Methods for co-producing hydrocarbon products and ammonia
A method of a hydrocarbon product and ammonia comprises introducing C 2 H 6 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. N 2 is introduced to the negative electrode of the electrochemical cell. A potential difference is applied between the positive electrode and the negative electrode of the electrochemical cell. A system for co-producing higher hydrocarbons and NH 3 , and an electrochemical cell are also described.
1. A method of forming a hydrocarbon product and ammonia, comprising:
introducing ethane (C 2 H 6 ) to a positive electrode of an electrochemical cell comprising:
the positive electrode;
a negative electrode comprising one or more of a Ru/perovskite cermet, a RuNi/perovskite cermet, a RuCe/perovskite cermet, and a RuNiCe/perovskite cermet; 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.;
introducing N 2 to the negative electrode of the electrochemical cell; and
applying a potential difference between the positive electrode and the negative electrode of the electrochemical cell while the C 2 H 6 interacts with the positive electrode so that hydrogen (H) atoms of the C 2 H 6 release electrons (e − ) to produce C 2 H 4 , hydrogen ions (H + ), and the e − at the positive electrode through non-oxidative deprotonation of the C 2 H 6 at the one or more temperatures, to transport the H + through the proton-conducting membrane, and to produce NH 3 at the negative electrode.
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 a yttrium- and ytterbium-doped barium-zirconate-cerate (BZCYYb), a yttrium- and ytterbium-doped barium-strontium-niobate (BSNYYb), yttrium-doped BaCeO 3 , yttrium-doped BaZrO 3 , Ba 2 (YSn)O 5.5 , and Ba 3 (CaNb 2 )O 9 .
4. The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise one or more of a yttrium- and ytterbium-doped barium-zirconate-cerate (BZCYYb), and a yttrium- and ytterbium-doped barium-strontium-niobate (BSNYYb).
5. The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise a yttrium- and ytterbium-doped barium-zirconate-cerate (BZCYYb).
6. The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise a yttrium- and ytterbium-doped barium-strontium-niobate (BSNYYb).
7. The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise Ba 2 (YSn)O 5.5 .
8. The method of claim 1 , further comprising selecting the proton-conducting membrane to comprise Ba 3 (CaNb 2 )O 9 .
9. The method of claim 1 , further comprising selecting the negative electrode to comprise the Ru/perovskite cermet, the Ru/perovskite cermet selected from a Ru/yttrium- and ytterbium-doped barium-zirconate-cerate (Ru-BZCYYb) cermet and a Ru/yttrium- and ytterbium-doped barium-strontium-niobate (Ru-BSNYYb) cermet.
10. The method of claim 1 , further comprising selecting the negative electrode to comprise the RuNi/perovskite cermet, the RuNi/perovskite cermet selected from a RuNi/yttrium- and ytterbium-doped barium-zirconate-cerate (RuNi-BZCYYb) cermet and a RuNi/yttrium- and ytterbium-doped barium-strontium-niobate (RuNi-BSNYYb) cermet.
11. The method of claim 10 , wherein catalyst material of the RuNi/perovskite cermet comprises one or more of:
RuNi alloy particles; and
composite particles individually comprising:
a core comprising one of Ru, Ni, and an RuNi alloy; and
a shell partially coating the core and having a different material composition than the core, the shell comprising one other of the Ru, the Ni, and the RuNi alloy.
12. The method of claim 1 , further comprising selecting the negative electrode to comprise the RuCe/perovskite cermet, the RuCe/perovskite cermet selected from a RuCe/yttrium- and ytterbium-doped barium-zirconate-cerate (RuCe-BZCYYb) cermet and a RuCe/yttrium- and ytterbium-doped barium-strontium-niobate (RuCe-BSNYYb) cermet.
13. The method of claim 12 , wherein catalyst material of the RuCe/perovskite cermet comprises one or more of:
RuCe alloy particles; and
composite particles individually comprising:
a core comprising one of Ru, Ce, and a RuCe alloy; and
a shell partially coating the core and having a different material composition than the core, the shell comprising one other of the Ru, the Ce, and the RuCe alloy.
14. The method of claim 1 , further comprising selecting the negative electrode to comprise the RuNiCe/perovskite cermet, the RuNiCe/perovskite cermet selected from a RuNiCe/yttrium- and ytterbium-doped barium-zirconate-cerate (RuNiCe-BZCYYb) cermet and a RuNiCe/yttrium- and ytterbium-doped barium-strontium-niobate (RuNiCe-BSNYYb) cermet.
15. The method of claim 14 , wherein catalyst material of the RuNiCe/perovskite cermet comprises one or more of:
RuNiCe alloy particles; and
composite particles individually comprising Ru, Ni, and Ce.