METAL FORMATE PRODUCTION
Provided are systems and methods for metal formate synthesis from carbon monoxide supplied by an electrolyzer having a membrane electrode assembly which incorporate the capacity to recover and recycle various chemical components of the production process. For the synthesis, carbon monoxide from an electrolyzer is reacted with a solubilized metal hydroxide in a batch process or a continuous process.
1 . A method of producing a metal formate comprising:
(a) reducing carbon dioxide to carbon monoxide in a carbon dioxide reduction electrolyzer comprising a membrane electrode assembly, which comprises one or more ion conductive polymer layers and a cathode catalyst for facilitating chemical reduction of carbon dioxide to carbon monoxide;
(b) reacting carbon monoxide produced by the carbon dioxide reduction electrolyzer with a metal hydroxide in methanol in at least one formate synthesis reactor to produce a metal formate;
(c) separating and purifying the metal formate produced in (b); and
(d) recycling methanol to the at least one formate synthesis reactor.
2 . The method of claim 1 , wherein the at least one formate synthesis reactor comprises at least two batch formate synthesis reactors and wherein reacting carbon monoxide produced by the carbon dioxide reduction electrolyzer with a metal hydroxide in methanol is performed alternately in the at least two batch formate synthesis reactors.
3 . The method of claim 1 , wherein the at least one formate synthesis reactor comprises at least two batch formate synthesis reactors and wherein reacting carbon monoxide produced by the carbon dioxide reduction electrolyzer with a metal hydroxide in methanol is performed continuously in the at least two batch formate synthesis reactors.
4 . The method of claim 1 , wherein reacting the carbon monoxide with a metal hydroxide takes place at a reaction temperature of about 60° C. to about 200° C., and at a pressure of about 1 MPa to about 10 MPa.
5 . The method of claim 1 , wherein the metal hydroxide has a concentration of about 1 to about 25 percent by weight of metal hydroxide in the methanol.
6 . The method of claim 1 , further comprising pre-heating the carbon monoxide from (a) before reacting in (b).
7 . The method of claim 4 , wherein the carbon monoxide is pre-heated to at least about 100° C.
8 . The method of claim 1 , wherein a reaction temperature is about 100° C. to about 200° C.
9 . The method of claim 1 , further comprising producing methyl formate when reacting carbon monoxide with metal hydroxide in (b).
10 . The method of claim 9 , further comprising recovering the methyl formate by distillation and recycling the methyl formate to the at least one formate synthesis reactor.
11 . The method of claim 1 , wherein (c) comprises drying metal formate with a carrier gas, and producing dry metal formate and a dryer effluent gas stream.
12 . The method of claim 11 , further comprising condensing liquid from the dryer effluent gas stream to form a condensed liquid.
13 . The method of claim 12 , further comprising distilling the condensed liquid to obtain recovered methanol.
14 . The method of claim 13 , wherein recycling methanol to the at least one formate synthesis reactor comprises recycling the recovered methanol to the at least one formate synthesis reactor.
15 . The method of claim 1 , wherein (d) further comprises moisture removal.
16 . The method of claim 12 , further comprising recovering an emitted carrier gas; and recycling the emitted carrier gas to a dryer.
17 . The method of claim 11 , wherein the carrier gas is nitrogen gas.
18 . The method of claim 1 , wherein the metal hydroxide is sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, or a combination thereof.
19 . The method of claim 1 , further comprising converting the metal formate to a metal oxalate.
20 . The method of claim 19 , further comprising contacting the metal oxalate with an acid to produce oxalic acid.