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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 28 August 2026 has been entered.
Response to Arguments
Applicant’s amendment to claim 12 in line 7 changing the instance of “an electrolyte” to “the electrolyte” requires reintroduction of the rejection under 35 U.S.C. 112(b) previously set forth in the Office action mailed 29 October 2025.
Applicant’s amendment to claim 12 adding limitations to the apparatus configured to reduce the O2 amount is clearly sufficient to overcome the obviousness rejection of claims over Ylasaari et al (as combined with Bulan et al and Gonzalez et al).
Applicant’s arguments filed 28 August 2026 are considered moot since new references have been added to address the deficiencies of the Bulan et al and Ylasaari et al presented in the arguments.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 12, 15, and 19-22 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 12 recites the limitation "the electrolyte" in line 7. There is insufficient antecedent basis for this limitation in the claim.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 12, 15, and 19-22 are rejected under 35 U.S.C. 103 as being unpatentable over Bulan et al (US 2013/0240370) in view of Gonzalez et al (“Plastic materials for the use of chlor-alkali industry”), Ylasaari et al (WO 93/24412) and Hoggan et al (“A Simple Production System for the Deoxygenation of Water”).
Bulan et al teach (see paragraphs [0032], [0034], [0071], and [0089]) an electrolysis apparatus comprising an electrolyzer having an electrolysis cell comprising an oxygen depolarized cathode suitable for an electrochemical process where oxygen gas is introduced into an electrolyte that is in contact with the cathode, an inlet (liquid inlet for sodium hydroxide solution), an outlet (liquid outlet for sodium hydroxide solution), and an apparatus (pump) configured to pressurize the electrolyte.
The electrolyte leaving the outlet of Bulan et al would have been understood as inherently containing dissolved oxygen gas due to the exposure of the electrolyte to oxygen gas at the cathode.
While Bulan et al fail to explicitly teach the use of plastic plumbing materials in contact with the electrolyte, the use of polypropylene and other plastics for plumbing including pipes and valves in the field of chloralkali electrolysis cells was well documented in the prior art, such as Gonzalez et al, due to the chemical resistance and low costs of the plastic materials. Thus, one of ordinary skill in the art at the time of filing would have been motivated to have used at least some plastic materials that contacted the electrolyte in the system of Bulan et al due to the known chemical resistance and low costs of the plastic materials.
Bulan fails to teach an apparatus for reducing the O2 amount of the electrolyte for introduction which is capable of achieving an O2 amount below 25 mg/L.
Ylasaari et al teach (see abstract, page 1, line 7 to page 2, line 11) that residual amounts of oxygen dissolved in circulating water, even at very low amounts of 10-20 μg O2 per kg of H2O, posed significant corrosion problems for plumbing systems.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have applied a deoxygenation step as taught by Ylasaari et al to the system of Bulan et al in order to have removed the residual dissolved oxygen from the circulating electrolyte of Bulan et al in order to reduce the corrosive power of the dissolved oxygen as taught by Ylasaari et al.
Ylasaari et al fail to teach that the deoxygenation apparatus included a stripping apparatus wherein the apparatus included a stripping space into which both the electrolyte and a stripping gas were introduced.
Hoggan et al teach (see Summary, Introduction and Plant Design sections on pages 246-248-253, figs. 2 and 3) a stripping apparatus for the deoxygenation of water comprising an inlet for the water that contains oxygen, a gas inlet for an inert stripping gas, a gas outlet for spent stripping gas (containing the oxygen removed from the water), and a liquid outlet for the deoxygenated water. The stripping apparatus of Hoggan et al was effective for removing even small quantities of dissolved oxygen gas from the water, achieving as little as 1 ppm (~1 mg/L) or 0.2 ppm (~0.2 mg/L).
Therefore, it would have been obvious to one of ordinary skill in the art to have combined the known deoxygenation technique of Hoggan et al to achieve the desired deoxygenation taught by Ylasaari et al because Ylasaari et al shows that many deoxygenation techniques were known and Hoggan et al teaches a simple apparatus for achieving very low concentrations of dissolve oxygen.
Regarding claim 15, it would have been obvious to one of ordinary skill in the art at the time of filing to have provided a storage vessel for any of the liquids utilized in the electrolysis apparatus, such as the electrolyte, for providing a buffer of the liquids for short duration maintenance and repairs. It would have been obvious to one of ordinary skill in the art at the time of filing to have placed the apparatus for reducing the O2 amount of Hoggan et al immediately downstream from the electrolysis cell (i.e. in fluid communication with the outlet) since the highest oxygen concentration in the electrolyte was at the outlet of the electrolysis cell and removal of the dissolved oxygen would have been expected to reduce corrosion in the remainder of the fluid system.
Regarding claim 19, Bulan et al teach using a pump as the apparatus for pressurizing.
Regarding claim 20, Hoggan et al teach (see first paragraph on page 253) that the vessel of the stripping apparatus was sized to ensure proper gas and liquid residence time. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have conducted routine experimentation to optimize the size of the vessel of Hoggan et al to ensure the proper residence time to deoxygenate the desired amount of aqueous solution.
Regarding claim 21, Hoggan et al teach (see figs. 2, 3, and 8) the stripping apparatus having a larger vertical size than any horizontal size, thus being in the shape of a column.
Regarding claim 22, Hoggan et al teach (see fig. 2 and lower half of page 247) providing countercurrent flow of water to be deoxygenated and stripping gas (nitrogen). The inlet for the water is arranged at the upper end of the stripping space and the outlet for the stripped electrolyte is arranged at a lower end of the stripping space. The outlet for the stripping gas is arranged at the upper end of the stripping space.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY D WILKINS III whose telephone number is (571)272-1251. The examiner can normally be reached M-F 9:30am -6:00pm.
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/HARRY D WILKINS III/Primary Examiner, Art Unit 1794
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