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 .
Election/Restrictions
Applicant’s election without traverse of Group I and with traverse of species (i), claims 1-2 and 4-14, in the reply filed on June 1, 2026 is acknowledged.
The requirement is still deemed proper and is therefore made FINAL.
Accordingly, claims 15-20 (method) are withdrawn from consideration as being directed to a non-elected invention.
Drawings
The drawings were received on May 29, 2025. These drawings are acceptable.
Specification
The disclosure is objected to because of the following informalities:
page 1, [0001], please amend the word “priority” to the word -- benefit --.
Appropriate correction is required.
Claim Objections
Claim 6 is objected to because of the following informalities:
Claim 6
line 2, please insert the word -- the -- before “HBD”.
This is an instance where the article should be added to ensure proper antecedent basis
for the claim terminology.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
Claim 5 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph,
as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 5
line 2, “the cation” lacks antecedent basis.
Antecedent basis must be laid for each recited element in a claim, typically, by introducing each element with the indefinite article (“a” or “an”). See Slimfold Mfg. Co. v. Kincaid Properties, Inc., 626 F. Supp 493, 495 (N.D. Ga. 1985), aff'd, 810 F.2d 1113 (Fed. Cir. 1987) (citing P. Rosenberg, 2 Patent Law Fundamentals § 14.06 (2d. Ed. 1984)). Subsequent mention of an element is to be modified by the definite article “the”, “said” or “the said,” thereby making the latter mention(s) of the element unequivocally referable to its earlier recitation.
line 2, “the anion” lacks antecedent basis.
Antecedent basis must be laid for each recited element in a claim, typically, by introducing each element with the indefinite article (“a” or “an”). See Slimfold Mfg. Co. v. Kincaid Properties, Inc., 626 F. Supp 493, 495 (N.D. Ga. 1985), aff'd, 810 F.2d 1113 (Fed. Cir. 1987) (citing P. Rosenberg, 2 Patent Law Fundamentals § 14.06 (2d. Ed. 1984)). Subsequent mention of an element is to be modified by the definite article “the”, “said” or “the said,” thereby making the latter mention(s) of the element unequivocally referable to its earlier recitation.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
I. Claim(s) 1-2 and 4-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over
Lee et al. (“Deep Eutectic Solvent Formed by Imidazolium Cyanopyrrolide and Ethylene Glycol for Reactive CO2 Separations,” ACS Sustainable Chemistry & Engineering (2021 Jan 14), Vol. 9, No. 3, pp. 1090-1098), Halilu et al. (“Bifunctional Ionic Deep Eutectic Electrolytes for CO2
Electroreduction,” ACS Omega (2022 Oct 12), Vol. 7, No. 42, pp. 37764-37773) and WO 2014/046798 (‘798).
Regarding claim 1, Lee teaches a system (= solvents) [page 1090, abstract] comprising:
• a functionalized ionic liquid (IL) [= a reactive ionic liquid] (page 1090, abstract) that generates ion-CO2 adducts (=
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) and a hydrogen bond donor (HBD) [=
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] upon CO2 absorption (= + CO2) [page 1094, Fig. 1(a)] in a non-aqueous electrolyte, wherein the non-aqueous electrolyte includes the functionalized IL and HBD (= solvents made from a reactive ionic liquid, with an imidazolium cation and pyrrolide anion) [page 1090, abstract].
Lee does not explicitly teach the following:
a. Wherein the system is an electrochemical CO2 reduction system.1
The subject matter would have been obvious to a person having ordinary skill in the art
before the effective filing date of the claimed invention because a preamble is not necessarily accorded any patentable weight where it merely recites the purpose of a process or the intended use of a structure, and where the body of the claim does not depend on the preamble for completeness but, instead, the process steps or structural limitations are able to stand alone. See MPEP § 2111.02.
b. To modulate CO2 reduction reaction (CO₂RR) on a Cu cathode.
The subject matter would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention because the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from the prior art apparatus if the prior art apparatus teaches all the structural limitations of the claim. See MPEP § 2114.
However, Lee teaches a deep eutectic solvent (= Title).
Like Lee, Halilu teaches deep eutectic solvents (= deep eutectic electrolytes) [= Title].
Deep eutectic solvents (DESs) are promising as electrolytes for ECO2R, as they are tunable for task-specific applications.24−31 DESs are simple to prepare, requiring only the mixing of hydrogen bond donor (HBD) and hydrogen bond acceptor(HBA), avoiding any purification of side products.32 So far, there are various cheap and renewable molecules that can serve as HBA or HBD, making DESs a potential and HBD are joined by hydrogen bonds for DESs formation, charge delocalization is imminent, inducing distinct physicochemical features for high CO2 solubility during ECO2R application.33−35 In accordance, non-amine-based DESs used as electrolyte for ECO2R include choline chloride (ChCl) and urea-based DES in water (50wt%)36 and ChCl and ethylene glycol (EG)-based DES37 over Ag electrode. These DESs electrolytes were able to facilitate CO2 conversion to CO, achieving 96 and78% Faradaic efficiency, respectively (pages 37764-37765, bridging paragraph).
Like Halilu, WO ‘798 teaches systems for electrochemical reduction of carbon dioxide (ρ
[0001]).
The present disclosure is directed to a system and method for producing a first product from a first region of an electrochemical cell having a cathode and a second product from a second region of the electrochemical cell having an anode. The method may include the step of contacting the first region of the electrochemical cell with a catholyte comprising carbon dioxide and optionally an alcohol. Another step of the method may include contacting the second region of the electrochemical cell with an anolyte comprising an alcohol. Further, the method may include a step of applying an electrical potential between the anode and the cathode sufficient to produce a first product recoverable from the first region and a second product recoverable from the second region (ρ [0004]).
Reactions occurring at the first region 116 may occur in a catholyte which may include water, methanol, ethanol, acetonitrile, propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, dimethylsulfoxide, dimethylformamide, acetonitrile, acetone, tetrahydrofuran, N,N-dimethylacetamide, dimethoxyethane, diethylene glycol dimethyl ester, butyrolnitrile, 1 ,2-difluorobenzene, γ- butyrolactone, N-methyl-2-pyrrolidone, sulfolane, 1 ,4-dioxane, nitrobenzene, nitromethane, acetic anhydride, ionic liquids, or other catholytes in
which CO2 is soluble. The alcohol source 104 and carbon dioxide source 106 may be configured to supply the carbon-based reactant and carbon dioxide separately or jointly. The alcohol source 104 and carbon dioxide source 106 may be supplied in a solution. The carbon-based reactant source 104 and carbon dioxide source 106 may also be configured to supply the alcohol and carbon dioxide in solution with the catholyte (ρ [0031]).
The cathode may comprise a number of high surface area materials to include copper, stainless steels, carbon, and silicon, which may be further coated with a layer of material which may be a conductive metal or semiconductor (ρ [0049]).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the system taught by Lee with to
modulate CO2 reduction reaction (CO₂RR) on a Cu cathode. The person with ordinary skill in the
art would have been motivated to make this modification because deep eutectic solvents (DESs) are promising as electrolytes for ECO2R, as they are tunable for task-specific applications
as taught by Halilu on page 37764, right column, lines 9-11 where applying an electrical potential between an anode and a copper cathode in an ionic liquid catholyte would have been
sufficient to produce a first product recoverable from the first region as taught by WO ‘798 in
[0001], [0004], [0031] and [0049].
Regarding claim 2, Lee does not explicitly teach an electrochemical cell, wherein the non-aqueous electrolyte and Cu cathode are provided in the electrochemical cell.
WO ‘798 teaches that:
Reactions occurring at the first region 116 may occur in a catholyte which may include water, methanol, ethanol, acetonitrile, propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, dimethylsulfoxide, dimethylformamide, acetonitrile, acetone, tetrahydrofuran, N,N-dimethylacetamide, dimethoxyethane, diethylene glycol dimethyl ester, butyrolnitrile, 1 ,2-difluorobenzene, γ- butyrolactone, N-methyl-2-pyrrolidone, sulfolane, 1 ,4-dioxane, nitrobenzene, nitromethane, acetic anhydride, ionic liquids, or other catholytes in
which CO2 is soluble. The alcohol source 104 and carbon dioxide source 106 may be configured to supply the carbon-based reactant and carbon dioxide separately or jointly. The alcohol source 104 and carbon dioxide source 106 may be supplied in a solution. The carbon-based reactant source 104 and carbon dioxide source 106 may also be configured to supply the alcohol and carbon dioxide in solution with the catholyte (ρ [0031]).
Electrochemical cell 102 is generally operational to reduce carbon dioxide in the first region 116 to a first product 113 recoverable from the first region 116 while producing a second product 115 recoverable from the second region 118. Cathode 122 may reduce the carbon dioxide into a first product 113 that may include one or more compounds. Examples of the first product 113 recoverable from the first region 116 by first product extractor 110 may include carbon monoxide, formic acid, formaldehyde, methanol, oxalate, oxalic acid, glyoxylic acid, glycolic acid, glyoxal, glycolaldehyde, ethylene glycol, acetic acid, acetaldehyde, ethanol, ethylene, methane, ethane, lactic acid, propanoic acid, acetone, isopropanol, 1-propanol, 1,2-propylene glycol, propane, 1-butanol, and 2-butanol (ρ [0012]).
The cathode may comprise a number of high surface area materials to include copper, stainless steels, carbon, and silicon, which may be further coated with a layer of material which may be a conductive metal or semiconductor (ρ [0049]).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the system taught by Lee with an
electrochemical cell, wherein the non-aqueous electrolyte and Cu cathode are provided in the
electrochemical cell. The person with ordinary skill in the art would have been motivated to
make this modification because using the ionic liquid as the catholyte in an electrochemical cell would have been operational to reduce carbon dioxide at a copper cathode in the first region to a first product recoverable from the first region.
Regarding claim 4, Lee teaches wherein the functionalized IL includes a bifunctional IL, the bifunctional IL including a cation (= an imidazolium cation) [page 1090, abstract] and a CO2 chemisorbing anion (= pyrrolide anion) [page 1090, abstract].
Lee does not explicitly teach wherein the cation enhances an electric field to stabilize CO2 between the cation and Cu cathode surface.
The subject matter would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention because Lee teaches the bifunctional IL of at least claims 1 and 4 as applied above. Similar compounds can reasonably be expected to have the same properties.
MPEP § 2141.02(V) states that “from the standpoint of patent law, a compound and all its properties are inseparable in In re Papesch, 315 F.2d 381, 391, 137 USPQ 43, 51 (CCPA 1963).”
Regarding claim 5, Lee teach the combination of the cation and anion (=
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) [page 1094, Fig. 1(a)].
Lee does not explicitly wherein the combination produces the HBD.
The subject matter would have been obvious to a person having ordinary skill in the art
before the effective filing date of the claimed invention because Lee teaches of the cation and anion of at least claim 1 as applied above. Similar compounds can reasonably be expected to have the same properties.
MPEP § 2141.02(V) states that “from the standpoint of patent law, a compound and all its properties are inseparable in In re Papesch, 315 F.2d 381, 391, 137 USPQ 43, 51 (CCPA 1963).”
Regarding claim 6, Lee teaches wherein HBD is formed in situ by absorption of CO2 (= CO2 absorption; and
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[page 1090, abstract].
Regarding claim 7, Lee teaches wherein the bifunctional IL includes an imidazolium-
based cation (= an imidazolium cation) [page 1090, abstract] and a pyrrolide-based anion (= pyrrolide anion) [page 1090, abstract].
Regarding claim 8, Lee teaches wherein the bifunctional IL includes 1-ethyl-3-
methylimidazolium pyrrole-2-carbonitrile ([EMIM][2-CNpyr]) [= [EMIM][2-CNpyr] = 1-ethyl-3-methylimidazolium 2-cyanopyrrolide] (page 1094, Fig. 1(a)).
Regarding claim 9, Lee teaches wherein the non-aqueous electrolyte further includes a non-aqueous diluent in which the bifunctional IL is dissolved, wherein the non-aqueous diluent minimizes mass transfer limitations of the bifunctional IL and increases the ionic conductivity of
the non-aqueous electrolyte (= ethylene glycol) [page 1090, abstract].
Regarding claim 10, Lee teaches wherein the non-aqueous diluent includes acetonitrile or ethylene glycol (= ethylene glycol) [page 1090, abstract].
Regarding claim 11, Lee does not explicitly teach wherein the non-aqueous electrolyte further includes a supporting electrolyte to maintain a stable ionic conductivity of non-aqueous electrolyte.
WO ‘798 teaches that:
The electrolyte may comprise one or more of Na2SO4, KCl, NaNO3, NaCl, NaF, NaClO4, KClO4, K2Sio3, CaCl2, a guanidinium cation, a H cation, an alkali metal cation, an ammonium cation, an alkylammonium cation, a tetraalkyl ammonium cation, a halide anion, an alkyl amine, a borate, a carbonate, a guanidinium derivative, a nitrite, a nitrate, a phosphate, a polyphosphate, a perchlorate, a silicate, a sulfate, and a hydroxide (ρ [0050]).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the non-aqueous electrolyte taught by Lee with wherein the non-aqueous electrolyte further includes a supporting electrolyte. The
person with ordinary skill in the art would have been motivated to make this modification because a tetraalkylammonium perchlorate is an electrolyte2 which would have been used to transported charge between the electrodes to balance chemical reactions and complete the circuit.
As to “to maintain a stable ionic conductivity of non-aqueous electrolyte,” the reason or motivation to modify the reference may often suggest what the inventor has done, but for a
different purpose or to solve a different problem. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant. See MPEP §
2144(IV).
Regarding claim 12, WO ‘798 teaches wherein the supporting electrolyte includes a quaternary ammonium salt (= the electrolyte may include one or more of a tetraalkyl
ammonium cation and a perchlorate) [ρ [0050]].
II. Claim(s) 13 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (“Deep Eutectic Solvent Formed by Imidazolium Cyanopyrrolide and Ethylene Glycol for Reactive CO2 Separations,” ACS Sustainable Chemistry & Engineering (2021 Jan 14), Vol. 9, No. 3, pp. 1090-1098), Halilu et al. (“Bifunctional Ionic Deep Eutectic Electrolytes for CO2
Electroreduction,” ACS Omega (2022 Oct 12), Vol. 7, No. 42, pp. 37764-37773) and WO 2014/046798 (‘798) as applied to claims 1-2 and 4-12 above, and further in view of Rosen et al.
(“Ionic Liquid–Mediated Selective Conversion of CO2 to CO at Low Overpotentials,” Science
(2011 Nov 4), Vol. 334, No. 6056, pp. 643-644).
Regarding claim 13, Lee, Halilu and WO ‘798 teach the system of at least claims 1-2 and 4-12 as applied above. The references do not explicitly teach a voltage source configured to apply a voltage overpotential to the Cu cathode and the non-aqueous electrolyte to implement an electrochemical CO2RR of CO2 on the Cu cathode in the non-aqueous electrolyte.
WO ‘798 teaches that the electrical potential may be a DC voltage (ρ [0011]).
Rosen teaches that:
Electroreduction of carbon dioxide (CO2)—a key component of artificial photosynthesis—has largely been stymied by the impractically high overpotentials necessary to drive the process. We report an electrocatalytic system that reduces CO2 to carbon monoxide (CO) at overpotentials below 0.2 volt. The system relies on an ionic liquid electrolyte to lower the energy of the (CO2)– intermediate, most likely by complexation, and thereby lower the initial reduction barrier. The silver cathode then catalyzes formation of the final products. Formation of gaseous CO is first observed at an applied voltage of 1.5 volts, just slightly above the minimum (i.e., equilibrium) voltage of 1.33 volts. The system continued producing CO for at least 7 hours at Faradaic efficiencies greater than 96% (page 643, abstract).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the system taught by modified Lee with a voltage source configured to apply a voltage overpotential to the Cu cathode and the non-aqueous electrolyte to implement an electrochemical CO2RR of CO2 on the Cu cathode in the non-aqueous electrolyte. The person with ordinary skill in the art would have been motivated to make this modification because using overpotentials below 0.2 volt would have reduced CO2 to carbon monoxide (CO) where an ionic liquid electrolyte lowers the energy of the (CO2)– intermediate, most likely by complexation, and thereby lowers the initial reduction barrier as taught by Rosen on page 643, abstract.
Regarding claim 14, Rosen teaches wherein the applied voltage overpotential is effective to reduce CO2 in the non-aqueous electrolyte to at least one of CO, CH4, C2H4, C₂H₆, formate, succinate, formaldehyde, or butane (= reduces CO2 to carbon monoxide (CO) at overpotentials below 0.2 volt) [page 643, abstract).
Citations
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Dongare et al. (“A Bifunctional Ionic Liquid for Capture and Electrochemical Conversion of CO2 to CO over Silver,” ACS Catalysis (2023 May 25), Vol. 13, No. 12, pp. 7812-7821) is cited to teach Ag electrodes (page 7812, abstract) and that a mixture of 0.1 M TEAP in acetonitrile was used as the supporting electrolyte (page 7814, right column, lines 10-11).
Zhang et al. (“Tuning Functionalized Ionic Liquids for CO2 Capture,” International Journal
of Molecular Sciences (2022 Sep 27), Vol. 23, No. 19, pp. 1-20) is cited to teach the structures of typical cations and anions used for designing functionalized ILs (page 3, Fig. 2).
WO 2010/010252 is cited to teach:
The invention relates to an electrochemical reduction process of carbon dioxide CO2 for the production of formic acid, in which: CO2 is contacted with at least one catholyte of an electrolyzer containing at least one cathode and one catholyte, at least one anode and one anolyte, and at least one separation membrane; CO2 is reduced to formic acid at the cathode, said cathode being a substrate exhibiting low CO2 adsorption, and in which said catholyte is a conductive aprotic medium and said anolyte is a protic medium (ρ [0010]).
Any inquiry concerning this communication or earlier communications from the
examiner should be directed to EDNA WONG whose telephone number is (571) 272-1349. The examiner can normally be reached Monday-Friday, 7:00 AM- 3:30 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Luan Van can be reached at (571) 272-8521. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/EDNA WONG/Primary Examiner, Art Unit 1795
1 Recited in the preamble of claim 1, line 1.
2 An electrolyte is a substance that dissociates into ions in solution, allowing it to conduct electricity.
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