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 .
Response to Amendment
The amendment filed 3/20/2026 has been entered. Claims 2 and 3 have been cancelled. Claims 1 and 4-20 are pending in the application. Claims 11-20 remain withdrawn as directed to a non-elected invention.
The 102(a)(1) rejection of claim 1 previously set forth is withdrawn in view of the amendment.
Response to Arguments
Applicant's arguments filed 3/20/2026 have been fully considered but they are not persuasive at least with respect to the ground of rejection previously applied to claims 2 and 3, and currently applied to amended claim 1 incorporating the same subject matter.
As noted in the rejection of record, “’[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.’ In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).” The combination of Oklejas, Jr. and He disclose the general conditions of the claim i.e. a concentrate series of membranes with internal pressure boosting, and applications involving the use of systems of that general type for concentration and recovery of lithium. Because of this, discovering the optimal or workable ranges for operational conditions such as employed pressures represents an obvious optimization for one of ordinary skill in the art. As discussed in the rejection of record, Oklejas, Jr. already explains the result-effective nature of the operating pressure values at each membrane stage – that higher concentrations of stream carry higher osmotic pressures and therefore the operating pressure determines the net driving pressure of the membrane and, as a consequence, the permeate production [0010] (which would also represent a degree of concentration that each stage could achieve – as concentration requires removal of permeate). Optimization of a result effective variable is obvious to one of ordinary skill in the art and does not represent impermissible hindsight reasoning.
Examiner also disagrees that the prior art as a whole does not teach or suggest higher pressures. While Oklejas, Jr. may suggest that a net driving pressure of 350 psi or the like is typical, there is no indication that this is the only value that would be workable; further, even if this does represent an ideal value, Oklejas, Jr. makes clear that the applied pressure to achieve any given net driving pressure would vary greatly depending upon feed concentration [0004]. Further, while He may provide examples targeting around 1000 psi (6.9 MPa), He also teaches that, depending upon the membrane technology used, the highest operating pressure may reach as high as 16 MPa (over 2300 psi) [pgs. 8-9, spanning paragraph].
Finally, while He may suggest that it is viable to operate the system in a staged manner at constant pressure (such that the intermediate pumps serve only to recover pressure lost to each stage), this is not a teaching or suggestion that operating at successively increased pressures would be improper or unworkable; He provides as specific example of an implementation that provides a useful process at e.g. low cost; however, ‘[a] given course of action often has simultaneous advantages and disadvantages, and this does not necessarily obviate motivation to combine.’" (quoting Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1165, 77 USPQ2d 1865, 1870 (Fed Cir. 2006) (citation omitted))) – see MPEP 2141.02 VI. Oklejas, Jr. already establishes the working principal that increasing concentration carries a corresponding increase in osmotic pressure, and therefore the overall operating pressure should be increased in order to maintain a particular net driving pressure, and that doing so in a staged manner still represents a relatively efficient means of operating.
In view of this, considering the prior art as a whole and in particular given the guidance of Oklejas, Jr., optimization of the established result-effect variable that is the operating pressure (and/or the related net driving pressure) would still have been obvious to one of ordinary skill in the art when considering the combination of Oklejas, Jr. and He, and the invention of claims 1 and 4-10 would have been obvious to one of ordinary skill in the art on this basis and for the reasons otherwise outlined in the rejections below.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1 and 4-10 are rejected under 35 U.S.C. 103 as being unpatentable over Oklejas, Jr (US PGPub 2020/0239337 A1) in view of He et al (CN 112108001 A).
With respect to claims 1, 4, and 6, Oklejas teaches various embodiments of multi-stage membrane processes employing e.g. RO membranes which include intermediate boost pumps, and membranes arranged in concentrate series i.e. a feed fed to a first membrane is split into a permeate and a concentrate, and the concentrate from the first membrane is fed to a boost pump feeding to a second membrane, and so on. Further, in embodiments, the concentrate of at least one stage (e.g. concentrate 672) is fed to a set of energy recovery devices (e.g. turbines 666, 646, and 636) which connect with the aforementioned boost pumps (662, 642, and 634 respectively) [0058-0059, Fig. 6B]. The permeate of the membrane stages e.g. of a series of three membrane stages is connected to a common outlet manifold (640) [0056].
Oklejas therefore properly teaches an arrangement of membrane stage operations consistent with the claim requirement i.e. providing at least three in series, providing concentrate staging between the series, and providing boost pumps and energy recovery according to the claim requirements. Oklejas essentially differs from the instant claimed invention in that Oklejas does not teach that the system is designed for the purpose of recovering a metal, mineral, salt, and/or lithium compound, and therefore does not teach recovering such a compound from the ultimate concentrate stream.
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However, it is well known in the art that brine which may be treated by systems such as RO systems can contain materials which are useful and therefore which are valuable to recover from a concentrated output. He teaches an example process in which various RO stages are used to concentrate a brine containing valuable lithium [Abs], which is recovered from the concentrate discharge of one of the downstream units [pg. 9, step S13].
It would have been obvious to one of ordinary skill in the art to modify the process taught by Oklejas to employ it on a stream containing a valuable material (such as lithium) for which brine concentration may assist recovery because, as in He, series of RO membranes are a cost-effective way to improve recovery of these materials which have separate value.
Applicant amended to require first and second stage pressure boosting pumps and operating ranges for each of the membranes i.e. 100-600 psi for the first membrane, 1000-1200 psi for the second membrane, and 1500-1800 psi for the third. Oklejas teaches that for concentrate-series systems such as those taught, the increase in dissolved solid concentration from stage to stage results in a higher osmotic pressure and lower net driving pressure for each subsequent stream, and thus this must be compensated for by increasing the feed pressure [0010] and that this is ameliorated by employing boost pumps between the stages [0013] to compensate for the change in osmotic pressure, and that this is supplemented using energy recovery turbochargers [0014].
Oklejas is silent to the specific claimed pressure ranges or boosting percent as claimed. However, because Oklejas already identifies the relevant working principle i.e. the relationship between pressure, concentration, and recovery, and the need to increase pressure as the system progresses, optimization of the specific operating pressures (and associated pump boosts/energy recovery rates) for each individual stage would have been obvious to one of ordinary skill in the art. See MPEP 2144.05 II.A; “’[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.’ In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).”
With respect to claim 5, as above Oklejas teaches turbines as part of turbocharger (/turbopump) constructions for energy recovery.
With respect to claim 7, as above the membranes are reverse osmosis (RO) membranes.
With respect to claim 8, as above Oklejas teaches combining the permeate to a common manifold.
With respect to claim 9, He teaches that the feed may be a lithium chloride containing brine with concentration in a range of 10-2000 mg/L [pg. 3, last paragraph] which would overlap the claimed range regarding lithium content in the feed. As above, as taught by Oklejas, the concentrate and recovery rate of the overall system would depend upon the operating pressure, and optimization e.g. to balance recovery/concentration rate with factors such as energy requirements and other costs would have been obvious to one of ordinary skill in the art.
With respect to claim 10, He teaches that salt lake brine represents the most common source of lithium salt [pg. 2, first paragraph] such that it would have been obvious to one of ordinary skill in the art to apply the modified process of Oklejas to salt lake brine sources for the purpose of recovering useful materials such as lithium, as suggested by He.
Conclusion
THIS ACTION IS MADE FINAL. 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 BRADLEY R SPIES whose telephone number is (571)272-3469. The examiner can normally be reached Mon-Thurs 8AM-4PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jennifer Dieterle can be reached at (571)270-7872. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/BRADLEY R SPIES/Primary Examiner, Art Unit 1777
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