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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on April 28, 2026 has been entered.
This is in response to the Amendment dated April 28, 2026. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Response to Amendment
Claim Rejections - 35 USC § 112
Claims 19-22, 25, 27, 30-37 and 39-43 have been rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time
the application was filed, had possession of the claimed invention.
The rejection of claims 19-22, 25, 27, 30-37 and 39-43 has been withdrawn in view of Applicant’s amendment.
Claim Rejections - 35 USC § 103
I. Claim(s) 19, 25, 27, 37, 40-41 and 43 stand rejected under 35 U.S.C. 103 as being
unpatentable over WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938).
Regarding claim 19, WO ‘447 teaches a method for generating one or more carbon products, comprising:
(a) providing a stream comprising carbon dioxide (CO2) [= the CO2-containing gas (14)]
(page 12, line 11; and Fig. 1);
(b) in a contactor, contacting said stream with an electrolyte solution to capture at least a subset of said CO2 from said stream into said electrolyte solution (= the CO2 capture unit or absorption unit (10) can be a gas/liquid contactor where the CO2-containing gas (14) can be contacted with an aqueous absorption solution (16)) [page 12, lines 10-12], thereby obtaining one or more carbonate or bicarbonate ions (= upon contacting the CO2-containing gas with the
absorption solution, the CO2 is dissolved or absorbed in the aqueous absorption solution and
then transformed, at least partially, into bicarbonate ions (HCO3-)) [page 12, lines 12-15];
(c) directing said electrolyte solution to an electrochemical stack (= the conversion
experiments were conducted using the Berlinguette Flow Cell as described in WO 2019/051609, developed by the Berlinguette group at University of British Columbia) [page 21, lines 19-21] comprising an anode (= the anode) and a cathode (= the cathode) [page 20, lines 9-13], wherein said electrolyte solution comprises said one or more carbonate or bicarbonate ions (= the aqueous absorption solution containing the bicarbonate ions (20) can then be pumped through a pump (22) towards the conversion unit (12). The conversion unit (12) comprises an electrolytic cell) [page 12, lines 18-20]; and
(d) while a voltage is applied between said anode and said cathode (= the experiments
were conducted at a temperature of 25°C at a voltage ranging from 3 to 3.5 V) [page 21, lines 21-22] reducing said one or more carbonate or bicarbonate ions to generate said one or more carbon products (= in the electrolytic cell, the bicarbonate ions present in the bicarbonate loaded aqueous solution (20) can be transformed into a gaseous stream comprising CO and H2 (28)) [page 12, lines 21-23].
WO ‘447 does not explicitly teach the following:
a. Wherein the stream is an atmospheric air stream.
b. Wherein said atmospheric air stream is not from an industrial source.
WO ‘447 teaches:
Contacting a CO2-containing gas with an aqueous absorption solution
to produce a bicarbonate loaded stream and a CO2-depleted gas (page 2, lines 24-25).
In some implementations of the process, the aqueous absorption solution can comprise an absorption compound selected from the group consisting of sodium carbonate and potassium carbonate, or any mixture thereof (page 3, lines 12-14).
According to some embodiments, the CO2-containing gas can be a power and/or steam plant
flue gas, an industrial exhaust gas, or a chemical production flue gas. In some embodiments, the CO2-containing gas can be a flue gas from a coal power and/or steam station, a flue gas from a gas power and/or steam station, a flue gas from metals production, a flue gas from a cement
plant, a flue gas from a pulp and paper mill, an emission from lime kilns, a flue gas from a bicarbonate unit or a flue gas from a soda ash mill (page 11, line 26, to page 12, line 2).
Olah teaches that:
The present invention discloses an environmentally harmonious and efficient method of converting any carbon dioxide source to methanol. Suitable carbon dioxide sources can be industrial exhaust streams from hydrocarbon (fossil fuel) burning power plants, cement plants natural gas wells, and the like, as well as the atmosphere. The use of this process of converting carbon dioxide to methanol and/or dimethyl ether and their products will also lead to a significant reduction of carbon dioxide, a major greenhouse gas, in the atmosphere thus mitigating global warming (page 6-7, [0054])
The capture and use of existing atmospheric CO2 allows chemical recycling of CO2 as a
renewable and unlimited source of carbon. CO2 absorption facilities can be placed proximate to a hydrogen production site to enable subsequent methanol synthesis. Although the CO2 content in the atmosphere is low (only 0.037%), the atmosphere offers an abundant and unlimited supply because CO2 is recycled. For using atmospheric carbon dioxide efficiently, CO2 absorption facilities are needed. This can be addressed by using efficient CO2 absorbents such as polyethyleneimines, polyvinylpyridines, polyvinylpyrroles, etc., on suitable solid carriers (e.g., active carbon, polymer, silica or alumina), which allow absorption of even the low concentration of atmospheric CO2. CO2 can also be captured using basic absorbents such as calcium hydroxide (Ca(OH)2) and potassium hydroxide (KOH), which react with CO2 to form calcium carbonate (CaCO3) and potassium carbonate (K2CO3), respectively. CO2 absorption is an exothermic reaction, which liberates heat, and is readily achieved by contacting CO2 with an adequate base (page 8, [0076]).
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 stream taught by WO ‘447 with wherein the stream is an atmospheric air stream and wherein said atmospheric air stream is
not from an industrial source. The person with ordinary skill in the art would have been motivated to make this modification because WO ‘447 teaches that the CO2-containing gas is an
industrial exhaust gas on page 11, line 26-27, where the atmosphere is an alternative to industrial exhaust streams as a carbon dioxide source as taught by Olah in [0054] and where the capture and use of existing atmospheric CO2 would have allowed chemical recycling of CO2 as a renewable and unlimited source of carbon as taught by Olah in [0076].1
Furthermore, the substitution of art recognized equivalents as shown by Olah in [0054] is within the level of ordinary skill in the art. In addition, the substitution of one carbon dioxide source for another is likely to be obvious when it does nothing more than yield predictable results.
c. Wherein in (d), a total concentration of said one or more carbonate or bicarbonate ions in said electrolyte solution is no more than 2.0 M.
WO ‘447 teaches that:
Upon conversion of the bicarbonate ions in the conversion unit, where the bicarbonate ions are converted into CO and H2, the bicarbonate/carbonate ratio is then reduced and, in some embodiments, the stream exiting the conversion unit can present a bicarbonate/carbonate ratio which can be close or substantially similar to the bicarbonate/carbonate ratio in the initial stream (16) which was treated in the absorption unit. For example, if stream (16) contained bicarbonate/carbonate ions in a ratio of 1 and that after absorption of the CO2 in the absorption unit, the ratio in stream (20) is 8, one can expect, in some embodiments, to return to a ratio of 1, or close to 1, at the exit of the conversion unit once the bicarbonate ions have been converted into CO and H2 (page 14, lines 12-21).
When the absorption compound is sodium carbonate, the sodium carbonate solution can have a sodium concentration ranging from 0.5 to 2 mol/l. In some embodiments, the sodium carbonate absorption solution can have a sodium concentration ranging from 0.5 to 1.5 mol/l, or from 0.5 to 1 mol/l, or from 1 to 2 mol/l, or from 1 to 1.5 mol/l, or from 1.5 to 2 mol/l. The CO2 loading of the absorption solution entering the gas/liquid absorption unit can range from 0.5 to 0.75 mol C/mol Na+, or from 0.5 to 0.7 mol C/mol Na+, or from 0.6 to 0.7 mol C/mol Na+. Furthermore, the CO2 loading of the absorption solution leaving the gas/liquid absorption unit
can range from 0.75 to 1 mol C/mol Na+, or from 0.75 to 0.9 mol C/mol Na+, or from 0.75 to 0.8 mol C/mol Na+, or from 0.8 to 0.95 mol C/mol Na+ (page 18, lines 11-19).
When the absorption compound is potassium carbonate, the potassium carbonate solution can have a potassium concentration ranging from 1 to 6 mol/l. In some embodiments, the potassium carbonate absorption solution can have a potassium concentration ranging from 1 to 5 mol/l, or from 1 to 4 mol/l, or from 1 to 3 mol/l, or from 1 to 2 mol/l, or from 2 to 6 mol/l, or from 2 to 5 mol/l, or from 2 to 4 mol/l, or from 2 to 3 mol/l, or from 3 to 6 mol/l, or from 3 to 5 mol/l, or from 3 to 4 mol/l, or from 4 to 6 mol/l, or from 4 to 5 mol/l, or from 5 to 6 mol/l. The CO2 loading of the absorption solution entering the gas/liquid absorption unit can range from 0.5 to 0.75 mol C/mol K+, or from 0.5 to 0.7 mol C/mol K+, or from 0.6 to 0.7 mol C/mol K+. Furthermore, the CO2 loading of the absorption solution leaving the gas/liquid absorption unit can range from 0.75 to 1 mol C/mol K+, or from 0.75 to 0.9 mol C/mol K+, or from 0.75 to 0.8 mol C/mol K+, or from 0.8 to 0.95 mol C/mol K+ (page 18, lines 20-30).
WO ‘938 teaches that:
One aspect of the invention provides a carbon capture method comprising chemically reacting gaseous carbon dioxide to form bicarbonate and/or carbonate in an aqueous solution. The aqueous solution is supplied at a cathode of an electrochemical reactor comprising an anode and the cathode separated by a bipolar membrane. A potential difference is applied between the anode and the cathode to cause an electrochemical reaction yielding product gas comprising one or both of gas phase carbon dioxide and gas phase carbon monoxide. The product gas is subsequently separated from the aqueous solution (ρ [0009]).
The aqueous solution precipitates a carbonate and/or bicarbonate after contacting the gas in some embodiments. The concentration of carbonate and/or bicarbonate ions in the aqueous solution may, for example, be in the range of 0.5M to 3M (ρ [0015]).
The subject matter would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention because WO ‘447 teaches that upon conversion of the bicarbonate ions in the conversion unit,2 the stream exiting the conversion unit can present a bicarbonate/carbonate ratio which can be close or substantially similar to the bicarbonate/carbonate ratio in the initial stream which was treated in the absorption unit
on page 14, lines 12-17, where when the absorption compound is sodium carbonate, the sodium carbonate solution can have a sodium concentration ranging from 0.5 to 2 mol/l (page 18, lines 11-12) and when the absorption compound is potassium carbonate, the potassium carbonate solution can have a potassium concentration ranging from 1 to 6 mol/l (page 18, lines 20-21).
Thus, the total concentration of said one or more carbonate or bicarbonate ions in said electrolyte solution exiting the conversion unit would have included a total concentration ranging from 0.5 to 2 mol/l.
Regarding claim 25, WO ‘447 teaches wherein said cathode comprises a catalyst (= the cathode can comprise a silver-coated carbon gas diffusion layer) [page 20, line 11].
Regarding claim 27, WO ‘447 teaches wherein said catalyst comprises one or more
metals selected from the group consisting of copper, nickel, platinum, iridium, ruthenium,
palladium, tin, silver, and gold (= the cathode can comprise a silver-coated carbon gas diffusion
layer) [page 20, line 11].
Regarding claim 37, WO ‘447 does not explicitly teach wherein said one or more carbon products comprise ethanol.
The subject matter would have been obvious to one having ordinary skill in the art
before the effective filing date of the claimed invention because WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claim 19 as applied above. Hence, similar processes can reasonably be expected to yield products which inherently have the same properties. In re Spada 911 F.2d 705, 15 USPQ 2d 1655 (CAFC 1990); In re DeBlauwe 736 F.2d
699, 222 USPQ 191 (CAFC 1984); In re Wiegand 182 F.2d 633, 86 USPQ 155 (CCPA 1950).
A process yielding an unobvious product may nonetheless be obvious where Applicant claims a process in terms of function, property or characteristic and the process of the prior art
is the same or similar as that of the claim but the function is not explicitly disclosed by the
reference. See MPEP § 2116.01.
Regarding claim 40, WO ‘447 teaches wherein in (d), said cathode operates at a current density of at least 100 mA/cm2 (= in some implementations of the process, the electrochemical conversion can be conducted at a current density ranging from 20 to 200 mA۰cm-2) [page 6,
lines 15-16].
Regarding claim 41, WO ‘447 teaches wherein said electrochemical stack comprises a
bipolar membrane positioned between said anode and said cathode (= in some embodiments,
the electrolytic cell can be a bipolar membrane-based electrolytic cell (page 20, lines 9-10); and
the conversion experiments were conducted using the Berlinguette Flow Cell as described in WO 2019/051609, developed by the Berlinguette group at University of British Columbia (page
21, lines 19-21)).
Regarding claim 43, WO ‘447 does not explicitly teach wherein in (d), the total concentration of said one or more carbonate or bicarbonate ions in said electrolyte solution is less than 1.5 M.
WO ‘447 teaches that:
Upon conversion of the bicarbonate ions in the conversion unit, where the bicarbonate ions are converted into CO and H2, the bicarbonate/carbonate ratio is then reduced and, in some embodiments, the stream exiting the conversion unit can present a bicarbonate/carbonate ratio which can be close or substantially similar to the bicarbonate/carbonate ratio in the initial stream (16) which was
treated in the absorption unit. For example, if stream (16) contained bicarbonate/carbonate ions in a ratio of 1 and that after absorption of the CO2 in the absorption unit, the ratio in stream (20) is 8, one can expect, in some embodiments, to return to a ratio of 1, or close to 1, at the exit of the conversion unit once the bicarbonate ions have been converted into CO and H2 (page 14, lines 12-21).
When the absorption compound is sodium carbonate, the sodium carbonate solution can have a sodium concentration ranging from 0.5 to 2 mol/l. In some embodiments, the sodium carbonate absorption solution can have a sodium concentration ranging from 0.5 to 1.5 mol/l, or from 0.5 to 1 mol/l, or from 1 to 2 mol/l, or from 1 to 1.5 mol/l, or from 1.5 to 2 mol/l. The CO2 loading of the absorption solution entering the gas/liquid absorption unit can range from 0.5 to 0.75 mol C/mol Na+, or from 0.5 to 0.7 mol C/mol Na+, or from 0.6 to 0.7 mol C/mol Na+. Furthermore, the CO2 loading of the absorption solution leaving the gas/liquid absorption unit
can range from 0.75 to 1 mol C/mol Na+, or from 0.75 to 0.9 mol C/mol Na+, or from 0.75 to 0.8 mol C/mol Na+, or from 0.8 to 0.95 mol C/mol Na+ (page 18, lines 11-19).
When the absorption compound is potassium carbonate, the potassium carbonate solution can have a potassium concentration ranging from 1 to 6 mol/l. In some embodiments, the potassium carbonate absorption solution can have a potassium concentration ranging from 1 to 5 mol/l, or from 1 to 4 mol/l, or from 1 to 3 mol/l, or from 1 to 2 mol/l, or from 2 to 6 mol/l, or from 2 to 5 mol/l, or from 2 to 4 mol/l, or from 2 to 3 mol/l, or from 3 to 6 mol/l, or from 3 to 5 mol/l, or from 3 to 4 mol/l, or from 4 to 6 mol/l, or from 4 to 5 mol/l, or from 5 to 6 mol/l. The CO2 loading of the absorption solution entering the gas/liquid absorption unit can range from 0.5 to 0.75 mol C/mol K+, or from 0.5 to 0.7 mol C/mol K+, or from 0.6 to 0.7 mol C/mol K+. Furthermore, the CO2 loading of the absorption solution leaving the gas/liquid absorption unit can range from 0.75 to 1 mol C/mol K+, or from 0.75 to 0.9 mol C/mol K+, or from 0.75 to 0.8 mol C/mol K+, or from 0.8 to 0.95 mol C/mol K+ (page 18, lines 20-30).
WO ‘938 teaches that:
One aspect of the invention provides a carbon capture method comprising chemically reacting gaseous carbon dioxide to form bicarbonate and/or carbonate in an aqueous solution. The aqueous solution is supplied at a cathode of an electrochemical reactor comprising an anode and the cathode separated by a bipolar membrane. A potential difference is applied between the anode and the cathode to cause an electrochemical reaction yielding product gas comprising one or both of gas phase carbon dioxide and gas phase carbon monoxide. The product gas is subsequently separated from the aqueous solution (ρ [0009]).
The aqueous solution precipitates a carbonate and/or bicarbonate after contacting the gas in some embodiments. The concentration of carbonate and/or bicarbonate ions in the aqueous solution may, for example, be in the range of 0.5M to 3M (ρ [0015]).
The subject matter would have been obvious to one having ordinary skill in the art
before the effective filing date of the claimed invention because WO ‘447 teaches that upon conversion of the bicarbonate ions in the conversion unit,3 the stream exiting the conversion unit can present a bicarbonate/carbonate ratio which can be close or substantially similar to the bicarbonate/carbonate ratio in the initial stream which was treated in the absorption unit
on page 14, lines 12-17, where when the absorption compound is sodium carbonate, the sodium carbonate solution can have a sodium concentration ranging from 0.5 to 2 mol/l (page 18, lines 11-12) and when the absorption compound is potassium carbonate, the potassium carbonate solution can have a potassium concentration ranging from 1 to 6 mol/l (page 18, lines 20-21).
Thus, the total concentration of said one or more carbonate or bicarbonate ions in said electrolyte solution exiting the conversion unit would have included a total concentration ranging from 0.5 to 2 mol/l.
II. Claim(s) 20-22 and 34-36 stand rejected under 35 U.S.C. 103 as being unpatentable over
WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as
applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of WO 2019/160413
(‘413).
Regarding claim 20, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches
the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do not explicitly teach subsequent to (d), separating said one or more carbon products from said electrolyte solution.
WO ‘447 teaches that the conversion experiments were conducted using the
Berlinguette Flow Cell as described in WO 2019/051609, developed by the Berlinguette group at University of British Columbia (page 21, lines 19-21).
WO ‘609 teaches that the electrolyzer outlet was introduced into a condenser before being vented directly into the gas-sampling loop of the gas chromatograph (GC, Perkins Elmer; Clarus 580) [pages 22-23, [0111]].
WO ‘413 teaches that:
It is further preferred that the reduced carbon dioxide product or product mixture is gaseous (such as gaseous carbon monoxide, methane or ethylene). This gives the advantage in that separation of the product is easier as compared to the separation of liquid reduction products (page 17, lines 16-19).
The apparatus may further comprise a separation unit, such as a stripper unit, connected to the electrochemical cell (page 21, lines 23-24).
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 method taught by modified WO ‘447 with subsequent to (d), separating said one or more carbon products from said electrolyte solution. The person with ordinary skill in the art would have been motivated to make this
modification because connecting a separation unit to the electrochemical cell would have separated a product from the product mixture.
Regarding claim 21, WO ‘447 teaches directing at least a portion of said electrolyte
solution back to said contactor to capture additional CO2 (= then, the mixture of the
bicarbonate depleted stream (16) and separated carbonic anhydrase or analogue thereof (34) can be sent back to the gas/liquid absorption unit (10)) [page 17, lines 20-22].
Regarding claim 22, WO ‘609 teaches wherein said separating is performed in absence
of a distillation unit (= the electrolyzer outlet was introduced into a condenser before being vented directly into the gas-sampling loop of the gas chromatograph (GC, Perkins Elmer; Clarus 580)) [pages 22-23, [0111]].
WO ‘413 teaches wherein said separating is performed in absence of a distillation unit (= the apparatus may further comprise a separation unit, such as a stripper unit, connected to the electrochemical cell) [page 21, lines 23-24].
Regarding claim 34, WO ‘447 teaches wherein said portion of said electrolyte solution reenters said electrochemical stack prior to being directed back to said contactor (= hence, in a continuous process) [page 10, lines 21-24; and page 12, line 32].
Regarding claim 35, WO ‘447 teaches wherein a pH of said portion of said electrolyte
solution is increased upon said reentry into said electrochemical stack (= a pH of the aqueous adsorption solution can range from 8.5 to 10.5) [page 5, lines 15-17].
Regarding claim 36, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do
not explicitly teach wherein a concentration of one or more hydroxide ions in said portion of said electrolyte solution is increased upon said reentry into said electrochemical stack.
The subject matter would have been obvious to one having ordinary skill in the art
before the effective filing date of the claimed invention because WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. Hence, similar processes can reasonably be expected to yield products which inherently have the same properties. In re Spada 911 F.2d 705, 15 USPQ 2d 1655 (CAFC 1990);
In re DeBlauwe 736 F.2d 699, 222 USPQ 191 (CAFC 1984); In re Wiegand 182 F.2d 633, 86 USPQ 155 (CCPA 1950).
A process yielding an unobvious product may nonetheless be obvious where Applicant claims a process in terms of function, property or characteristic and the process of the prior art is the same or similar as that of the claim but the function is not explicitly disclosed by the
reference. See MPEP § 2116.01.
III. Claim(s) 30 and 39 stand rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as
applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of Torres et al. (US Patent Application Publication No. 2019/0240621 A1).
Regarding claim 30, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches
the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do
not explicitly teach wherein prior to entering said contactor, said electrolyte solution has a pH from about 5 to about 7.
Torres teaches that:
FIG. 2 shows one embodiment of a system for CO2 capture and hydrogen generation 40. FIG. 2 includes a carbon capture device 42, which may be a unit operation open to an
atmosphere, where the atmosphere is whatever gaseous environment in which the unit operates. This may be open air, a mixture of gasses, the exhaust conduit of a combustion process, etc. The carbon capture unit captures the CO2 from the atmosphere in an alkaline capture solution, as discussed above. The alkaline capture solution 44, in one embodiment having a pH of 10.6, then flows to a series of electrolyzers, starting with an initial electrolyzer 46. Each electrolyzer in the series raises the acidity of the solution until it reaches a point at which the captured CO2 bubbles out of the capture solution after passing through a final electrolyzer in the series 48 and entering a flash tank 50. As mentioned before, it is possible that the initial electrolyzer, the final electrolyzer, and the return electrolyzer are the same electrolyzer, meaning that the series of electrolyzers is a series of 1 (ρ [0030]).
The subject matter as a whole would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention because the carbon capture unit captures the CO2 from the atmosphere in an alkaline capture solution where electrolyzing the alkaline capture solution would have raised the acidity of the solution until it reaches a point at which the captured CO2 bubbles out of the capture solution as taught by Torres in [0030].
Regarding claim 39, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do not explicitly teach wherein subsequent to (b), said electrolyte solution has a pH of at least 8.
WO ‘447 teaches that a pH of the aqueous adsorption solution can range from 8.5 to 10.5 (page 5, lines 16-17).
The subject matter would have been obvious to one having ordinary skill in the art
before the effective filing date of the claimed invention because since the CO2 is captured from the atmosphere into an aqueous adsorption solution having a pH ranging from 8.5 to 10.5, one having ordinary skill in the art would have expected that the electrolyte solution subsequent to
the contacting would have had a similar pH to the aqueous adsorption solution that the CO2 was captured in.
IV. Claim(s) 31 stands rejected under 35 U.S.C. 103 as being unpatentable WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of WO 2019/160413 (‘413) as applied to claims 20-22 and 34-36 above, and further in view of Eastman et al. (US Patent Application Publication No. 2008/0283411 A1).
Regarding claim 31, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above, and further in view of WO ‘413 as applied above. The references do not explicitly teach directing said one or more carbon products to a condenser.
WO ‘447 teaches that the conversion experiments were conducted using the Berlinguette Flow Cell as described in WO 2019/051609, developed by the Berlinguette group at University of British Columbia (page 21, lines 19-21).
WO ‘609 teaches that the electrolyzer outlet was introduced into a condenser before being
vented directly into the gas-sampling loop of the gas chromatograph (GC, Perkins Elmer; Clarus 580) [pages 22-23, [0111]].
Eastman teaches that:
The hydrocarbons produced at the cathode of the electro-hydrocarbon device may be
emitted from the device either as liquids or, because it may be necessary to operate the device
at temperatures high enough to vaporize the alcohol, as gases. If the hydrocarbons produced at
the cathode of the electro-hydrocarbon device are emitted as gases, then the hydrocarbons subsequently can be condensed to a liquid as is commonly known in the art (page 11, [0251]).
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 method taught by modified WO ‘447 by directing said one or more carbon products to a condenser. The person with ordinary skill in the art would have been motivated to make this modification because the products at the cathode of an electrolytic device emitted as gases would have been liquified by condensing as taught by Eastman in [0251].
V. Claim(s) 32 stands rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of Karnwiboon et al. (“Solvent Extraction of Degradation Products in Amine Absorption Solution for CO2 Capture in Flue Gases from Coal Combustion: Effect of Amines,” Energy Procedia (2017 Jul 1), Vol. 114, pp.
1980-1985).
Regarding claim 32, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches
the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. . The references do not explicitly teach wherein said electrolyte solution further comprises one or more formate ions.
Karnwiboon teaches that:
In the presence of CO2 loading, the extraction efficiency of formate decreased due to
competitive reactions between carbamate (R1R2NCOO-), bicarbonate (HCO3-) and carbonate (CO32-) with the extractant (page 1980, abstract).
The subject matter would have been obvious to one having ordinary skill in the art
before the effective filing date of the claimed invention because formate is a competitive reaction between carbamate (R1R2NCOO-), bicarbonate (HCO3-) and carbonate (CO32-) with the extractant as taught by Karnwiboon on page 1980, abstract.
VI. Claim(s) 33 stands rejected under 35 U.S.C. 103 as being unpatentable WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of WO 2018/160888 (‘888).
Regarding claim 33, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do not explicitly teach wherein said contactor comprises a direct air capture unit.
Olah teaches that although the CO2 content in the atmosphere is low (only 0.037%), the atmosphere offers an abundant and unlimited supply because CO2 is recycled. For using
atmospheric carbon dioxide efficiently, CO2 absorption facilities are needed (page 8, [0076]).
WO ‘888 teaches that:
Capturing CO2 directly from the atmosphere, referred to as direct air capture (DAC), is one of several means of mitigating anthropogenic greenhouse gas emissions and has attractive economic perspectives as a non-fossil, location-independent CO2 source for the commodity market and for the production of synthetic fuels. The specific advantages of CO2 capture from
the atmosphere include: (i) DAC can address the emissions of distributed sources (e.g. cars, planes), which account for a large portion of the worldwide greenhouse gas emissions and can currently not be captured at the site of emission in an economically feasible way; (ii) DAC can address emissions from the past and can therefore create truly negative emissions; and (iii) DAC systems do not need to be attached to the source of emission but are rather location
independent and can for example be located at the site of further CO2 processing (page 3, lines 6-18).
Contact between the capture liquid and the DAC generated CO2-containing gas occurs under conditions such that a substantial portion of the CO2 present in the DAC generated CO2-containing gas goes into solution, e.g., to produce bicarbonate ions. By substantial portion is meant 10 % or more, such as 50% or more, including 80% or more (page 11, lines 1-4).
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 contactor taught by modified WO ‘447 with wherein said contactor comprises a direct air capture unit. The person with ordinary skill in the art would have been motivated to make this modification because direct air capture (DAC) would have captured CO2 directly from the atmosphere where the CO2 present in the DAC generated CO2-containing gas goes into solution, e.g., to produce bicarbonate ions as taught by WO ‘888 on page 3, lines 6-18, and page 11, lines 1-4.
VII. Claim(s) 42 stands rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/010447 (‘447) in view of WO 2019/051609 (‘609), Olah et al. (US Patent Application Publication No. 2006/0235091 A1), WO 2005/108297 (‘297) and WO 2019/204938 (‘938) as applied to claims 19, 25, 27, 37, 40-41 and 43 above, and further in view of Jiang et al. (“Ion Exchange Membranes for Electrodialysis: A Comprehensive Review of Recent Advances,“ Journal of Membrane and Separation Technology (2014 Dec 3), Vol. 3, No. 4, pp. 185-205).
Regarding claim 42, WO ‘447 in view of WO ‘609, Olah, WO ‘297 and WO ‘938 teaches
the method of at least claims 19, 25, 27, 37, 40-41 and 43 as applied above. The references do not explicitly teach wherein said bipolar membrane has a thickness of no more than about 200 µm.
WO ‘447 teaches that in some embodiments, the electrolytic cell can be a bipolar membrane-based electrolytic cell (page 20, lines 9-10).
Jiang teaches the main properties of some commercially available ion exchange
membranes where FuMA-Tech GmbH’s BPM FBM membrane has thicknesses in the range of
180-200 µm (page 187, Table 1).
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 bipolar membrane taught by modified WO ‘447 with wherein said bipolar membrane has a thickness of no more than about 200 µm. The person with ordinary skill in the art would have been motivated to make this modification because commercially available bipolar membranes such as FuMA-Tech GmbH’s BPM FBM membrane would have had thicknesses in the range of 180-200 µm as taught by Jiang on page 187, Table 1.
Response to Arguments
Applicant's arguments filed April 28, 2026 have been fully considered but they are not
persuasive. The standing prior art rejections have been maintained for the following reasons:
• Applicant states that accordingly, the “total concentration” of carbonate and bicarbonate ions in ‘447 is 2.16 M, well over the claimed range of “no more than 2.0 M.”
• Applicant states that since ‘447 describes point source capture from a much more
concentrated CO2 source, the resulting solution has a higher total concentration of bicarbonate or carbonate ions.
In response, a reference is not limited to the working examples. See In re Fracalossi, 215
USPQ 569 (CCPA 1982).
All disclosures of the prior art, including non-preferred embodiment, must be considered, In re Lamberti and Konort, 192 USPQ 278 (CCPA 1967). All disclosure in the reference patent, not just specific examples, must be evaluated for what it fairly teaches those of ordinary skill in the art, In re Snow and Steinhards, 176 USPQ, 328, 329 (CCPA 1973). Non-preferred embodiments can be indicative of obviousness, see Merck & Co. v. Biocraft Laboratories Inc. 10 USPQ2d 1843 (Fed. Cir. 1989); In re Lamberti, 192 USPQ 278 (CCPA 1976); In re Kohler, 177 USPQ 399.
WO ‘447 teaches that:
Upon conversion of the bicarbonate ions in the conversion unit, where the bicarbonate ions are converted into CO and H2, the bicarbonate/carbonate ratio is then reduced and, in some embodiments, the stream exiting the conversion unit can present a bicarbonate/carbonate ratio which can be close or substantially similar to the bicarbonate/carbonate ratio in the initial stream (16) which was
treated in the absorption unit. For example, if stream (16) contained bicarbonate/carbonate ions in a ratio of 1 and that after absorption of the CO2 in the absorption unit, the ratio in stream (20) is 8, one can expect, in some embodiments, to return to a ratio of 1, or close to 1, at the exit of the conversion unit once the bicarbonate ions have been converted into CO and H2 (page 14, lines 12-21).
The total concentration of said one or more carbonate or bicarbonate ions in said electrolyte solution exiting the conversion unit would have included a total concentration ranging from 0.5 to 2 mol/l (WO ‘447: pages 18, lines 11-12 and 20-21).
• Applicant states that ‘609 does not remedy the above-mentioned deficiencies of ‘447.
In response, although WO ‘609 teaches providing a gas containing carbon dioxide at the
cathode of an electrolytic cell, WO ‘447 teaches that the electrolytic cell disclosed by WO ‘609 is
suitable to use as the conversion unit (page 20, lines 9-13) for the method.
• Applicant states that Olah does not remedy the above-mentioned deficiencies of ‘447.
In response, WO ‘447 teaches that the CO2-containing gas is an industrial exhaust gas on page 11, line 26-27, where the atmosphere is an alternative to industrial exhaust streams as a carbon dioxide source as taught by Olah in [0054] and where the capture and use of existing atmospheric CO2 would have allowed chemical recycling of CO2 as a renewable and unlimited source of carbon as taught by Olah in [0076].
Furthermore, the substitution of art recognized equivalents as shown by Olah in [0054] is within the level of ordinary skill in the art. In addition, the substitution of one carbon dioxide source for another is likely to be obvious when it does nothing more than yield predictable results.
• Applicant states that in the ‘391 provisional, the bicarbonate/carbonate solutions were not obtained by capturing CO2 from an atmospheric air stream but rather starting with bicarbonate/carbonate salts (KHCO3 and K2CO3). See ‘391 provisional at page 17, second paragraph. Accordingly, the subject matter of ‘938 that the Office references in the Office Action is not entitled to priority to the filing date of the ‘391 provisional (April 25, 2018).
In response, the rejection is not overcome by pointing out that one reference does not
contain a particular limitation when reliance for that teaching is on another reference. In re Lyons 150 USPQ 741 (CCPA 1966). Moreover, it is well settled that one cannot show nonobviousness by attacking the references individually where, as here, the rejection is based on a combination of references. In re Keller 208 USPQ 871 (CCPA 1981); In re Young 159 USPQ 725 (CCPA 1968).
WO ‘938 is relied upon for the teaching of the aqueous solution supplied at a cathode of an electrochemical reactor (ρ [0009]) comprising a concentration of carbonate and/or bicarbonate ions in the aqueous solution in the range of 0.5M to 3M (ρ [0015]).
In the ‘391 provisional, the reference teaches using electrolyte solutions having 0.5 to 3.0 M KHCO3 (page 14, Table 2). Thus, 1 mol/l, for example, would have been a suitable concentration for bicarbonate in an electrolyte solution supplied to the electrochemical cell of WO ‘447 for producing CO and H2.4
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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/EDNA WONG/Primary Examiner, Art Unit 1795
1 See also WO ‘297 for teaching the capturing of CO2 directly from the atmosphere (pages 27-28, Example 1).
2 The conversion unit (12) comprises an electrolytic cell (page 12, line 20).
3 The conversion unit (12) comprises an electrolytic cell (page 12, line 20).
4 WO ‘447 teaches that when the absorption compound is sodium carbonate, the sodium carbonate solution can have a sodium concentration ranging from 0.5 to 2 mol/l (pages 18, lines 11-12) and when the absorption compound is potassium carbonate, the potassium carbonate solution can have a potassium concentration ranging from 1 to 6 mol/l (page 18, lines 20-21).
Prosecution Insights