Hydrogen gas production device and hydrogen gas production method

Patent metadata

Field	Value
Publication number	US-10882005-B2
Application number	US-201615748069-A
Country	US
Kind code	B2
Filing date	Jul 25, 2016
Priority date	Jul 28, 2015
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

A hydrogen gas producing apparatus includes a porous body (100) and a mixed gas source (300). The porous body (100) is permeable to hydrogen gas and carbon dioxide gas, and has a property of being more permeable to hydrogen gas than carbon dioxide gas. The mixed gas source (300) causes a mixed gas including carbon dioxide gas and hydrogen gas to flow into the porous body (100) under a condition that a pressure gradient represented by (P1−P2)/L is below 50 MPa/m, where L represents the length of the porous body (100) in a direction in which the mixed gas permeates; P1 represents an inflow pressure of the mixed gas into the porous body (100); and P2 represents an outflow pressure thereof from the porous body (100).

First claim

The invention claimed is:

1. A hydrogen gas producing apparatus, comprising:
a porous body that (i) is formed of a ceramic and (ii) has a cumulative pore diameter distribution in which a pore diameter (D80) at a number cumulative frequency of 80% is 800 nm or less, thereby causing the porous body to be permeable to hydrogen gas and to carbon dioxide gas and to have a property of being more permeable to the hydrogen gas than to the carbon dioxide gas;
a gas flow channel that includes a flow inlet at one end thereof and a flow outlet at another end thereof, the porous body being disposed inside the gas flow channel; and
a mixed gas source that causes a mixed gas to flow into the porous body through the flow inlet the mixed gas including the carbon dioxide gas and the hydrogen gas and having a carbon dioxide gas concentration of 50% by mole or less,
wherein
a pressure gradient represented by (P 1 − P 2 )/L is 10 M Pa/m or less where L represents a length of the porous body in a direction in which the mixed gas permeates, P 1 represents an inflow pressure of the mixed gas into the porous body, and P 2 represents an outflow pressure from the porous body,
the mixed gas is caused to flow into the porous body under a temperature environment at room temperature.

2. A hydrogen gas producing apparatus, comprising:
a porous body that (i) is formed of a ceramic and (ii) has a cumulative pore diameter distribution in which a pore diameter (D80) at a number cumulative frequency of 80% is 800 nm or less, thereby causing the porous body to be permeable to hydrogen gas and to carbon dioxide gas and to have a property of being more permeable to the hydrogen gas than to the carbon dioxide gas;
a gas flow channel that includes a flow inlet at one end thereof and a flow outlet at another end thereof, the porous body being disposed inside the gas flow channel; and
a mixed gas source that causes a mixed gas to flow into the porous body through the flow inlet, the mixed gas including the carbon dioxide gas and the hydrogen gas; and
a heater to heat at least one of the porous body or the mixed gas,
wherein
a pressure gradient represented by (P 1 − P 2 )/L is less than 50 M Pa/m where L represents a length of the porous body in a direction in which the mixed gas permeates, P 1 represents an inflow pressure of the mixed gas into the porous body, and P 2 represents an outflow pressure from the porous body,
the mixed gas is flowed into the porous body under a temperature environment heated to 200° C. or higher by the heater.

3. The hydrogen gas producing apparatus according to claim 2 , wherein the mixed gas source causes the mixed gas to flow into the porous body under a condition that the pressure gradient is 7.5 MPa/m or less or 10 MPa/m or more.

4. The hydrogen gas producing apparatus according to claim 1 or 2 , wherein the ceramic comprises one or more inorganic materials selected from an alumina material, an yttria-stabilized zirconia material, and a silicon carbide material.

5. A hydrogen gas producing method comprising:
preparing a mixed gas that includes carbon dioxide gas and hydrogen gas and has a carbon dioxide gas concentration of 50% by mole or less; and
causing, under a temperature environment at room temperature, the mixed gas to flow into a porous body that (i) is formed of a ceramic and (ii) is permeable to the hydrogen gas and to the carbon dioxide gas
wherein
the porous body has a cumulative pore diameter distribution in which a pore diameter (D80) at a number cumulative frequency of 80% is 800 nm or less, thereby causing the porous body to have a property of being more permeable to the hydrogen gas than to the carbon dioxide gas,
a pressure gradient represented by (P 1 − P 2 )/L is 10 MPa/m or less where L represents a length of the porous body in a direction in which the mixed gas permeates, P 1 represents an inflow pressure of the mixed gas into the porous body, and P 2 represents an outflow pressure from the porous body.

6. A hydrogen gas producing method comprising:
preparing a mixed gas including carbon dioxide gas and hydrogen gas; and
causing, under a temperature environment at 200° C. or higher, the mixed gas to flow into a porous body that (i) is formed of a ceramic and (ii) is permeable to the hydrogen gas and to the carbon dioxide gas,
wherein
the porous body has a cumulative pore diameter distribution in which a pore diameter (D80) at a number cumulative frequency of 80% is 800 nm or less, thereby causing the porous body to have a property of being more permeable to the hydrogen gas than to the carbon dioxide gas,
a pressure gradient represented by (P 1 − P 2 )/L is less than 50 MPa/m where L represents a length of the porous body in a direction in which the mixed gas permeates, P 1 represents an inflow pressure of the mixed gas into the porous body, and P 2 represents an outflow pressure from the porous body.

Assignees

• Univ Kagoshima

Inventors

• Hirata Yoshihiro
• Shimonosono Taro
• IMADA Hikari

Classifications

• B01D2325/0283

  Pore size · CPC title

• B01D67/00411

  by sintering · CPC title

• B01D71/022

  Metals · CPC title

• B01D69/02

  characterised by their properties · CPC title

• C04B2235/5445

  submicron sized, i.e. from 0,1 to 1 micron · CPC title