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 .
Claims Status
Claims 1-17 are pending. Claims 1, 3, 5-9, 12-14, 16 and 17 have been amended. Claims 18-28 have been canceled.
Applicant’s arguments, filed 12/02/2025, with respect to rejections under 35 USC 112 have been fully considered and are persuasive. The rejections of claims 5-7 and 10-15 have been withdrawn.
Applicant's arguments filed 12/02/2025 have been fully considered but they are not persuasive. See response to arguments below.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 103
Claim(s) 1 and 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al. (WO 2022155754 A1) in view of Gal et al. (US 7862788 B2).
Considering claim 1, Zhang discloses an electrochemical method for converting captured CO2 into formate (HCOO-) [0011], said method comprising: capturing waste CO2 by co-absorption of the waste CO2 with a strong base (e.g., solution of KOH or NaOH) or an amine-based solvent to form bicarbonate ions [0060] and converting the bicarbonate into formate [0063], wherein said converting is carried out in an integrated flow electrolyzer system [0037].
Zhang further teaches that bicarbonate is ammonium bicarbonate (claim 24).
Zhang also teaches that is conventional to use integrated carbon capture upstream of the electrolyzer to minimize operational cost [0130]. Conventionally, the carbon dioxide is captured in form of for example potassium carbonate and then converted back to a compressed gas, as conventionally the electrolyzers require gaseous CO2 [0130]. The electrolyzer of Zhang bypasses these costly processes of conversion of captured CO2 in liquid form as carbonate and can directly use the bicarbonate solution as the feed for CO2 conversion without the need for regeneration pressurization [0131].
Zhang does not explicitly disclose co-absorption of the waste CO2 with green ammonia (NH3) to form ammonium bicarbonate (NH4HCO3).
However, Gal teaches that ammonium bicarbonate is formed by reacting ammonia with carbon dioxide (col. 3, liens 37-56).
However, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use ammonia as the amine-based solvent to form bicarbonate ions in Zhang, because Zhang disclose the bicarbonate is ammonium bicarbonate and Gal teaches that ammonium bicarbonate is formed by reaction of NH3 with CO2 to form NH4HCO3 for capturing CO2 from waste gas. With respect to the limitation reciting green ammonia, note that green ammonia will have the same composition as ammonia. The term green ammonia does not require any particular method steps of making ammonia, but merely a product-by-process.
It would also have been obvious to have an integrated system of carbon capture with the electrolyzer, because Zhang teaches that such systems CO2RR electrolyzers must be effectively integrated with upstream carbon capture units, and the energy intensive processes like regeneration and pressurization can be omitted and the bicarbonate solution can be directly used in the electrolyzer.
Considering claim 2, in the method of Zhang as modified by Gal, Gal discloses capturing is carried out according to the following formula: CO2 + H2O+ NH3 -> NH4HCO3 (col. 3, liens 37-56).
Claim(s) 1 and 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al. (WO 2022155754 A1) in view of Bedell et al. (US 20140151240 A1).
Considering claim 1, Zhang discloses an electrochemical method for converting captured CO2 into formate (HCOO-) [0011], said method comprising: capturing waste CO2 by co-absorption of the waste CO2 with a strong base (e.g., solution of KOH or NaOH) or an amine-based solvent to form bicarbonate ions [0060] and converting the bicarbonate into formate [0063], wherein said converting is carried out in an integrated flow electrolyzer system [0037].
Zhang further teaches that bicarbonate is ammonium bicarbonate (claim 24).
Zhang also teaches that is conventional to use integrated carbon capture upstream of the electrolyzer to minimize operational cost [0130]. Conventionally, the carbon dioxide is captured in form of for example potassium carbonate and then converted back to a compressed gas, as conventionally the electrolyzers require gaseous CO2 [0130]. The electrolyzer of Zhang bypasses these costly processes of conversion of captured CO2 in liquid form as carbonate and can directly use the bicarbonate solution as the feed for CO2 conversion without the need for regeneration pressurization [0131].
Zhang does not explicitly disclose co-absorption of the waste CO2 with green ammonia (NH3) to form ammonium bicarbonate (NH4HCO3) in an integrated system.
However, Bedell teaches an integrated system of carbon capture using ammonia with forms ammonium bicarbonate by reacting ammonia with carbon dioxide ([0014], [0019], [0030] and [0035]).
However, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use ammonia as the amine-based solvent to form bicarbonate ions in Zhang, because Zhang disclose the bicarbonate is ammonium bicarbonate and Bedell teaches that ammonium bicarbonate is formed by reaction of NH3 with CO2 to form NH4HCO3 for capturing CO2 from waste gas, and it can be used in a solution form in an CO2RR electrolyzer.
Considering claim 2, in the method of Zhang as modified by Gal, Gal discloses capturing is carried out according to the following formula: CO2 + H2O+ NH3 -> NH4HCO3 [0019].
Claim(s) 3, 4 and 6-14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, and Gal et al., as applied to claims 1-2 above, and further in view of McEnaney et al. (US 20210301408 A1).
Considering claims 3 and 4, Zhang does not disclose an alkaline electrolyzer for producing NH3 from NO3-.
However, McEnaney discloses an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium [0036].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium in the system of Zhang as modified by Gal, because Zhang only generally discloses using ammonia McEnaney teaches how to make ammonia using an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium.
Considering claim 6, in the method of Zhang and Gal as modified by McEnaney, McEnaney discloses the anode and the cathode comprise nickel, which may be porous [0027].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the nickel anode and cathode in a form of wire mesh, because McEnaney teaches that the electorate may be porous, and a porous metal electrodes in a form of wire mesh are well-known in the art.
Considering claim 7, in the method of Zhang and Gal as modified by McEnaney, McEnaney discloses, diffusion barrier or membrane is optional (Fig. 1), therefore McEnaney teaches the alkaline electrolyzer has no membrane between the anode and the cathode.
Considering claim 8, Zhang discloses the integrated flow electrolyzer system comprises an CO2 absorbing unit forming carbonate wherein said capturing is carried out (Fig. 11B) and Gal discloses in the method of Zhang as modified by Gal, Gal discloses capturing is carried out according to the following formula: CO2 + H2O+ NH3 -> NH4HCO3 (col. 3, liens 37-56). Therefore, the absorbing unit of Zhang as modified by Gal is an NH3-CO2 absorbing unit.
Considering claim 9, Zhang discloses the integrated flow electrolyzer comprises a bicarbonate electrolyzer for carrying out said converting ([0060]-[0063]).
Considering claim 10, Zhang discloses the integrated flow electrolyzer comprises a bicarbonate electrolyzer for carrying out said converting [0007].
Considering claim 11, Zhang as modified by Gal discloses the bicarbonate electrolyzer further comprises: a reaction medium comprising ammonium bicarbonate (NH4HCO3) (Claim 24); and a power supply operably connected to the anode and the cathode [0018].
Considering claims 12 and 13, Zhang discloses the anode comprises nickel foam [0115].
Considering claim 14, Zhang discloses the cathode comprises GDE coated with Bi [0138].
Zhang is silent about the coating method.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to electrodeposit coat the GDE with Bi, because electrodeposition is a common metallization technique for conformally coating complex porous structures.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, Gal et al. and McEnaney et al. as applied to claim 14 above, and further in view of Chen et al. (“Revealing nitrogen-containing species in commercial catalysts used for ammonia electrosynthesis”, Nat Catal 3, 1055–1061 ‘2020’).
Considering claim 5, Zhang does not disclose the reaction medium comprises a concentrated NaOH-KOH solution.
However, Chen teaches that H2O-NaOH-KOH system exhibited the efficacy to reduce NOx- to NH3 with ~100% selectivity (last page, 1st paragraph).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have a NaOH-KOH solution in the alkaline electrolyzer of Zhang, because Chen teaches that H2O-NaOH-KOH system exhibited the efficacy to reduce NOx- to NH3 with ~100% selectivity.
Claim(s) 15-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, Gal et al. and McEnaney et al. as applied to claim 14 above, and further in view of Schmid et al. (US 20210180196 A1).
Considering claim 15, Zhang discloses the cathode is formed on carbon cloth ([0138] and [0151]).
Zhang does not disclose the cathode is formed on carbon paper.
However, Schmid teaches a gas diffusion electrode or porous bound catalyst structure, may be a porous, conductive, catalytically inactive structure, e.g. a carbon-paper GDL (gas diffusion layer), a carbon-cloth GDL [0050].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the carbon cloth of Zhang for carbon paper of Schmid as functional equivalents, because Schmid teaches a gas diffusion electrode or porous bound catalyst structure, may be a porous, conductive, catalytically inactive structure, e.g. a carbon-paper GDL (gas diffusion layer), a carbon-cloth GDL.
Considering claims 16 and 17, Zhang discloses said converting is carried out at a temperature of between 60-80°C [0013], which overlaps the claimed ranges of 35- 80°C and also 40-60°C.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the recited range because a prima facie case of obviousness exists in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). Furthermore, "[ A ] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See MPEP 2144.05.
Claim(s) 3, 4 and 6-14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, and Bedell et al., as applied to claims 1-2 above, and further in view of McEnaney et al. (US 20210301408 A1).
Considering claims 3 and 4, Zhang does not disclose an alkaline electrolyzer for producing NH3 from NO3-.
However, McEnaney discloses an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium [0036].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium in the system of Zhang as modified by Gal, because Zhang only generally discloses using ammonia McEnaney teaches how to make ammonia using an alkaline electrolyzer for producing NH3 from NO3- comprising an anode, a cathode and a reaction medium.
Considering claim 6, in the method of Zhang and Bedell as modified by McEnaney, McEnaney discloses the anode and the cathode comprise nickel, which may be porous [0027].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the nickel anode and cathode in a form of wire mesh, because McEnaney teaches that the electorate may be porous, and a porous metal electrodes in a form of wire mesh are well-known in the art.
Considering claim 7, in the method of Zhang and Bedell as modified by McEnaney, McEnaney discloses, diffusion barrier or membrane is optional (Fig. 1), therefore McEnaney teaches the alkaline electrolyzer has no membrane between the anode and the cathode.
Considering claim 8, Zhang discloses the integrated flow electrolyzer system comprises an CO2 absorbing unit forming carbonate wherein said capturing is carried out (Fig. 11B) and Bedell discloses in the method of Zhang as modified by Gal, Gal discloses capturing is carried out according to the following formula: CO2 + H2O+ NH3 -> NH4HCO3 [0019]. Therefore, the absorbing unit of Zhang as modified by Gal is an NH3-CO2 absorbing unit.
Considering claim 9, Zhang discloses the integrated flow electrolyzer comprises a bicarbonate electrolyzer for carrying out said converting ([0060]-[0063]).
Considering claim 10, Zhang discloses the integrated flow electrolyzer comprises a bicarbonate electrolyzer for carrying out said converting [0007].
Considering claim 11, Zhang as modified by Bedell discloses the bicarbonate electrolyzer further comprises: a reaction medium comprising ammonium bicarbonate (NH4HCO3) (Claim 24); and a power supply operably connected to the anode and the cathode [0018].
Considering claims 12 and 13, Zhang discloses the anode comprises nickel foam [0115].
Considering claim 14, Zhang discloses the cathode comprises GDE coated with Bi [0138].
Zhang is silent about the coating method.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to electrodeposit coat the GDE with Bi, because electrodeposition is a common metallization technique for conformally coating complex porous structures.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, Bedell et al. and McEnaney et al. as applied to claim 14 above, and further in view of Chen et al. (“Revealing nitrogen-containing species in commercial catalysts used for ammonia electrosynthesis”, Nat Catal 3, 1055–1061 ‘2020’).
Considering claim 5, Zhang does not disclose the reaction medium comprises a concentrated NaOH-KOH solution.
However, Chen teaches that H2O-NaOH-KOH system exhibited the efficacy to reduce NOx- to NH3 with ~100% selectivity (last page, 1st paragraph).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have a NaOH-KOH solution in the alkaline electrolyzer of Zhang, because Chen teaches that H2O-NaOH-KOH system exhibited the efficacy to reduce NOx- to NH3 with ~100% selectivity.
Claim(s) 15-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al, Bedell et al. and McEnaney et al. as applied to claim 14 above, and further in view of Schmid et al. (US 20210180196 A1).
Considering claim 15, Zhang discloses the cathode is formed on carbon cloth ([0138] and [0151]).
Zhang does not disclose the cathode is formed on carbon paper.
However, Schmid teaches a gas diffusion electrode or porous bound catalyst structure, may be a porous, conductive, catalytically inactive structure, e.g. a carbon-paper GDL (gas diffusion layer), a carbon-cloth GDL [0050].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the carbon cloth of Zhang for carbon paper of Schmid as functional equivalents, because Schmid teaches a gas diffusion electrode or porous bound catalyst structure, may be a porous, conductive, catalytically inactive structure, e.g. a carbon-paper GDL (gas diffusion layer), a carbon-cloth GDL.
Considering claims 16 and 17, Zhang discloses said converting is carried out at a temperature of between 60-80°C [0013], which overlaps the claimed ranges of 35- 80°C and also 40-60°C.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the recited range because a prima facie case of obviousness exists in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). Furthermore, "[ A ] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See MPEP 2144.05.
Response to Arguments
Applicant's arguments filed 12/02/2025 have been fully considered but they are not persuasive. Applicant argues that Zhang and Gal cannot be combined because Gal discloses chilled ammonia scrubbing, which require low-temperature conditions and high solvent concentration, which is incompatible with Zhang’s electrolyzer because the ratio of NH3/CO2 > 1, leading to pH of 11-12 and in Zhang the pH is 8-10, furthermore Gal also uses a promotor (piperazine). Applicant thus alleges that this could lead to poisoning of the catalyst. The arguments are not persuasive, because Gal also teaches a conventional method where ammonia is used without the promotor as conventional, and the methods of adjusting pH are well within the scope of an ordinary skill in the art. With respect to the argument that it would not be obvious to use ammonium bicarbonate in Zheng, please note that Zheng explicitly teaches such alternative (see rejection above).
With respect to arguments of unexpected results, Applicant points to table 2 of the present specification. The table shows that at certain conditions of current density and temperature the FE for production of format is higher for NH4HCO3, vs KHCO3, however no such conductions are claimed. Therefore, the scope of the showing is not commensurate with the scope of the claims. Furthermore, the structure of the electrolytic cell has a significant effect on FE, for example a choice of membrane (CEM, AEM or BEM).
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., current density or temperature) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
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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/WOJCIECH HASKE/Examiner, Art Unit 1794