Electrochemical carbon nanotube filter and method

Patent metadata

Field	Value
Publication number	US-9827517-B2
Application number	US-201213439073-A
Country	US
Kind code	B2
Filing date	Apr 4, 2012
Priority date	Jan 25, 2011
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A filtration apparatus and filtration method can be used to reduce at least one contaminant (e.g., organic molecules, ions and/or biological microorganisms) in an aqueous fluid. The filtration apparatuses and methods of the invention can separate at least one contaminant from an aqueous fluid and/or oxidize at least one contaminant. In operation, an aqueous fluid is flowed through a filtration apparatus comprising a porous carbon nanotube filter material at an applied voltage. In some embodiments, the filtration apparatus described herein can be used for dead-end filtration. In some embodiments, the filtration apparatus described herein can be used for cross-over filtration.

First claim

What is claimed:

1. A filtration apparatus, comprising:
a housing forming a chamber having a plane, the chamber including an inlet for receiving an input fluid, a first outlet for releasing fluid, and a second outlet for releasing filtered fluid, wherein the inlet and the first outlet are disposed on a first side of the plane, and the second outlet is disposed on a second side of the plane;
a filter positioned along the plane between the inlet and the second outlet, the filter comprising at least one porous polymer layer disposed between a first porous carbon nanotube filter material and a second porous carbon nanotube filter material;
a first conducting connector positioned along the plane between the inlet and the carbon nanotube-based filter; and
a second conducting connector positioned along the plane between the carbon nanotube-based filter and the second outlet;
wherein the first and the second porous carbon nanotube filter material have an average pore size of at least about 0.5 nm; and
wherein the first and the second porous carbon nanotube filter material have a specific surface area of about 80 m 2 /g to about 120 m 2 /g.

2. The apparatus of claim 1 , wherein the first conducting connector is in contact with a portion of the first porous carbon nanotube filter material.

3. The apparatus of claim 1 , wherein the second conducting connector is in contact with a portion of the second porous carbon nanotube filter material.

4. The apparatus of claim 1 , wherein at least one of the first conducting connector and the second conducting connector has a thickness of about 100 μm to about 150 μm.

5. The apparatus of claim 1 , wherein the first conducting connector and the second conducting connector are electrically separated from each other to prevent a short circuit.

6. The apparatus of claim 5 , wherein the first conducting connector and the second conducting connector each comprises at least one hole designed for a peg to align the first conducting connector and the second conducting connector with the filter.

7. The apparatus of claim 6 , wherein a rim of the hole is coated with an electrically insulating layer.

8. The apparatus of claim 6 , wherein the peg is an electrically-insulating peg.

9. The apparatus of claim 1 , wherein at least one of the first conducting connector and the second conducting connector includes titanium.

10. The apparatus of claim 1 , wherein a flux through the porous polymer layer is at least 70% of a flux through the first porous carbon nanotube filter material or the second porous carbon nanotube filter material.

11. The apparatus of claim 10 , wherein the porous polymer layer has a pore size of about 0.01 μm to about 5 μm.

12. The filtration apparatus of claim 1 , wherein the first and the second porous carbon nanotube filter materials comprise undoped carbon nanotubes, nitrogen-doped carbon nanotubes, boron-doped carbon nanotubes, fluorine-doped carbon nanotubes or any combinations thereof.

13. The filtration apparatus of claim 12 , wherein the carbon nanotubes are multi-walled carbon nanotubes.

14. The filtration apparatus of claim 1 , wherein the first conducting connector and the second conducting connector are connected to an electrical power source and produce an electric potential of 3 volts or less between the first porous carbon nanotube filter material and the first porous carbon nanotube filter material.

Assignees

• Vecitis Chad D
• Van Fossen Kirsten
• Harvard College

Inventors

• Vecitis Chad D
• Van Fossen Kirsten

Classifications

• B01D2239/065

  More than one layer present in the filtering material · CPC title

• B01D35/06 Primary

  Filters making use of electricity or magnetism (ultrafiltration, microfiltration B01D61/14; electrodialysis, electro-osmosis B01D61/42; devices comprising filters and magnetic separators B03C1/30) · CPC title

• B01D39/2055 Primary

  Carbonaceous material (solid sorbent compositions comprising free carbon B01J20/20) · CPC title

• B82Y30/00

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

• C02F1/4672

  by electrooxydation · CPC title