DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendments
This is a final office action in response to applicant's arguments and remarks filed on 05/18/2026.
Status of Rejections
The objections to the claims are withdrawn in view of applicant’s amendments.
All previous rejections are withdrawn in view of applicant’s amendments.
New grounds of rejection are necessitated by applicant’s amendments.
Claims 1-12 and 31-32 are pending and under consideration for this Office Action.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-8, 10-12 and 31-32 are rejected under 35 U.S.C. 103 as being unpatentable over Asanin et al. (DE 102016211155 A1, citations based on translation) in view of Kudo et al. (U.S. 2018/0274109), and further in view of Uddin et al. (“Effect of hydrophobicity of gas diffusion layer in calcium cation contamination in polymer electrolyte fuel cells”, Int J Hydrogen Energy, 2016).
Regarding claim 1, Asanin discloses a process to enhance electrolyser performance of an electrolyser for continuous electrolysis of gaseous carbon dioxide, CO2 (see e.g. Paragraphs 0014 and 0018, method for improved long-term, continuous operation of an arrangement for carbon dioxide electrolysis), said electrolyser comprising at least an anode with an anode catalyst layer (see e.g. Fig. 2, anode 13 of electrolysis cell 11 as counter electrode comprising platinum or iridium mixed oxide coating, i.e. catalyst layer; Paragraph 0008, line 1, and Paragraph 0023, lines 3-4), a cathode with a cathode catalyst layer formed as a gas-diffusion electrode, GDE (see e.g. Fig. 2, cathode 15 as gas diffusion electrode with applied catalyst; Paragraph 0026, lines 1-2), an ion-conducting separator layer arranged between the anode and the cathode (see e.g. Fig. 2, ion exchange membrane 21 between anode 13 and cathode 15; Paragraph 0006, lines 4-5, and Paragraph 0023, lines 5-6), an anode compartment formed in contact with the anode (see e.g. Fig. 2, anode space/compartment 12 adjacent anode 13; Paragraph 0023, lines 3-6), and a cathode compartment formed in contact with the cathode (see e.g. Fig. 2, gas space 16 adjacent cathode 15; Paragraph 0026, lines 5-6), said process comprising:
directing a flow of gaseous CO2 through the cathode compartment (see e.g. Fig. 2, CO2 introduced into gas space 16 via carbon dioxide inlet 24; Paragraph 0026, lines 3-4), directing a flow of anolyte through the anode compartment (see e.g. Fig. 2, electrolyte flowing in and out of anode compartment 12 through respective inlet and outlet; Paragraph 0024, lines 5-8), and performing electrolysis of said CO2 in the electrolyser, thereby conversing said CO2 into at least one product leaving said electrolyser (see e.g. Paragraph 0024, lines 10-11, and Paragraph 0026, lines 4-6, CO2 reacts at cathode to form electrolysis products which leave through a product outlet), and
directing a liquid flow containing alkali metal cations through the cathode compartment on a gas side of said cathode (see e.g. Fig. 2, electrolyte containing potassium or other alkali metal salt ions as washing liquid pumped into gas space 16; Paragraph 0029, lines 4-7), the liquid flow being also wetting the GDE, thereby activating the GDE (see e.g. Paragraph 0018, Paragraph 0019, lines 18-19, and Paragraph 0029, lines 6-7, electrolyte wets cathode, dissolving and transporting away formed carbonate salts, thereby cleaning and unclogging, i.e. activating, the cathode).
Asanin does not explicitly teach the ion-conducting separator layer comprising an anion-conducting substance, but does generally teach it comprising an ion exchange membrane (see e.g. Paragraph 0006, lines 4-5) and an alkaline hydroxide solution being used as an electrolyte (see e.g. Paragraph 0009, lines 3-4).
Kudo teaches a carbon dioxide electrolytic device (see e.g. Abstract) comprising a separator constituted of an ion exchange membrane separating an anode part and a cathode part (see e.g. Paragraph 0041, lines 1-4), the separator preferable being constituted of an anion exchange membrane with an alkaline solution containing hydroxide ions is used as an anode or cathode solution (see e.g. Paragraph 0041, lines 7-11).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ion-conducting separator of Asanin to comprise an anion exchange, i.e. anion-conducting, membrane as taught by Kudo as a preferable type of ion exchange membrane for use in a carbon dioxide electrolytic device with alkaline hydroxide as an electrolyte solution. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results. Further, MPEP § 2144.07 states “The selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945)”.
Modified Asanin does not explicitly teach a composition of the liquid flow being tailored to a degree of hydrophobicity of the GDE to induce the wetting. Asanin does however teach the desire for the liquid flow to wet the cathode GDE and particularly washing away salt that could clog the pores of the GDE (see e.g. Asanin Paragraph 0018, Paragraph 0019, lines 18-19, and Paragraph 0029, lines 6-7, electrolyte wets cathode, dissolving and transporting away formed carbonate salts, thereby cleaning and unclogging, i.e. activating, the cathode).
Uddin teaches a gas diffusion layer of a membrane electrode assembly (see e.g. Abstract) wherein a solution is provided, particularly with a solvent composition of 25% isopropanol in DI water by volume, that wets the gas diffusion layer and renders it hydrophilic, overcoming its hydrophobic nature (see e.g. Abstract and connecting paragraph of Pages 14912-14913), such sufficiently high concentration of wetting agent being usable for removing cations, i.e. salts from the CCM of the membrane electrode assembly (see e.g. Page 14915, Summary and conclusions, lines 9-14).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the liquid flow of modified Asanin to have a solvent composition of 25% isopropanol in water by volume as taught by Uddin as a suitable composition for wetting the surface of an electrode gas diffusion layer that would thereby facilitate removal of salts in the pores thereof.
Regarding claim 2, modified Asanin teaches the liquid flow containing alkali metal cations being a liquid flow of at least one promoter, said at least one promoter being KOH (see e.g. Asanin Paragraph 0009, lines 3-4, and Paragraph 0029, lines 4-7, electrolyte comprising KOH as washing liquid).
Regarding claim 3, Asanin as modified by Kudo above does not explicitly teach the at least one promoter having a concentration in said liquid flow of 0.001 to 5 mol/dm3. Asanin does however teach the liquid flow being an electrolyte solution containing KOH (see e.g. Asanin Paragraph 0009, lines 3-4, and Paragraph 0029, lines 4-7, electrolyte comprising KOH as washing liquid).
Kudo further teaches the CO2 electrolytic device utilizing a high concentration 1 M, equal to 1 mol/dm3, aqueous KOH solution as the anode and cathode electrolyte solutions to provide reduced electrical resistance (see e.g. Kudo Paragraph 0042, lines 7-22, and Paragraph 0084, lines 1-10).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the liquid flow of modified Asanin to comprise 1 mol/dm3 of the KOH promoter as taught by Asanin as a suitable high concentration of KOH for use as an electrolyte solution in a carbon dioxide electrolytic device that provides reduced electrical resistance. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results.
Regarding claim 4, modified Asanin teaches a total volume of the liquid flow directed through the cathode compartment being less than 1 times an empty volume of said cathode compartment (see e.g. Asanin Paragraph 0031, flow of washing liquid prevented from filling up gas space, i.e. being less than the total empty volume), overlapping the claimed range of the present invention.
MPEP § 2144.05 I states “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.”
Regarding claim 5, Asanin as modified by Uddin teaches providing said liquid flow capable of wetting the GDE as a solvent mixture of two different solvents (see e.g. Uddin connecting paragraph of Pages 14912-14913, isopropanol, i.e. 2-propanol, in DI water).
Regarding claim 6, Asanin as modified by Uddin teaches selecting solvents from a group of water, deionized water and 2-propanol (see e.g. Uddin connecting paragraph of Pages 14912-14913, isopropanol, i.e. 2-propanol, in DI water).
Regarding claim 7, modified Asanin teaches using said liquid flow capable of wetting the GDE for dissolving said at least one promoter (see e.g. Asanin Paragraph 0009, lines 3-4, and Paragraph 0029, lines 4-7, electrolyte comprising dissolved KOH salt as washing liquid wetting the cathode).
Regarding claim 8, Asanin as modified by Kudo above does not explicitly teach the at least one promoter having a concentration in said liquid flow of 0.001 to 5 mol/dm3. Asanin does however teach the anolyte comprising a liquid containing an alkaline material (see e.g. Asanin Paragraph 0009, lines 3-4, electrolyte comprising alkaline KOH).
Kudo further teaches the CO2 electrolytic device utilizing a high concentration 1 M aqueous KOH solution as the anode and cathode electrolyte solutions to provide reduced electrical resistance (see e.g. Kudo Paragraph 0042, lines 7-22, and Paragraph 0084, lines 1-10).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the anolyte of modified Asanin to comprise 1 M KOH as taught by Asanin as a suitable high concentration of KOH for use as an electrolyte solution in a carbon dioxide electrolytic device that provides reduced electrical resistance. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results.
Regarding claim 10, modified Asanin teaches an alkali-metal containing solution being applied as the electrolyte (see e.g. Asanin Paragraph 0009, lines 3-4, electrolyte comprising KOH).
Regarding claim 11, modified Asanin teaches directing said liquid flow through the cathode compartment simultaneously with the flow of gaseous CO2 (see e.g. Asanin Paragraph 0018 and Paragraph 0026, lines 3-6, electrolysis, and therefore introduction of CO2, operated continuously and uninterrupted along with the application of the washing liquid).
Regarding claim 12, modified Asanin teaches said electrolyser being a single electrolyser cell (see e.g. Asanin Fig. 2, electrolysis cell 11; Paragraph 0023, lines 1-2).
Regarding claim 31, Asanin as modified by Uddin teaches the liquid flow being a solvent mixture of 2-propanol and deionized water with a volume ratio of 1:3 (see e.g. Uddin connecting paragraph of Pages 14912-14913, 25% isopropanol, i.e. 2-propanol, in DI water by volume).
Regarding claim 32, Asanin as modified above does not teach the electrolyser being configured as a zero-gap electrolyser cell. Asanin does teach the process serving to wash the cathode surface and remove precipitated salts from the electrolyte (see e.g. Asanin Paragraphs 0009 and 0018, and Paragraph 0019, lines 18-19).
Kudo further teaches an embodiment of an electrolysis cell for CO2 reduction provided with a cathode and anode in contact with either side of a separator, thereby having a zero-gap configuration (see e.g. Kudo Fig. 14, anode 11 and cathode 22 in contact with separator 30; Paragraph 0075, lines 1-4 and 11-13), with cathode and anode flow paths in contact with the respective electrodes (see e.g. Kudo Fig. 14, CO2 gas flow path 23 and anode solution flow path 12; Paragraph 0075, lines 1-3 and 11-13), wherein a rinse solution may be supplied to said flow paths to wash the electrodes and remove electrolyte precipitates (see e.g. Kudo Paragraph 0078, lines 4-7, and Paragraph 0079, lines 5-12).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of modified Asanin to be applied with an electrolysis cell having a zero-gap configuration as taught by Kudo as an alternate suitable electrolysis cell configuration for CO2 reduction that would benefit from the GDE cathode washing and salt removal process. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results. Further, MPEP § 2143(I)(B) states that “simple substitution of one known element for another to obtain predictable results” may be obvious.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Asanin, Kudo and Uddin, as applied to claim 8 above, and further in view of Kaczur et al. (U.S. 2017/0037522).
Regarding 9, modified Asanin teaches all the elements of the process of claim 9 as stated above. Modified Asanin does not teach pure de-ionized water being applied as the anolyte. Asanin does however teach water being the only reactant for the anode reaction (see e.g. Asanin Paragraph 0010), and Kudo teaches that the anode and cathode solutions may be different, as long as they preferably contain at least water (see e.g. Kudo Paragraph 0042, lines 1-7).
Kaczur teaches an electrochemical device for conversion of carbon dioxide (see e.g. Abstract), wherein an anolyte solution to be introduced into an anode compartment can be deionized water (see e.g. Paragraphs 0223).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the anolyte of modified Asanin to be deionized water as taught by Kaczur as a suitable solution comprising water to be used as an anolyte solution in an electrochemical carbon dioxide conversion device. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results. Further, MPEP § 2144.07 states “The selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945)”.
Response to Arguments
Applicant’s arguments, see pages 9-11, filed 05/18/2026, with respect to the rejection(s) of claim(s) 1 under 35 USC 103 over Asanin in view of Kudo, particularly regarding the composition being tailored for the hydrophobicity of the GDE, have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Asanin, Kudo and Uddin.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/M.S.J./Examiner, Art Unit 1795
/LUAN V VAN/Supervisory Patent Examiner, Art Unit 1795
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