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 .
Claim Rejections - 35 U.S.C. § 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 of this title, 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 1, 3, & 5-8 are rejected under 35 U.S.C. § 103 as being unpatentable over Son et al., Electro-Forward Osmosis, 53 Environmental Science & Tech. 8352 (2019) [hereinafter Son].
The body of the claim is generally written with parentheses following the limitations indicating the prior art’s teachings and/or examiner notes.
1. A system for producing hydrogen and oxygen gases by water electrolysis (water split into hydrogen and oxygen gases; Son pp. 8352-54, 8357, figs. 1-2), the system comprising:
a vessel comprising a first and a second chamber (cathode and anode chambers; Son pp. 8352-54, figs. 1-2);
a membrane permeable to water ions separating the first chamber and the second chambers … and wherein the membrane is optionally permeable to water such that the first chamber is in fluid communication with the second chamber (reverse osmosis membrane letting water pass; Son p. 8353, figs. 1-2);
a cathode in contact with a catholyte in the first chamber, an anode in contact with an anolyte in the second chamber (cathode and anode in their respective chambers; Son figs. 1-2);
a power source of direct current operably linked to the cathode and the anode (a power source would be inherent in order to supply current; Son pp. 8352-54, figs. 1-2);
… wherein the catholyte comprises a saline solution, brackish water, or seawater (water with NaCl; id.).
Son is silent on wherein the membrane is effective to substantially exclude passage of salt ions.
A result-effective variable is a variable which achieves a recognized result. The determination of the optimum or workable ranges of a result-effective variable is routine experimentation and therefore obvious. MPEP § 2144.05.
Son describes membrane permeability. Son p. 8353. A person having ordinary skill in the art would have recognized that the solute concentration difference drives water draw and would have wanted to minimize the salt permeability to maintain this solute concentration difference to maximize water draw, hence making it a result-effective variable. See id.
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have routinely experimented with the variable and determined the optimum or workable range to be inclusive of the claimed range/value(s).
Son is silent on wherein the anolyte comprises a negative ion inert to oxidation.
However, Son describes how either chloride or nitrate (which is inert) may be used as the electrolyte. Son p. 8354, fig. 2.
Therefore, it would have been obvious with a reasonable expectation of success to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the aforementioned prior art’s by combining the chloride with nitrate as either may be used as electrolyte.
3. The system of claim 1, wherein the membrane is a reverse osmosis (RO) membrane (rejected for similar reasons stated in the claim 1 rejection).
5. The system of claim 1, wherein the membrane resists passage of gases (the membrane has a pore size of 0.25 nm so this would resist passage of gases). Son p. 8353.
6. The system of claim 1, wherein the catholyte is in fluid connection to a source of further catholyte (catholyte fed). Son fig. 2.
7. The system of claim 1, wherein the power source applies a direct current to the cathode and the anode to establish an electrical potential between the first chamber and the second chamber, the membrane allowing for production of hydrogen gas at the cathode and oxygen gas at the anode (a constant current was applied to the electrodes, thus it would have been direct current). Son pp. 8352-54, figs. 1-2.
8. The system of claim 1, wherein the anolyte comprises a higher ionic strength than the catholyte, and wherein the membrane allows water molecules to pass from the catholyte to the anolyte to replace water molecules hydrolyzed due to operation of the system (anolyte has higher concentration and the membrane passes water). Son figs. 1-2.
Claims 1-3 and 5-9 are rejected under 35 U.S.C. § 103 as being unpatentable over Son as applied to claim 1 previously, and further in view of Anderson et al., U.S. Patent App. Pub. No. 2012/0305407 A1 [hereinafter Anderson].
1-2. The system of claim 1, wherein the anolyte comprises perchlorate. Son is silent on this. This rejection serves as an alternative rejection to claim 1’s negative ion.
Anderson teaches that chloride and perchlorate both are suitable electrolytes for electrolytic solutions. Anderson [0045].
Therefore, it would have been obvious with a reasonable expectation of success to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the aforementioned prior art’s system by combining the prior art’s chloride with Anderson’s perchlorate to yield the predictable result of having a suitable electrolyte for an electrolytic solution.
3 & 5-9. These claims are rejected for similar reasons stated in their respective claims.
Claim 9 rejected under 35 U.S.C. § 103 as being unpatentable over Son and alternatively in view of Anderson as applied to claim 1 previously, and further in view of Roeth et al., U.S. Patent App. Pub. No. 2002/0170831 A1 [hereinafter Roeth].
9. The system of claim 1, wherein the catholyte is a buffered saline solution. Son is silent on this.
However, Son teaches that a pH range must be maintained for membrane operation. Son p. 8359.
Roeth teaches using a buffer to electrode zones. Roeth [0014], [0076], [0082], [0106], fig. 1. A person having ordinary skill in the art knows that a buffer helps to maintain a desired pH.
Therefore, it would have been obvious with a reasonable expectation of success to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the aforementioned prior art’s catholyte with Roeth’s buffer to maintain the pH within range for membrane operation.
Response to Arguments
Applicant’s latest filed arguments have been fully considered and are addressed below.
The Examiner has considered Applicant’s argument A that Son does not teach to minimize salt permeability. Remarks pp. 13-14.
The Examiner respectfully submits that Son recognizes membrane permeability and then the rest of the motivation comes from what a person having ordinary skill in the art would have known at the time of the invention.
The Examiner has considered Applicant’s argument B that Anderson does not teach the membrane excluding salt ions. Remarks pp. 14-15.
The Examiner respectfully submits that Anderson was not cited for the membrane excluding salt ions as that was addressed in the claim 1 rejection.
The Examiner has considered Applicant’s argument C that Son does not teach active management of pH. Remarks pp. 15-16.
The Examiner respectfully submits that a pH range must be maintained thus a person having ordinary skill in the art would have wanted to ensure that the pH stayed in that range.
The Examiner has considered Applicant’s argument that Roeth does not teach a buffer in a catholyte. Remarks p. 16.
The Examiner respectfully submits that a person having ordinary skill in the art would have had a reasonable expectation of success using a buffer in Son’s teachings since buffers were known to function in aqueous solutions, such as Son’s.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Hosung Chung whose telephone number is (571)270-7578. The examiner can normally be reached Monday-Friday, 9 AM - 5 PM CT.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, James Lin can be reached on (571) 272-8902. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/HOSUNG CHUNG/Primary Examiner, Art Unit 1794
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