Methods for producing hydrocarbon products and hydrogen gas through electrochemical activation of methane, and related systems and electrochemical cells

Patent metadata

Field	Value
Publication number	US-2019177861-A1
Application number	US-201816196283-A
Country	US
Kind code	A1
Filing date	Nov 20, 2018
Priority date	Dec 11, 2017
Publication date	Jun 13, 2019
Grant date	—

Abstract

A method of forming a hydrocarbon product and hydrogen gas comprises introducing CH 4 to a positive electrode of an electrochemical cell comprising the positive electrode, a negative electrode, and a proton-conducting membrane between the positive electrode and the negative electrode. The proton-conducting membrane comprises an electrolyte material having an ionic conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 150° C. to about 600° C. A potential difference is applied between the positive electrode and the negative electrode of the electrochemical cell to produce the hydrocarbon product and the hydrogen gas. A CH 4 activation system and an electrochemical cell are also described.

First claim

What is claimed is:

1 . A method of forming a hydrocarbon product and hydrogen gas, comprising:
introducing CH 4 to a positive electrode of an electrochemical cell comprising the positive electrode, a negative electrode, and a proton-conducting membrane between the positive electrode and the negative electrode, the proton-conducting membrane comprising an electrolyte material having an ionic conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 150° C. to about 600° C.; and applying a potential difference between the positive electrode and the negative electrode of the electrochemical cell.

2 . The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise at least one perovskite material having a H + conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 400° C. to about 600° C.

3 . The method of claim 2 , wherein selecting the proton-conducting membrane to comprise at least one perovskite material comprises selecting the at least one perovskite material to comprise one or more of BZCYYb, BSNYYb, BCY, BZY, Ba 2 (YSn)O 5.5 , and Ba 3 (CaNb 2 )O 9 .

4 . The method of claim 2 , further comprising selecting the positive electrode to comprise a catalyst material formulated to accelerate reaction rates to produce CH 3 + , H + , and e − , from CH 4 and to accelerate reaction rates to synthesize higher hydrocarbons from the produced CH 3 + , the catalyst material comprising one or more of Ru, Rh, Ni, Ir, Mo, Zn, Co and Fe.

5 . The method of claim 4 , further comprising selecting the negative electrode to comprise another catalyst material formulated to accelerate reaction rates to produce H 2(g) from H + and e − , the another catalyst material comprising a Ni/perovskite cermet.

6 . The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise at least one solid acid material having a H + conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 200° C. to about 400° C.

7 . The method of claim 6 , wherein selecting the proton-conducting membrane to comprise at least one solid acid material comprises selecting the at least one solid acid material to comprise CsH 2 PO 4 .

8 . The method of claim 7 , further comprising selecting the positive electrode to comprise a catalyst material formulated to accelerate reaction rates to produce CH 3 + , H + , and e − , from CH 4 and to accelerate reaction rates to synthesize higher hydrocarbons from the produced CH 3 + , the catalyst material comprising one or more of Ni and a metallic material comprising Ru and Co.

9 . The method of claim 8 , further comprising selecting the negative electrode to comprise another catalyst material formulated to accelerate reaction rates to produce H 2(g) from H + and e − , the another catalyst material comprising a Pt—CsH 2 PO 4 cermet.

10 . The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise at least one PBI material having a H + conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 150° C. to about 200° C.

11 . The method of claim 10 , wherein selecting the proton-conducting membrane to comprise at least one PBI material comprises selecting the at least one PBI material to comprise H 3 PO 4 -doped PBI.

12 . The method of claim 11 , further comprising selecting the positive electrode to comprise a catalyst material formulated to accelerate reaction rates to produce CH 3 + , H + , and e − , from CH 4 and to accelerate reaction rates to synthesize higher hydrocarbons from the produced CH 3 + , the catalyst material comprising Pd and one or more of Pt and Co.

13 . The method of claim 12 , further comprising selecting the negative electrode to comprise another catalyst material formulated to accelerate reaction rates to produce H 2(g) from H + and e − , the another catalyst material comprising one or more of Ni and Pt.

14 . A CH 4 activation system, comprising:
a source of CH 4 ; and an electrochemical apparatus in fluid communication with the source of CH 4 , and comprising:
a housing structure configured and positioned to receive a CH 4 stream from the source of CH 4 ; and
an electrochemical cell within an internal chamber of the housing structure, and comprising:
a positive electrode comprising a catalyst material formulated to accelerate reaction rates to produce CH 3 + , H + , and e − from CH 4 , and to accelerate reaction rates to synthesize at least one hydrocarbon product from the produced CH 3 + ;
a negative electrode comprising another catalyst material formulated to accelerate reaction rates to produce H 2(g) from H + and e − ; and
a proton-conducting membrane between the positive electrode and the negative electrode and comprising an electrolyte material having an ionic conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 150° C. to about 600° C.

15 . The CH 4 activation system of claim 14 , wherein the electrolyte material of the proton-conducting membrane is selected from the group consisting of:
a perovskite material having a H + conductivity greater than about 10 −2 S/cm at one or more temperatures within a range of from about 400° C. to about 600° C.; a solid acid material having a H + conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 200° C. to about 400° C.; and a PBI material having a H + conductivity greater than or equal to about 10 −2 S/cm at one or more temperatures within a range of from about 150° C. to about 200° C.

16 . The CH 4 activation system of claim 15 , wherein:
the proton-conducting membrane comprises BZCYYb; the catalyst material of the positive electrode comprises one or more of Fe@SiO 2 and Mo 2 C; and the another catalyst material of the negative electrode comprises Ni—BZCYYb.

17 . The CH 4 activation system of claim 15 , wherein:
the proton-conducting membrane comprises CsH 2 PO 4 ; the catalyst material of the positive electrode comprises one or more of Ni and a Ru—Co bimetallic compound; and the another catalyst material of the negative electrode comprises Pt—CsH 2 PO 4 .

18 . The CH 4 activation system of claim 15 , wherein:
the proton-conducting membrane comprises H 3 PO 4 -doped PBI; the catalyst material of the positive electrode comprises one or more of a Pd—Co bimetallic compound, a Pd—Pt bimetallic compound, and a Pd—Pt—Co trimetallic compound; and the another catalyst material of the negative electrode comprises one or more of Ni and P.

19 . The CH 4 activation system of claim 14 , further comprising a heating apparatus configured and positioned to heat one or more of the CH 4 stream and at least a portion of the electrochemical apparatus.

20 . An electrochemical cell, comprising:
a positive electrode comprising a first catalyst material formulated to accelerate to CH 4 deprotonation reaction rates to produce CH 3 + , H + , and e − , from CH 4 , and to accelerate coupling reaction rates to synthesize at least one hydrocarbon product from the produced CH 3 + ; a negative electrode comprising a second catalyst material formulated to accelerate hydrogen evolution reaction rates to produce H 2(g) from H + and e − ; and a proton-conducting

Assignees

• Battelle Energy Alliance Llc

Inventors

• Ding Dong
• He Ting
• Wu Wei
• Zhang Yunya

Classifications

• C25B3/00 Primary

  Electrolytic production of organic compounds · CPC title

• C25B11/0473

  Chemistry & Metallurgy · mapped topic

• C25B11/0452

  Chemistry & Metallurgy · mapped topic

• C25B1/02

  Hydrogen or oxygen · CPC title

• C25B9/08

  Chemistry & Metallurgy · mapped topic