Non-Faradaic electrochemical promotion of catalytic methane reforming for methanol production
A method of converting methane to methanol at low temperatures utilizes a reactor including an anode, a cathode, a membrane separator between the anode and cathode, a metal oxide catalyst at the anode and a hydrogen recovery catalyst at the cathode. The method can convert methane to methanol at as rate exceeding the theoretical Faradaic rate due to the contribution of an electrochemical reaction occurring in tandem with a Faradaic reaction.
1. A method of converting methane to methanol, comprising the steps of:
providing a reactor including an anode, a cathode, and a membrane separator between the anode and the cathode;
feeding methane to the anode, and electrochemically converting the methane to methanol and electrons in the presence of a metal oxide catalyst at the anode;
feeding an aqueous alkaline solution to the cathode;
conducting the electrons to the cathode, thereby transforming water at the cathode to hydrogen gas and hydroxide ions;
transforming the hydroxide ions through the membrane separator to the anode, causing regeneration of the metal oxide catalyst; and
recovering the methanol from the reactor.
2. The method of claim 1 , wherein the membrane separator includes an anode side and a cathode side, further comprising the steps of providing the metal oxide catalyst on the anode side and providing a hydrogen evolution catalyst on the cathode side.
3. The method of claim 2 , wherein the hydrogen evolution catalyst comprises a metal selected from platinum, iron, ruthenium, osmium, and combinations thereof.
4. The method of claim 1 , wherein the membrane separator comprises a porous layer containing an alkaline polymer electrolyte.
5. The method of claim 1 , wherein the membrane separator comprises a porous layer containing an acidic polymer electrolyte.
6. The method of claim 1 , wherein the membrane separator comprises a porous layer containing both an alkaline polymer electrolyte and an acidic polymer electrolyte.
7. The method of claim 1 , wherein the metal oxide catalyst comprises a metal selected from the group consisting of nickel, cobalt, copper, silver, platinum gold, cerium, lead, iron, manganese, zinc, and combinations thereof.
8. The method of claim 1 , wherein the metal oxide catalyst is selected from the group consisting of nickel hydroxide, iron hydroxide, zinc hydroxide, manganese hydroxide, cobalt hydroxide, and combinations thereof.
9. The method of claim 1 , further comprising the step of feeding an aqueous acid solution to the cathode.