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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 01/20/2026 has been entered.
Status of the Claims
This is a non-final Office action in response to the Applicant’s arguments and amendments filed on 01/20/2026. Claims 27-29 and 32 are pending in the current office action. Claims 27-29 and 32 were amended by Applicant.
Status of the Rejection
The rejections of claims 27-29 and 32 under 35 U.S.C. § 112(b) are withdrawn in view of Applicant’s amendments.
The rejections of claims 27-29 and 32 under 35 U.S.C. § 103 are withdrawn in view of Applicant’s amendments.
New rejections of claims 27-29 and 32 are necessitated by Applicant’s amendments.
Claim Objections
Claims 27 and 28 are objected to because of the following informalities:
Claim 27 line 12 recites “at least said first and second electrodialysis devices is”, but should recite “at least said first and second electrodialysis devices [[is]] are” to be grammatically correct;
Claim 28 line 2 recites “devices]”, but should recite “devices” to correct the typo.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The text of those sections of Title 35, U.S. Code not included in this action i.e., the text of 35 U.S.C. § 112(a), can be found in a prior Office action.
Claims 27-29 and 32 are rejected under 35 U.S.C. 112(a) as failing to comply with the written description requirement. The claims contain 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 at the time the application was filed, had possession of the claimed invention.
Regarding claim 27, claim 27 recites the limitation “at least one of said electrodialysis devices comprises a bipolar membrane …” in lines 8-11. These limitations are not supported by the specification. Specifically, as previously indicated in the Office actions dated 06/26/2024 and 06/20/2025 and acknowledged by Applicant in the interview on 12/03/2024, the specification does not include any reference to the use of “bipolar membranes”.
These limitations of claim 27 are therefore considered to be new matter not supported by the specification as originally filed.
Claim 27 is therefore rejected under 35 U.S.C. 112(a) for failing to comply with the written description requirement due to containing new matter.
Regarding claim 28, claim 28 recites the limitation(s) “first, second, and third electrodialysis units are arranged in series to operate at a current density below a limiting current density to minimize water splitting and boron transport” in lines 2-4. Support for this/these limitation(s) could not be identified in the specification as originally filed.
Specifically, while the specification describes limiting boron transport in e.g., paras. 99-100, it attributes this result to the use of pH control and the ionic membranes, not to the current density. No reference to “current density” or a “limiting current” could be identified in the specification, whether in the context of limiting boron transport or otherwise. Furthermore, the specification does not appear to describe “water splitting” whatsoever.
The limitation(s) “first, second, and third electrodialysis units are arranged in series to operate at a current density below a limiting current density to minimize water splitting and boron transport” is therefore considered to be new matter not supported by the specification as originally filed.
Furthermore, claim 28 depends from claim 27, and thus incorporates the new matter of claim 27.
Claim 28 is therefore rejected under 35 U.S.C. 112(a) for failing to comply with the written description requirement due to containing new matter.
Regarding claim 29, claim 29 depends from claims 27 and 28, and thus incorporates the new matter of those claims.
Claim 29 is therefore rejected under 35 U.S.C. 112(a) for failing to comply with the written description requirement due to containing new matter.
Regarding claim 32, claim 32 depends from claim 27, and thus includes the new matter recited in claim 27.
Claim 32 is therefore rejected under 35 U.S.C. 112(a) for failing to comply with the written description requirement due to containing new matter.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 27-29 are rejected under 35 U.S.C. 103 as being unpatentable over Liang (US Pat. Pub. 2021/0340031) in view of Perez (US Pat. Pub. 2013/0126353 A1), and Chen (US Pat. No. 3223612 A1).
Regarding claim 27, Liang teaches a water treatment system (“A water treatment system” abstract) comprising:
at least a first electrodialysis device, a second electrodialysis device, and a third electrodialysis device arranged in series (“first … electrochemical separation substages 311 …, each sub-stage comprising a plurality of electrochemical separation modules,” para. 51, “The first stage includes two sub-stages of electrodialysis modules, each sub-stage having 36 electrodialysis modules,” para. 61 and Fig. 3 i.e., the “first electrochemical separation substage 311” comprises thirty-six electrodialysis devices arranged in series);
wherein each of said first, second, and third electrodialysis devices comprises a plurality of alternating anion-exchange membranes and cation-exchange membranes defining alternating diluate and concentrate compartments (“the subblocks were arranged in two passes, each with 4 sub-blocks as defined herein.” para. 61, “Each electrochemical separation module may be assembled from a plurality of … sub-blocks. Each sub-block may contain from 1 to 10, … cell pairs” para. 31, and “A set of a dilution compartment, a cation selective membrane, a concentration compartment, and an anion selective membrane may be called a cell pair” para. 24 i.e., each electrodialysis device of the “first electrochemical separation substage 311” comprises 4 pairs of alternating anion-exchange and cation-exchange membranes defining alternating diluate and concentrate compartments);
wherein at least said first and second electrodialysis devices are configured to receive a portion of said feed stream (“The first stage modules were configured to receive brackish water as feed” para. 61 i.e., each first stage module receives a portion of the feed stream) and produce a concentrate stream and a diluate stream (“each having a dilution compartment and a concentration compartment” para. 61);
wherein the diluate stream from said first electrodialysis device is fed as a portion of the feed stream to said second electrodialysis device in the series (“A plurality of sub-blocks may also be arranged so that the dilution stream and the concentration stream flow through their respective compartments in each sub-block in series. The flow path through each sub-block is herein called a pass.” para. 32 and “the subblocks were arranged in two passes” para. 61).
The preamble limitation “A water treatment system for recovering lithium from a feed stream comprising lithium and boron,”, as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case, Liang teaches a system comprising a plurality of electrodialysis units arranged in series configured to remove ionic compounds from brine. The instant specification teaches that a system comprising a plurality of electrodialysis arranged in series is capable of recovering lithium from a feed stream comprising lithium and boron. The system of Liang is therefore considered to be capable of recovering lithium from a feed stream comprising lithium and boron.
As the system of Liang is capable of recovering lithium from a feed stream comprising lithium and boron, the system of Liang reads on the limitation “A water treatment system for recovering lithium from a feed stream comprising lithium and boron” as currently drafted.
Liang does not teach at least one of said electrodialysis devices comprises a bipolar membrane having a cation exchange side and an anion exchange side.
However, Perez teaches a water treatment system (see title) comprising electrolysis devices (“electrodialysis device (14)” para. 19 and Figs. 1, 3 and “Bipolar electrodialysis device (24)” para. 20 and Figs. 1, 4) wherein a portion of said electrodialysis devices comprise a bipolar membrane having a cation exchange side and an anion exchange side (“bipolar membrane (206)” para. 38 and Fig. 4), which provides the predictable benefit of controlling the pH of the desalinated product water (see paras. 39-40).
As Liang and Perez each teach electrodialysis systems, Liang and Perez are analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the system of Liang, such that at least one of said electrodialysis devices comprises a bipolar membrane having a cation exchange side and an anion exchange side, as taught by Perez. A person having ordinary skill in the art would have been motivated to make this modification to achieve the predictable benefit of controlling the pH of the output stream(s), as taught by Perez. Furthermore, combining prior art elements to produce a predictable result establishes a prima facie case of obviousness (MPEP § 2143(I)(A)).
Modified Liang does not explicitly teach a spacer disposed on at least one surface of said bipolar membrane facing an ion-exchange membrane, the spacer including a spacer border and a spacer mesh forming intermembrane chambers to create a path for fluids to flow.
However, Chen teaches a water treatment system (see title) comprising:
an electrodialysis device (see col. 1 lines 10-13) wherein the ion exchange membranes have a spacer on at least one surface facing an ion-exchange membrane (“a cation permeable membrane 48K with suitable manifold spacers 60 … an anion permeable membrane 48A with suitable manifold spacers 60,” col. 4 lines 73 – col. 5 line 1 and Fig. 3) that includes a spacer border (comprising “base 49” and “cover 55” see Figs. 4-12) and a spacer mesh forming intermembrane chambers to create a path for fluids to flow (“screen spacer 57” Figs. 6, 8, 9 and 11), wherein the spacers provide the predictable benefit of allowing membranes that do not have flow apertures to be used in the system (“thicker manifold spacer portions containing manifold apertures so that membranes, which do not contain any manifold or fluid flow apertures for example, may be interspersed between the gaskets” col. 2 lines 4-8).
As Chen teaches a water treatment system using electrodialysis, Chen is analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the system of Liang, such that a spacer is disposed on at least one surface of said bipolar membrane facing an ion-exchange membrane, the spacer including a spacer border and a spacer mesh forming intermembrane chambers to create a path for fluids to flow. A person having ordinary skill in the art would have been motivated to make this modification to enable membranes without flow apertures to be used in the system of Liang, as taught by Chen. Furthermore, combining prior art elements to produce a predictable result establishes a prima facie case of obviousness (MPEP § 2143(I)(A)).
Regarding claim 28, the limitation “at least one of said electrodialysis devices is configured to operate at a current density below a limiting current density to minimize water splitting and boron transport”, as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case, Liang teaches that the system comprises a control system and sensors to adjust the current supplied to the electrodialysis devices (para. 42). The system of Liang is therefore capable of operating at a current density below a limiting current density to minimize water splitting and boron transport.
As the system of Liang is capable of operating at a current density below a limiting current density to minimize water splitting and boron transport, Liang reads on the limitation “at least one of said electrodialysis devices is configured to operate at a current density below a limiting current density to minimize water splitting and boron transport”.
Regarding claim 29, Liang further teaches the feed stream to said first electrodialysis device is a combination of fresh feed and a recycle stream from subsequent electrodialysis devices (“the product of the second electrochemical stage 320 back to the first feed line 300 of the system through fourth feed line 303” para. 54 and Fig. 3).
The limitation “said feed stream to said first electrodialysis device is a combination of fresh feed and a recycle stream from subsequent electrodialysis devices to reduce water usage” (emphasis added), as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case, Liang teaches the feed stream to said first electrodialysis device is a combination of fresh feed and a recycle stream from subsequent electrodialysis devices. The system of Liang is therefore capable of reducing water usage by combining the fresh feed with the recycle stream.
As the system of Liang is capable of reducing water usage by combining the fresh feed with the recycle stream, Liang reads on the limitation “said feed stream to said first electrodialysis device is a combination of fresh feed and a recycle stream from subsequent electrodialysis devices to reduce water usage” as currently drafted.
Claim 32 is rejected under 35 U.S.C. 103 as being unpatentable over Liang in view of Perez and Chen, as applied to claim 27 above, and further in view of Batchelder (US Pat. Pub. 2007/0215474 A1).
Regarding claim 32, modified Liang renders the limitations of claim 27 obvious, as described above.
The limitation “such that a pH of said feed stream fed to at least the first, second, and third electrodialysis devices is maintained at or below 9.23.”, as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case Liang (or modified Liang) does not teach the system is capable of maintaining the feed stream to at least the first, second, and third electrodialysis devices is maintained at or below 9.23.
However, Liang further teaches a controller configured to monitor the pH of the water in the system (see para. 42).
Furthermore, Batchelder teaches a water purification system (see e.g., abstract and para. 2) comprising:
electrodialysis devices (“ED or EDI stages 32, 34, 36, 38 and 40” Fig. 2) wherein the pH of each of the fluid streams is controlled (“a caustic or acid injection or production unit may be positioned along the feed or concentrate line to adjust the pH” para. 71).
As Batchelder teaches a water purification system comprising electrodialysis units, Batchelder is analogous art.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to further modify the system of modified Liang to comprise caustic or acid injection units positioned along the feed and concentrate lines. A person having ordinary skill in the art would have been motivated to make this modification to enable the controller of Liang to adjust the pH of the feed streams in response to the pH measurements. Furthermore, combining prior art elements to produce a predictable result establishes a prima facie case of obviousness (MPEP § 2143(I)(A)).
Thus, it would have been obvious to a person having ordinary skill in the art to modify the system of Liang such that it is capable of maintaining the feed stream to at least the first, second, and third electrodialysis devices is maintained at or below 9.23. Modified Liang therefore renders obvious the limitation “such that a pH of said feed stream fed to at least the first, second, and third electrodialysis devices is maintained at or below 9.23” as currently drafted.
Response to Arguments
Applicant’s arguments, see Remarks p. 2, filed 01/20/2026, regarding the rejections of claims 27-29 and 32 under 35 U.S.C. § 112(b), have been fully considered and are persuasive. The rejections of claims 27-29 and 32 under 35 U.S.C. § 112(b) have therefore been withdrawn.
Applicant's arguments, see Remarks p. 2-3, filed 01/20/2026, regarding the rejections of claims 27-29 and 32 under 35 U.S.C. § 103 have been considered, but they are not persuasive.
Applicant’s Argument #1
Applicant argues on p. 2 that, based on the prior art of record, a person having ordinary skill in the art would not have had a particular motivation to modify the system of Liang such that the pH is maintained below 9.23, as recited in claim 32.
Examiner’s Response #1
Examiner respectfully disagrees. At issue is the broadest reasonable interpretation of the limitation “such that a pH of said feed stream fed to at least the first, second, and third electrodialysis devices is maintained at or below 9.23”.
Claim 32 is drawn to an apparatus, and the limitation “such that a pH of said feed stream fed to at least the first, second, and third electrodialysis devices is maintained at or below 9.23” is drawn to a function of said apparatus. For claims drawn to an apparatus, the broadest reasonable interpretation is a system capable of performing the recited function (MPEP § 2114(II)).
Thus, under the broadest reasonable interpretation, the prior art need not teach maintaining the pH at or below 9.23, but need merely teach a system capable of maintaining the pH at or below this value.
In the instant case, it is considered that a person having ordinary skill in the art would have had a motivation to modify the system of Liang such that it is capable of controlling the pH of the feed stream based on the teachings of Batchelder, as detailed in the rejection of claim 32, above.
As Applicant has not provided any rationale for why a person having ordinary skill in the art would not have been motivated to enable the system of Liang to control the pH, Applicant’s argument is not persuasive.
Applicant’s Argument #2
Applicant argues on p. 2-3 that the use of spacers for fluid flow in combination with bipolar membranes provides an unexpected benefit not suggested by the prior art in the instant invention.
Examiner’s Response #2
Examiner respectfully disagrees. In order for unexpected results to overcome a prima facie case of obviousness, Applicant must provide evidence that has a nexus to the claimed invention (MPEP § 716.01(b)), such evidence must be commensurate in scope with the claims (MPEP § 716.02(d)), the evidence must demonstrate a benefit over the closest prior art (MPEP § 716.02(e)), and Applicant must demonstrate that any such benefit demonstrated is, in fact, unexpected (MPEP § 716.02(b)(I) and 716.02(c)).
In the instant case, while Applicant has alleged unexpected benefits from the use of membrane spacers in combination with bipolar membranes, Applicant has not indicated what these benefits are, or provided any evidence supporting their existence. Furthermore, as the instant invention does not, in fact, comprise bipolar membranes, it is unclear how any such benefit could be attributed to their usage.
Applicant’s argument is therefore not persuasive.
Applicant’s Argument #3
Applicant argues on p. 3 that a person having ordinary skill in the art would not have had a motivation to combine the spacers of Chen with the system of Liang. Specifically, Applicant argues that a person having ordinary skill in the art would not have been motivated to make this combination to improve boron rejection in a multi-stage arrangement.
Examiner’s Response #3
Examiner respectfully disagrees. At issue is whether a person having ordinary skill in the art would have found it obvious to modify the system of Liang by using spacers, as taught by e.g., Chen.
While Applicant argues that a person having ordinary skill in the art would not have been motivated to make this modification to improve boron rejection in a multi-stage arrangement, this is not the appropriate legal standard. Rather, the legal standard is whether a person having ordinary skill in the art, before the effective filing date of the instant application, would have expected the proposed modification to result in a benefit (MPEP § 2143(I)(G)), regardless of whether the benefit is the same one asserted by Applicant (MPEP § 2144(IV)).
In the instant case, the use of spacers to provide flow-paths between membranes in electrodialysis systems provides the well-known benefit of removing the need for membrane perforations, as described in e.g., Chen (see rejection of claim 27, above). Thus, a person having ordinary skill in the art would have expected modifying the system of Liang to include such spacers to provide this benefit. It is therefore considered that a person having ordinary skill in the art would have had a strong motivation to make this proposed modification (MPEP § 2144(II)).
As a person having ordinary skill in the art would have had a motivation to modify the system of Liang to comprise spacers based on the teachings of Chen, Applicant’s argument is not persuasive.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALEXANDER R PARENT whose telephone number is (571)270-0948. The examiner can normally be reached M-F 11:00 AM - 6 PM EST.
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/ALEXANDER R. PARENT/Examiner, Art Unit 1795
/LUAN V VAN/Supervisory Patent Examiner, Art Unit 1795