Efficient dissociation of water vapor in arrays of microchannel plasma devices

Patent metadata

Field	Value
Publication number	US-10240815-B2
Application number	US-201615150107-A
Country	US
Kind code	B2
Filing date	May 9, 2016
Priority date	May 8, 2015
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

The invention provides methods and systems for water dissociation with microplasma generated in microchannel plasma arrays or chips. Preferred methods and systems introduce water vapor into a microchannel plasma array. Electrical power is applied to the microchannel plasma array to create a plasma chemical reaction of the water vapor in the microchannel plasma array. Dissociated hydrogen and/or oxygen gas is collected at an output of the microchannel plasma array. The water vapor can be entrained in a carrier gas, but is preferably introduced without carrier gas. Direct introduction of water vapor has been demonstrated to provide efficiencies at an above 60%. The use of carrier gas reduces efficiency, but still exceeds efficiencies of prior methods discussed in the background.

First claim

The invention claimed is:

1. A method for dissociating water into hydrogen and oxygen, comprising:
introducing water vapor into a microchannel plasma array, wherein the microchannel plasma array comprises a plurality of microchannels isolated from electrodes via dielectric, wherein the microchannels in the array are arranged for a dielectric barrier discharge plasma excitation in the microchannels;
applying electrical power to the microchannel plasma array to create a plasma chemical reaction of the water vapor in the microchannels of the microchannel plasma array and create hydrogen and/or oxygen gas; and
collecting dissociated hydrogen and/or oxygen gas at an output of the microchannel plasma array.

2. The method of claim 1 , wherein said introducing comprises introducing the water vapor entrained in a carrier gas.

3. The method of claim 2 , wherein said introducing creates a flow rate of the water vapor entrained in gas of ˜100 sccm and ˜100 slm at a pressure between 10 Torr and 10 bar, and said applying electrical power comprises applying ˜1-100 W of power per microchannel plasma chip.

4. The method of claim 2 , wherein the carrier gas is one of He, Ne, or Ar.

5. The method of claim 1 , wherein said introducing comprises introducing the water vapor directly into the microchannel plasma array without separately introducing carrier gas to entrain the water vapor.

6. The method of claim 5 , further comprising heating water to produce steam and introducing the steam as the water vapor directly into the microchannel plasma array.

7. The method of claim 6 , further comprising cooling a terminus of the microchannel plasma array to obtain unreacted water vapor and recycling the unreacted water vapor for said heating water to produce steam.

8. The method of claim 5 , wherein said introducing creates a flow rate of the water vapor in one microchannel array of ˜0.2 mL/min to ˜5 L/min at a pressure of ˜11.6 Torr to more than one atmosphere, and said applying electrical power comprises applying ˜1-50 W of power.

9. The method of claim 1 , further comprising a hydrophobic dielectric film coating said plurality of microchannels.

10. The method of claim 1 , wherein said water vapor comprises steam.

11. The method of claim 1 , wherein the microchannel plasma array comprises aluminum electrodes buried in nanoporous aluminum oxide.

Assignees

• Univ Illinois

Inventors

• Dai Zhen
• Houlahan Thomas J
• Eden J Gary
• Park Sung-Jin

Classifications

• B01J2219/0086

  Dimensions of the flow channels · CPC title

• B01J19/0093

  Microreactors, e.g. miniaturised or microfabricated reactors (laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027) · CPC title

• Y02E60/364

  Cross-Sectional Technologies · mapped topic

• C01B2203/0861

  by plasma · CPC title

• B01J2219/00853

  Employing electrode arrangements · CPC title