Water purification using porous carbon electrode

Patent metadata

Field	Value
Publication number	US-12091343-B2
Application number	US-201815892923-A
Country	US
Kind code	B2
Filing date	Feb 9, 2018
Priority date	Feb 9, 2017
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

A water purification electrode composed of a porous carbon material is disclosed. The electrode may be used as a flow-through cathode in an electro-peroxone process providing high H2O2 production activity for electrochemical wastewater treatment. The porous carbon material is a binding agent-free carbon structure that enables H2O2 to be electro-generated in situ at cathode. The porous carbon material may be synthesized from resorcinol and can provide a relatively large reaction surface area of 200-800 m2/g. The porous carbon material also achieves low energy consumption as well as a wide pH working range, making it suitable for treating many types of organic, inorganic, and biological contaminants in water. The electrode may be integrated with an anode, ozone generator, and other components into a compact, integrated water purification system.

First claim

What is claimed is:

1. A water treatment system using an electro-peroxone process, comprising:
an activated carbon filter receiving influent water;
an electrochemical reactor (ECR) receiving water output from the activated carbon filter, including:
an anode having a plurality of openings configured to allow the water output from the activated carbon filter to flow through the anode;
a flow-through cathode, receiving water output from the anode, the cathode including a porous carbon material configured to admit flowing water to be de-contaminated by an electro-peroxone process performed within the porous carbon material, the porous carbon material including a carbonized, organic-amine-base-catalyzed, porous resorcinol-formaldehyde (RF) polymer, wherein the porous carbon material is synthesized by:
providing a solution consisting of resorcinol and a surfactant in a mixture of ethanol and water;
adding formaldehyde to the solution;
adding an organic-amine base, as a catalyst, to the solution to form a solution mixture;
heating the solution mixture to produce a solidified material;
drying the solidified material; and
performing pyrolysis on the dried solidified material under a protective gas, resulting in the porous carbon material;

the porous carbon material configured to receive oxygen from an oxygen source and configured to receive ozone from an ozone generator;
wherein the cathode is configured to electro-generate H 2 O 2 and perform the electro-peroxone process in situ within the porous carbon material using the received oxygen and the received ozone, the received ozone and the electro-generated H 2 O 2 for purifying the flowing water as the water flows through the porous carbon material;
a non-conductive spacer located between the anode and the cathode to prevent electrical contact between the anode and the cathode; and
an electrical conductor contacting the porous carbon material, the electrical conductor having a plurality of openings configured to allow the water to flow through the cathode; and

the ozone generator configured to introduce ozone into water flowing into the ECR.

2. The system of claim 1 , wherein the system is portable.

3. The system of claim 2 , further comprising a voltage source connected to the anode and the cathode.

4. The system of claim 3 , further comprising a polishing filter, receiving water output from the ECR, configured to remove contaminants from the water flow by size exclusion.

5. The system of claim 4 , further comprising a water pump for moving water through the activated carbon filter, the ECR and the polishing filter.

6. The system of claim 5 , further comprising a housing configured for continuous flow of the water therethrough and configured to contain the activated carbon filter, the ECR, the voltage source, the polishing filter, the water pump, and the ozone generator.

7. The system of claim 6 , further comprising a control unit located in the housing, the control unit for adjusting ozone generation of the ozone generator, water flow rate of the water pump, and voltage applied by the voltage source to the anode and the cathode.

8. The system of claim 7 , further comprising:
an air pump, contained in the housing and operatively coupled to the ozone generator, for supplying air to the ozone generator.

9. A flow-through electrode for water purification using an electro-peroxone process, comprising:
a porous carbon material configured to admit flowing water to be de-contaminated within the porous carbon material, the porous carbon material comprising a carbonized, organic-amine-base-catalyzed, porous resorcinol-formaldehyde (RF) polymer, wherein the porous carbon material is synthesized by:
providing a solution consisting of resorcinol and a surfactant in a mixture of ethanol and water;
adding formaldehyde to the solution;
adding an organic-amine base, as a catalyst, to the solution to form a solution mixture;
heating the solution mixture to produce a solidified material;
drying the solidified material; and
performing pyrolysis on the dried solidified material under a protective gas, resulting in the porous carbon material;
the porous carbon material configured to receive oxygen from an oxygen source and configured to receive ozone from an ozone generator;
wherein the electrode is configured to electro-generate H 2 O 2 and perform the electro-peroxone process in situ within the porous carbon material using the received oxygen and the received ozone, the received ozone and the electro-generated H 2 O 2 for purifying the flowing water as the water flows through the porous carbon material.

10. The electrode of claim 9 , wherein the organic-amine-base catalyst is selected from the group consisting of 1,6-diaminohexane, ethylenediamine (EDA), trimethylamine (TMA), and triethylamine (TEA).

11. The electrode of claim 9 , wherein the surfactant is poloxamer 407.

12. The electrode of claim 9 , wherein the protective gas is selected from the group consisting of nitrogen, hydrogen and an inert gas.

13. The electrode of claim 9 , wherein a porosity of the porous carbon material is tuned by adjusting a polymerization process used to form the porous carbon material.

14. The electrode of claim 9 , wherein the porous carbon material is formed into a predetermined three-dimensional object.

15. The electrode of claim 9 , wherein the porous carbon material has a structure that provides a reaction surface area of 200-800 m 2 /g.

16. The electrode of claim 9 , further comprising a metallic conductor in electrical contact with the porous carbon material.

17. The electrode of claim 9 , wherein the porous carbon material lacks a binding agent.

Assignees

• California Inst Of Techn

Inventors

• Liu Kai
• Hoffmann Michael R

Classifications

• C02F1/4691

  Capacitive deionisation · CPC title

• Y02W10/37

  using solar energy · CPC title

• C02F2201/46165

  Special power supply, e.g. solar energy or batteries · CPC title

• C02F2209/006

  comprising a software program or a logic diagram · CPC title

• C02F2201/46125

  Electrical variables · CPC title