lengths.

18. The method of claim 1 , wherein pulling the tube preform is carried out using a drawing tower system.

Assignees

• Waymo Llc

Inventors

• Simpson John

Classifications

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• B01D2323/04

  Hydrophobization · CPC title

• B01D67/0055

  by mechanical treatment · CPC title

• B01D67/0041

  by agglomeration of particles in the dry state · CPC title

• B01D61/025

  Reverse osmosis; Hyperfiltration · CPC title