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 .
This is in response to the Amendment dated June 4, 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
Election/Restrictions
This application contains claims 8-15 (species) drawn to an invention nonelected without traverse in the reply filed on November 3, 2025 is acknowledged.
The requirement is still deemed proper and is therefore made FINAL.
Accordingly, claims 8-15 are withdrawn from consideration as being directed to a non-elected invention.
Specification
The disclosure has been objected to because of minor informalities.
The objection of the disclosure has been withdrawn in view of Applicant’s amendment.
Claim Objections
Claim 7 has been objected to because of minor informalities.
The objection of claim 7 has been withdrawn in view of Applicant’s amendment.
Claim Rejections - 35 USC § 103
I. Claim(s) 2, 4 and 6 have been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1).
The rejection of claims 2, 4 and 6 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. has been withdrawn in view of Applicant’s amendment.
II. Claim(s) 5 has been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24).
The rejection of claim 5 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in view of Wang et
al. has been withdrawn in view of Applicant’s amendment.
III. Claim(s) 7 has been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium
Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp.
240-249).
The rejection of claim 7 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. has been withdrawn in view of Applicant’s amendment.
IV. Claim(s) 16 has been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp.
240-249) as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444).
The rejection of claim 16 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) has been withdrawn in view of Applicant’s amendment.
V. Claim(s) 17, 19 and 22 have been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249) as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claim 16 above, and further in view of Paleologou et al. (“Enhancement of the Current Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171).
The rejection of claims 17, 19 and under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in
view of Cheng et al. as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claim 16 above, and further in view of Paleologou et al. has been withdrawn in view of Applicant’s amendment.
VI. Claim(s) 18 has been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium
Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249) as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claims 16 above, and further in view of Paleologou et al. (“Enhancement of the Current Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171) as applied to claims 17, 19 and 22 above, and further in view of Eastman et al. (US Patent Application Publication No. 2008/0283411 A1).
The rejection of claim 18 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claims 16 above, and further in view of Paleologou et al. as applied to claims
17, 19 and 22 above, and further in view of Eastman et al. has been withdrawn in view of Applicant’s amendment.
VII. Claim(s) 20 and 21 have been rejected under 35 U.S.C. 103 as being unpatentable over Skarlos (US Patent No. 3,720,591) in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications (2015 Dec 1), Vol. 61, pp. 97–101) and Bush et al. (US Patent Application Publication No. 2023/0126394 A1) as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1),
Vol. 17, pp. 240-249) as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claims 16 above, and further in view of Paleologou et al. (“Enhancement of the Current Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171) as applied to claims 17, 19 and 22 above, and further in view of Salama et al. (US Patent Application Publication Application No. 2009/0120863 A1).
The rejection of claims 20 and 21 under 35 U.S.C. 103 as being unpatentable over Skarlos in view of Pletcher and Bush et al. as applied to claims 2, 4 and 6 above, and further in view of Cheng et al. as applied to claim 7 above, and further in view of CA 2732002 (‘002) and SU 937444 (‘444) as applied to claims 16 above, and further in view of Paleologou et al. as
applied to claims 17, 19 and 22 above, and further in view of Salama et al. has been withdrawn in view of Applicant’s amendment.
Continued Response
Drawings
The drawings were received on June 4, 2026. These drawings are acceptable.
Claim Objections
Claims 2, 7, 16 and 20 are objected to because of the following informalities:
Claim 2
line 3, please insert -- (CO2) -- after the word “dioxide”. See claim 20, line 3.
Claim 7
line 2, please amend the word -- a -- (second occurrence) to the word -- the --.
This is an instance where the article should be changed to ensure proper antecedent basis for the claim terminology.
line 3, please amend the word -- a -- to the word -- the --.
This is an instance where the article should be changed to ensure proper antecedent basis for the claim terminology.
Claim 16
line 2, please insert the word -- the -- before the word “sulfuric”.
This is an instance where the article should be changed to ensure proper antecedent
basis for the claim terminology.
line 2, please insert the word -- the -- before the word “sodium”.
This is an instance where the article should be changed to ensure proper antecedent
basis for the claim terminology.
Claim 20
line 2, please amend the word “conversion” to the word -- reaction --.
This is an instance where the article should be changed to ensure proper antecedent
basis for the claim terminology.
line 3, please insert the word -- the -- before the word “oxalate”.
This is an instance where the article should be changed to ensure proper antecedent
basis for the claim terminology.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
Claims 16-22 are 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 16
line 2, “the sodium sulfate solution” 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.
Please amend “the sodium sulfate solution” to -- the resultant salt solution --.
Claim 18
line 1, “the cathode” 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 anode” 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 19
line 1, “the electrolysis cell” 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 20
line 1, “the cathode” lacks antecedent basis. See also claim 20, line 3.
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.
See also claim 20, line 3.
Claim 21
line 1, “the cathode” 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.
See also claim 21, lines 2-3.
line 3, “the surface area” 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 22
line 1, “the cathode” 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
I. Claim(s) 2 and 4-5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Albertson (US Patent No. 3,471, 384) in view of Bush et al. (US Patent Application Publication No. 2023/0126394 A1), Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24), Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249), Skarlos (US Patent No. 3,720,591) and CA 2732002 (‘002).
Regarding claim 2, Albertson teaches a method (= method) [col. 1, line 13], the
method comprising:
• providing a feedstock of purified carbon dioxide (= the carbon dioxide is vented from the acidifying chamber 22 as shown) [col. 3, lines 28-29], the feedstock of purified carbon dioxide derived from a captured carbon dioxide (= absorb carbon dioxide from the air using an absorption column) [col. 2, lines 18-19],
۰ wherein the captured carbon dioxide is captured using a scrubbing absorption column having a scrubbing solution comprising sodium hydroxide (NaOH) [= the sodium hydroxide formed and collected at the cathode, along with the hydrogen, is used to absorb carbon dioxide from the air using an absorption column) [col. 2, lines 16-19], and
۰ wherein the captured carbon dioxide is in the form of a metal bicarbonate solution comprising sodium bicarbonate (= an air scrubber to pick up carbon dioxide carried by the air in the enclosed atmosphere, thereby to form sodium bicarbonate)
[col. 4, lines 67-69], and
۰ wherein the metal bicarbonate solution is reacted with an acid reagent comprising sulfuric acid to produce the feedstock of purified carbon dioxide (=
neutralizing said sodium bicarbonate solution by adding sulfuric acid formed at the anode, to thereby release carbon dioxide from the solution) [col. 4, lines 70-72] and a
resultant salt solution comprising sodium sulfate (Na2SO4) [= adding sufficient sulfuric
acid from the anode to the sodium bicarbonate solution to form sodium sulfate salt solution] (col. 4, line 75 to col. 5, line 2);
• subjecting the resultant salt solution to electrolysis (= the sodium sulfate salt solution formed in this step is re-electrolyzed) [col. 2, lines 22-23] with membrane separation to
regenerate sulfuric acid and sodium hydroxide from the resultant salt solution (= a solution of sodium sulfate which is electrolyzed within the diaphragmed cell to form an acid and a base (H2SO4 and NaOH respectively)) [col. 2, lines 7-9];
• reusing the regenerated sodium hydroxide as at least a portion of the scrubbing
solution in the scrubbing absorption column to capture additional carbon dioxide (= the sodium hydroxide formed and collected at the cathode, along with the hydrogen, is used to absorb carbon dioxide from the air using an absorption column) [col. 2, lines 16-19]; and
• reusing the regenerated sulfuric acid as at least a portion of the acid reagent to produce additional feedstock of purified carbon dioxide and the resultant salt solution
comprising Na2SO4 (= the absorbed carbon dioxide is released from the basic solution by neutralizing the caustic-carbonate solution with sulfuric acid formed at the anode by
electrolysis) [col. 2, lines 19-22].
Albertson does not explicitly teach the following:
a. For the production of oxalic acid.
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 this limitation, recited in the preamble of claim 2, is the intended use of the method.
MPEP § 2111.02(II) states that “where a patentee defines a structurally complete invention in the claim body and uses the preamble only to state a purpose or intended use for the invention, the preamble is not a claim limitation”. See also Rowe v. Dror, 112 F.3d 473, 478, 42 USPQ2d 1550, 1553 (Fed. Cir. 1997).
b. Where the captured carbon dioxide is from an emissions source.
Albertson teaches an air + CO2 feed (= drawing:
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193
228
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Greyscale
Bush teaches capturing carbon dioxide from dilute sources such as ambient air or from flue gas streams (page 1, [0002]; and Fig. 4:
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118
235
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).
Wang teaches that to mitigate CO2 emissions, the research and development efforts in
CO2 capture and separation both from the stationary sources with high CO2 concentrations (e.g., coal-fired power plant flue gas) and directly from the atmosphere have grown significantly (page 1, 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 carbon dioxide taught by Albertson with where the captured carbon dioxide is from an emissions source. The person with ordinary
skill in the art would have been motivated to make this modification because Albertson teaches
an air + CO2 feed in the drawing where a coal-fired power plant flue gas would have been a suitable form of CO2 for capture as taught by Bush in [0002] and Fig. 4, and Wang on page 1, abstract, which would have provided a reason for one of ordinary skill in the art to have selected it. See Merck & Co. V. Biocraft Labs., Inc., 874 F.2d 804, 807 (Fed. Cir. 1989) (“That the ‘813 patent discloses a multitude of effective combinations does not render any particular formulation less obvious.”). In addition, the substitution of one CO2 feed or source for another is likely to be obvious when it does nothing more than yield predictable results.
c. Wherein the scrubbing solution is a slurry scrubbing solution.
Cheng teaches that a bubble column reactor was tested and evaluated for carbon
dioxide removal from flue gases by using magnesium hydroxide slurry. The study showed that a
high CO2 removal efficiency could be achieved (page 240, abstract).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the scrubbing solution described by Albertson with wherein the scrubbing solution is a slurry scrubbing solution. The person with ordinary skill in the art would have been motivated to make this modification because a high CO2 removal efficiency from flue gases would have been achieved using a bubble column reactor containing a magnesium hydroxide slurry as taught by Cheng on page 240, abstract.
d. Electrochemically reducing the feedstock of purified carbon dioxide produced by reaction of the metal bicarbonate solution with the acid reagent to an oxalate salt.
e. Converting the oxalate salt to oxalic acid.
Albertson teaches that the carbon dioxide formed is vented from the enclosed atmosphere (col. 2, lines 3-5).
Skarlos teaches that:
Oxalic acid and oxalate salts are produced commercially to fill a great variety of end uses. For example, they are used in laundries as a rust and ink remover, as the chief constituent in automobile radiator scale removers, as an electrolyte in the anodic oxidation of aluminum, as a bleaching agent for such materials as straw, cork, rosin and wood, as reagents in chemical analysis and in the manufacture of miscellaneous chemical derivatives (col. 1, lines 10-19).
The improvement comprises:
a. introducing carbon dioxide into the cathode compartment of the electrolytic cell to contact therein a catholyte comprising a non-aqueous liquid solvent and a C1 -C5 alkyl quaternary ammonium salt soluble in said solvent,
b. applying a voltage to the electrodes of said cell to pass a direct current through said cell thereby forming an oxalate salt, and
c. recovering the oxalate salt from the catholyte.
The oxalate salt may be converted to oxalic acid by contacting the salt with an acid to
produce a salt of the acid and oxalic acid (col. 2, lines 7-20).
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 Albertson by electrochemically reducing the feedstock of purified carbon dioxide produced by reaction of the metal bicarbonate solution with the acid reagent to an oxalate salt and converting the oxalate salt to oxalic acid. The person with ordinary skill in the art would have been motivated to make this modification because Albertson teaches venting the carbon dioxide. Since it is well within the skill of the art to collect the vented CO2 of Albertson and to recycle it in order to minimize the amount of waste produced for ecological and economic reasons, see Ex parte Fuller 172 USPQ 317, one having ordinary skill in the art would have electrochemically reducing the carbon dioxide produced by Albertson to an oxalate salt and oxalic acid because oxalic acid and oxalate salts are produced commercially to fill a great variety of end uses. For example, they are used in laundries as a rust and ink remover, as the chief constituent in automobile radiator scale removers, as an electrolyte in the anodic oxidation of aluminum, as a bleaching agent for such materials as straw, cork, rosin and wood, as reagents in chemical analysis and in the manufacture of miscellaneous chemical derivatives as taught by Skarlos in col. 1, lines 10-19.
f. Wherein the membrane is a bipolar membrane.
Albertson teaches the aqueous salt solution used to generate oxygen may be, for example, a solution of sodium sulfate which is electrolyzed within the diaphragmed cell to form an acid and a base (H2SO4 and NaOH respectively) [col. 2, lines 6-9].
CA ‘002 teaches that:
In other embodiments, step 10 of FIGS. 1A-1B and 3A-3B may include an electrodialysis process such as electro-electrodialysis, salt splitting or bipolar membrane electrodialysis. These processes uses an applied voltage to drive opposite-charged ions in a salt solution in opposite directions through membranes engineered for high permeability of ions of a particular charge state. Charge-compensating ions are generated by the electrolysis of water, resulting in acid and base exit streams. A suitable process is described in “Electrodialysis Process With Bipolar Membranes (EDBM) in Environmental Protection - A Review”, by Tongwen Xu, Resources, Conservation and Recycling (2002), which is incorporated herein by reference (page 5, line 30 to page 6, line 5).
In some embodiments, as indicated by FIG. 3A, the process may involve co-production of sulfuric acid and sodium hydroxide. For example, the sulfuric acid may be produced from a reaction between metal sulfate salt (e.g., sodium sulfate) and water. A bipolar membrane electrodialysis process may be used. A representative reaction is:
Na₂SO₄ + 2H2O → 2NaOH + H2SO4
It should be understood that in any of the above reactions, sodium may be replaced with another suitable cation such as potassium (page 6, lines 6-12).
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 diaphragm taught by Albertson with wherein the diaphragm is a bipolar membrane. The person with ordinary skill in the art would
have been motivated to make this modification because using a bipolar membrane would have
involved co-production of sulfuric acid and sodium hydroxide as taught by CA ‘002 on page 5, lines 30-32, and page 6, lines 6-12.
Regarding claim 4, modified Albertson teaches wherein the feedstock of purified carbon dioxide comprises industrial grade CO2 having a purity of at least 99.5%, medical grade CO2 having a purity of at least 99.5%, bone dry grade CO2 having a purity of at least 99.8%, food grade CO2 having a purity of at least 99.9%, beverage grade CO2 having a purity of at least
99.9%, anaerobic grade CO2 having a purity of at least 99.95%, or research grade CO2 having a
purity of at least 99.999% (= CO2↑) [col. 2, line 39].
Regarding claim 5, Wang teaches wherein the emissions source is a flue gas resulting
from combustion of a fossil fuel, wood, or a renewable power source (= coal-fired power plant flue gas) [page 1, abstract].
II. Claim(s) 6 and 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Albertson (US Patent No. 3, 471, 384) in view of Bush et al. (US Patent Application Publication No. 2023/0126394 A1), Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24), Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249), Skarlos (US Patent No. 3,720,591) and CA 2732002 (‘002) as applied to claims 2 and 4-5 above, and further in view of Pletcher (“The Cathodic Reduction of Carbon Dioxide -What Can It Realistically Achieve? A Mini Review,” Electrochemistry Communications
(2015 Dec 1), Vol. 61, pp. 97–101).
Regarding claim 6, Albertson, Bush, Wang, Cheng, Skarlos and CA ‘002 teach the method of at least claims 2 and 4-5 as applied above. The references do not explicitly teach wherein the captured CO2 is captured from a flue gas and has undergone further processing to provide a purity of at least 99.5%.
Pletcher teaches that:
In addition, there would need to be units (a) to extract pure CO2 (or at least a concentrated CO2 stream) from the atmosphere as feed to the electrolysis cells and (b) to
isolate the product in marketable form (if a market on an appropriate scale exists; see below) or convert all the cell products it into a safe form prior to discharge into the environment (page 97, right column, lines 6-8)).
The economics of a process such as that in Fig. 1 is apparently improved if (a) the CO2 is available in a more concentrated stream, e.g., flue gas (page 98, right column, lines 1-3).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the captured CO2 described by modified Albertson with wherein the captured CO2 is captured from a flue gas and has undergone further processing to provide a purity of at least 99.5%. The person with ordinary skill in the art would
have been motivated to make this modification because using units to extract pure CO2 as a feed to the electrolysis cells and to isolate the product in marketable form would have produced products in a safe form.
Furthermore, the repetition of steps to provide the same results is well within the skill of one having ordinary skill in the art. The concept of duplication is not patentable. St. Regis
Paper Co. v. Bemis Co. Inc., 193 USPQ 8, 11 (7th Cir. 1977). While this decision relates to the
duplication of parts, there is no reason why such duplication cannot be extended to a process
step.
Regarding claim 7, Cheng teaches wherein the captured CO2 has been captured from the flue gas using a chemical absorption capture of CO2 using a scrubbing absorption column having a slurry scrubbing solution that is capable of capturing CO2 from the flue gas (= a bubble
column reactor was tested and evaluated for carbon dioxide removal from flue gases by using magnesium hydroxide slurry) [page 240, abstract].
III. Claim(s) 16-17 and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Albertson (US Patent No. 3, 471, 384) in view of Bush et al. (US Patent Application Publication No. 2023/0126394 A1), Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24), Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249), Skarlos (US Patent No. 3,720,591) and CA 2732002 (‘002) as applied to claims 2 and 4-5 above, and further in view of Paleologou et al. (“Enhancement of the Current Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171).
Regarding claim 16, Albertson, Bush, Wang, Cheng, Skarlos and CA ‘002 teach the
method of at least claims 2 and 4-5 as applied above. CA ‘002 teaches wherein the electrodialysis with bipolar membrane separation separates the sodium sulfate solution into sulfuric acid and sodium hydroxide using at least one bipolar membrane (page 6, lines 6-12). The references do not teach and at least one cation exchange membrane.
Paleologou teaches a two-compartment bipolar membrane electrodialysis unit cell for generating a mixture of acid and salt (sulphuric acid and sodium sulphate) and base (sodium
hydroxide) from salt (sodium sulphate) [page 161, Fig. 1:
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].
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the electrodialysis with bipolar membrane separation described by modified Albertson with at least one cation exchange membrane. The person with ordinary skill in the art would have been motivated to make this modification because using a two-compartment bipolar membrane electrodialysis unit cell comprising a cation selective membrane would have been suitable for generating a mixture of acid and salt (sulphuric acid and sodium sulphate) and base (sodium hydroxide) from salt (sodium sulfate) as taught by Paleologou on page 161, Fig. 1.
Regarding claim 17, modified Albertson teaches wherein the regenerated sodium hydroxide is reused as at least a portion of the slurry scrubbing solution within the scrubbing absorption column (= the sodium hydroxide formed and collected at the cathode, along with the hydrogen, is used to absorb carbon dioxide from the air using an absorption column) [col. 2,
lines 16-19] and the regenerated sulfuric acid is reused as at least a portion of the acid reagent reacted with the metal bicarbonate solution (= the absorbed carbon dioxide is released from the basic solution by neutralizing the caustic-carbonate solution with sulfuric acid formed at the anode by electrolysis) [col. 2, lines 19-22] in a continuous closed-loop process (= the cycle is repeated (col. 2, line 23); and drawing).
Regarding claim 19, Albertson, Bush, Wang, Cheng, Skarlos, CA ‘002 and Paleologou teach the method of at least claims 2, 4-5 and 16-17 as applied above. The references do not explicitly teach wherein the electrolysis cell is devoid of a membrane between a catholyte region and an anolyte region.
Skarlos teaches that:
The design of the electrolytic cell may be widely varied. For example, each half cell may be separately constructed and joined together with the porous membrane located at the junction. In one embodiment the cell may comprise a single compartment divided by a wall, a portion or all of which may constitute the porous membrane. In another design the half-cell compartments may comprise concentrically positioned chambers with the porous membrane located in the wall of the inner chamber (col. 2, lines 55-65).
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 electrolysis cell taught by modified Albertson with wherein the electrolysis cell is devoid of a membrane between a catholyte region and an anolyte region. The person with ordinary skill in the art would have been motivated to make this modification because Skarlos teaches that the design of the electrolytic cell may be widely varied in col. 2, lines 55-56 and may comprise a single compartment divided by a wall, a portion or all of which may constitute the porous membrane in col. 2, lines 58-61,
which would have suggested that a membrane-less electrolytic cell would have been suitable to use where the substitution of art recognized equivalents as taught by Skarlos in col. 2, lines 55-65, is within the level of ordinary skill in the art. In addition, the substitution of one electrolytic cell for another is likely to be obvious when it does nothing more than yield predictable results.
IV. Claim(s) 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Albertson
(US Patent No. 3, 471, 384) in view of Bush et al. (US Patent Application Publication No.
2023/0126394 A1), Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24), Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1),
Vol. 17, pp. 240-249), Skarlos (US Patent No. 3,720,591) and CA 2732002 (‘002) as applied to
claims 2 and 4-5 above, and further in view of Paleologou et al. (“Enhancement of the Current Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171) as applied to claims 16-17 and 19 above, and further in view of Eastman et al. (US Patent Application Publication No. 2008/0283411 A1).
Regarding claim 18, Albertson, Bush, Wang, Cheng, Skarlos, CA ‘002 and Paleologou teach the method of at least claims 2, 4-5, 16-17 and 19 as applied above. The references do not explicitly teach wherein the cathode is wrapped at least partially around the anode in a
cylindrical configuration.
Skarlos teaches that in another design the half-cell compartments may comprise
concentrically positioned chambers with the porous membrane located in the wall of the inner
chamber (col. 2, lines 62-65).
Eastman teaches that:
FIG. 3 illustrates an exemplary physical configuration of an electro-hydrocarbon device. In FIG. 3, the electro-hydrocarbon device 300 is configured as a cylindrical unit. The cylinder wall has three layers--the exterior anode 310, the electrolyte 320, and the interior cathode 330. An electrical power source 340 is connected to the anode 310 and cathode 330 by external circuit wiring 350, cathodic electro-contact 351, and anodic electro-contact 352. A gaseous influent 360 comprising at least one of carbon monoxide and carbon dioxide flows through the interior of the
cylinder, thus contacting the cathode 330. Water 380 in the form of a vapor, steam, or liquid travels across the exterior of the cylinder, thus contacting the anode 310. The electrical power source 340 creates an electrical potential between the cathode 330 and the anode 310 that drives the electrolysis of water to create hydrogen ions and liberate oxygen in effluent 390. The
hydrogen ions travel from the anode 310 through the electrolyte 320 to reach the cathode 330,
where they react with carbon monoxide and/or carbon dioxide to create hydrocarbons in effluent 370 (page 10, [0245]).
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 cathode taught by modified Albertson with wherein the cathode is wrapped at least partially around the anode in a cylindrical configuration. The person with ordinary skill in the art would have been motivated to make this modification because a cylindrical unit where the cylinder wall has three layers - the exterior anode, the electrolyte (= membrane) [Eastman: page 8, [0180] et seq.], and the interior cathode is a device where carbon dioxide would have flowed into and been electrolyzed.
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.
V. Claim(s) 20-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Albertson (US Patent No. 3, 471, 384) in view of Bush et al. (US Patent Application Publication No. 2023/0126394 A1), Wang et al. (“Carbon Capture from Flue Gas and the Atmosphere: A Perspective,” Frontiers in Energy Research (2020 Dec 15), Vol. 8, pp. 1-24), Cheng et al. (“A Mass Transfer Model of Absorption of Carbon Dioxide in a Bubble Column Reactor by Using Magnesium Hydroxide Slurry,” International Journal of Greenhouse Gas Control (2013 Sep 1), Vol. 17, pp. 240-249), Skarlos (US Patent No. 3,720,591) and CA 2732002 (‘002) as applied to claims 2 and 4-5 above, and further in view of Paleologou et al. (“Enhancement of the Current
Efficiency for Sodium Hydroxide Production from Sodium Sulphate in a Two-Compartment Bipolar Membrane Electrodialysis System,” Separation and Purification Technology (1997 Jul 3), Vol. 11, No. 3, pp. 159-171) as applied to claims 16-17 and 19 above, and further in view of Salama et al. (US Patent Application Publication Application No. 2009/0120863 A1).
Regarding claim 20, Albertson, Bush, Wang, Cheng, Skarlos, CA ‘002 and Paleologou teach the method of at least claims 2, 4-5, 16-17 and 19 as applied above. The references do not explicitly teach wherein the cathode has a metal coating on a cathode surface that has an increased absorbing and conversion of the captured CO2 into oxalate salt compared to the cathode without the metal coating.
Skarlos teaches that:
The electrodes may be constructed from a variety of materials. The cathode material should have a high hydrogen overvoltage. Carbon, platinum, tin or zinc cathodes result in the
generation of a gas and are not preferred. Copper or lead amalgamated cathodes as well as mercury, lead, or stainless steel cathodes produce the desired results. Because of corrosion problems in the anode compartment, inert or corrosion resistant anodes are employed. Generally, carbon or graphite anodes are preferred (col. 2, lines 38-47).
Salama teaches that the production of ozone and other oxidative compounds is increased due to the roughness or dendrite plating of the anodes and cathodes, which increase the effective surface area of the electrodes (page 4, [0089]).
It would have been obvious to one having ordinary skill in the art before the effective
filing date of the claimed invention to have modified the cathode described by modified Albertson with wherein the cathode has a metal coating on a cathode surface that has an increased absorbing and conversion of the captured CO2 into oxalate salt compared to the
cathode without the metal coating. The person with ordinary skill in the art would have been motivated to make this modification because due to a roughness or dendrite plating of cathodes, which increases the effective surface area of the electrodes as taught by Salama in [0089], an increase in the reaction sites for the electrochemical reduction would have occurred where using copper and lead would have had a high hydrogen overvoltage as taught by Skarlos in col. 2, lines 38-47.
Regarding claim 21, Albertson, Bush, Wang, Cheng, Skarlos, CA ‘002 and Paleologou teach the method of at least claims 2, 4-5, 16-17 and 19 as applied above. The references do not explicitly teach wherein the cathode has a modified cathode surface comprising a metal coating that provides a rough surface area compared to the cathode without the metal coating, the
metal coating increasing the surface area of the cathode surface compared to the cathode
surface without the metal coating.
Skarlos teaches that:
The electrodes may be constructed from a variety of materials. The cathode material should have a high hydrogen overvoltage. Carbon, platinum, tin or zinc cathodes result in the
generation of a gas and are not preferred. Copper or lead amalgamated cathodes as well as mercury, lead, or stainless steel cathodes produce the desired results. Because of corrosion problems in the anode compartment, inert or corrosion resistant anodes are employed. Generally, carbon or graphite anodes are preferred (col. 2, lines 38-47).
Salama teaches that the production of ozone and other oxidative compounds is increased due to the roughness or dendrite plating of the anodes and cathodes, which increase the effective surface area of the electrodes (page 4, [0089]).
It would have been obvious to one having ordinary skill in the art before the effective
filing date of the claimed invention to have modified the cathode described by modified Albertson with wherein the cathode has a modified cathode surface comprising a metal coating that provides a rough surface area compared to the cathode without the metal coating, the metal coating increasing the surface area of the cathode surface compared to the cathode surface without the metal coating. The person with ordinary skill in the art would have been motivated to make this modification because due to a roughness or dendrite plating of cathodes, which increases the effective surface area of the electrodes as taught by Salama in [0089], an increase in the reaction sites for the electrochemical reduction would have occurred where using copper and lead would have had a high hydrogen overvoltage as taught by Skarlos in col. 2, lines 38-47.
Regarding claim 22, Albertson, Bush, Wang, Cheng, Skarlos, CA ‘002 and Paleologou teach the method of at least claims 2, 4-5, 16-17 and 19 as applied above. The references do
not explicitly teach wherein the cathode has a modified cathode surface comprising a metal coating comprising lead, zinc, steel, silver, iron or copper.
Skarlos teaches that:
The electrodes may be constructed from a variety of materials. The cathode material should have a high hydrogen overvoltage. Carbon, platinum, tin or zinc cathodes result in the
generation of a gas and are not preferred. Copper or lead amalgamated cathodes as well as mercury, lead, or stainless steel cathodes produce the desired results. Because of corrosion problems in the anode compartment, inert or corrosion resistant anodes are employed. Generally, carbon or graphite anodes are preferred (col. 2, lines 38-47).
Salama teaches that the production of ozone and other oxidative compounds is increased due to the roughness or dendrite plating of the anodes and cathodes, which increase the effective surface area of the electrodes (page 4, [0089]).
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 cathode taught by modified Albertson with wherein the cathode has a modified cathode surface comprising a metal coating comprising lead, zinc, steel, silver, iron or copper. The person with ordinary skill in the art would have been motivated to make this modification because due to a roughness or dendrite plating of cathodes, which increases the effective surface area of the electrodes as taught by Salama in [0089], an increase in the reaction sites for the electrochemical reduction would have occurred where using copper and lead would have had a high hydrogen overvoltage as taught by Skarlos in col. 2, lines 38-47.
Response to Arguments
Applicant’s arguments with respect to the prior art rejections of the claims have been
considered but are moot because the new grounds of rejection do not rely on the combination of references applied in the prior rejections of record for any teaching or matter specifically challenged in the argument.
Citations
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kosmoski et al. (US Patent Application Publication No. 2014/0010743) is cited to teach
methods to isolate salt reagents for electrochemical salt splitting and subsequent CO2 capture (page 5, [0080]; and Fig. 1).
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.
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
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