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 .
Election/Restrictions
Claims 17- 25 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 06/24/2025.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier.
Such claim limitation(s) is/are: “recycling unit” in Claim 12.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof (references are made to the publication of the instant application):
Per [0054]-[0058], Fig. 2/17: “…the less concentrated brine can be recycled to the forward osmosis system or can be mixed with salt to increase the concentration before being recycled to the forward osmosis system. In certain embodiments, the less concentrated brine 36 can be advanced to other metal extraction processes; or it can be returned to the geothermal brine aquifer”; “The permeate can then be fed back to the forward osmosis system using the pump.” This process, from the figures and passage cited above, entails conduits, pumps, and mixers that recirculate the less concentrated brine to other stages of the process. These elements are considered as covering the corresponding structure described in the specification as performing the claimed function.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
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., Chenging 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.
Claim(s) 7-14 is/are rejected under 35 U.S.C. 103 as being unpatentable over WO2017039724A1, hereinafter ‘Cheng’, in view of US20150090457A1, hereinafter ‘Harrison’.
Regarding Claim 7, Cheng discloses a method of increasing lithium concentration of a lithium containing solution ([0031]: lithium recovery operation is depicted via the referenced figures, in which a concentration operation is depicted; [0010]: the process involves the increasing the concentration of dissolved lithium, or in other words, a lithium containing solution), the method comprising:
providing a lithium containing solution comprising lithium and divalent ions ([0010]: “This invention thus provides as an embodiment a process for producing a high purity aqueous lithium-containing solution from a source of dissolved lithium that also contains at least Na+, Ca2+, and Mg2+ in solution…”; Ca2+ and Mg2+ are divalent ions);
providing at least one osmosis unit having at least one lithium containing solution chamber having at least one first inlet and at least one first outlet, at least one brine chamber having at least one second inlet and at least one second outlet, and at least one selectively permeable membrane positioned between the at least one lithium containing solution chamber and the at least one brine chamber ([0054]: the lithium solution is provided to a forward osmosis unit; [0060]: “The forward osmosis can also be conducted on a continuous basis in a unit (also known as housing) which supports a forward osmosis membrane and divides the unit into a first and second internal chamber. For continuous operation the first chamber receives a continuous or pulsed flow of the lithium solution that passes into, through, and out of the first chamber while causing this lithium solution to contact one side of the membrane. The second chamber receives a continuous or pulsed flow of draw brine solution into, through, and out of the second chamber while causing this draw brine solution to contact the other side of that membrane”; a forward osmosis membrane is a type of selectively permeable membrane; the first and second chambers are configured such that the openings thereto function as both inlets and outlets, as fluid is disclosed as flowing both into and out of said chambers);
conveying the lithium containing solution through the at least one lithium containing solution chamber to concentrate the lithium containing solution ([0060]: “the first chamber receives a continuous or pulsed flow of the lithium solution that passes into, through, and out of the first chamber while causing this lithium solution to contact one side of the membrane… [d]uring operation of the process, water is caused to flux through said semi-permeable forward osmosis membrane…[t]he result is that the lithium concentration of the lithium solution is increased”;
conveying a brine solution through the at least one brine chamber, wherein water from the lithium containing solution is drawn through the at least one selectively permeable membrane and into the brine solution, such that a concentrated lithium containing solution exits through the first outlet and a less concentrated brine solution exits through the second outlet ([0060]: “The second chamber receives a continuous or pulsed flow of draw brine solution into, through, and out of the second chamber while causing this draw brine solution to contact the other side of that membrane…[d]uring operation of the process, water is caused to flux through said semi-permeable forward osmosis membrane as a result of the difference in osmotic pressure between said solutions in said first and second chambers, wherein the water flows from the first chamber to the second chamber. The result is that the lithium concentration of the lithium solution is increased.”; this process results in a concentrated lithium solution, which exists from the first chamber, and a brine solution diluted by the permeated water, which exits from the second chamber).
Further, it is noted that Cheng discloses a step in the process for recovering lithium that is considered a lithium capture step as claimed, in that lithium is extracted from the solution by means of a sorbent and said sorbent is desorbed, thereby producing a lithium rich stream ([0042]-[0043]).
However, this lithium capture step of Cheng is performed prior to forward osmosis concentration, whereas the instant claim requires that the concentrated lithium stream produced by osmosis is subjected to lithium capture. As such, the difference between the process of Cheng and the instantly claimed method is that Cheng performs lithium capture prior to osmosis, whereas the instant method requires lithium capture to occur after osmosis.
However, Cheng discloses that the sorbent can recover lithium from brine of any concentration, and that the higher the initial lithium concentration in the brine, the higher will be the sorbent take-up or load of sorbed lithium when breakthrough has occurred ([0042]), and that after activation, the sorbent is capable of recovering lithium from any lithium-containing brine ([0040]). This implies that the sorbent will effectively capture lithium from any lithium solution, and particularly will adsorb a higher amount of lithium when a more concentrated solution of lithium is contacted therewith, thereby resulting in a higher degree of separation of lithium from the lithium solution. Further, the sorbent utilized by Cheng is disclosed as having “exceptionally good sorbent characteristics, compared to those described in prior arts, in particular, high lithium sorption capacity, rapid lithium sorption and desorption rates, large particle size and thereby low pressure drop in the bed, durable particle integrity, and low preparation cost” ([0040]). From this, it is clear that the sorbent utilized by Cheng has a high affinity for adsorbing lithium in solution, and would be expected to function well when applied to a broad range of lithium-containing solutions, including those that have already been concentrated by forward osmosis.
Therefore, given that Cheng has disclosed that higher concentrations of lithium result in increased adsorbency of lithium in the disclosed sorbent step, given that the forward osmosis process of Cheng has been shown to increase the concentration of the lithium solution, and that the sorbent of Cheng is known to have high sorption capacity for lithium, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to alter the order of process steps to perform the sorbent capture step, considered a lithium capture step, on the concentrated lithium solution resulting from forward osmosis in the process of Cheng. Since the goal of Cheng is to result in a pure stream of lithium chloride ([0009]), such a rearrangement in process steps would predictably result in a higher degree of separation of lithium from the lithium solution, thereby improving the purity and yield of lithium resulting from the disclosed process. As held by the court in In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930), the selection of any order of mixing ingredients is prima facie obvious in the absence of new or unexpected results. As such, absent evidence of such new or unexpected results associated with the sequence of adding ingredients, the claimed process sequence is considered prima facie obvious over the disclosure of Cheng.
Further regarding Claim 7, it is noted that Cheng discloses the use of natural or industrial brines containing lithium as the source of the lithium solution to be concentrated ([0019]).
However, Cheng does not disclose that the lithium containing solution comprises silica.
Harrison discloses a method of removing silica from brines ([0003]). A person of ordinary skill in the art would have recognized Harrison as analogous to Cheng, as both references are drawn to the same field of endeavor as the claimed invention, the treatment of brines - a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Further, Harrison discloses that geothermal brines (also known as “natural brines”, as disclosed in Cheng) very often contain silica, and are “frequently…near saturation with respect to the silica concentration” ([0006]-[0007]). The presence of silica is disclosed as being deleterious to a number of processes utilizing said brines, including reverse osmosis processes (RO), as the presence of silica in these processes result in deposition, polymerization, and coprecipitation with other species that form scale deposits ([0007]). Harrison provides a method for preventing such silica scale in processes utilizing geothermal brines, utilizing a silica precipitate seed, which, when provided prior to flashing the geothermal brine, can lower the amount of silica as low as 160 ppm ([0017]), and subsequently providing this treated brine to a silica management process, in which the content of silica in the brine is reduced further – the use of such a process can prevent, reduce or delay the buildup of scale, thereby increasing the lifetime of the equipment in which the geothermal brine is used ([0018]).
Accordingly, given that the disclosure of Cheng utilizes natural or geothermal brines, the brines utilized by Cheng are considered to encompass brines having a significant amount of silica, an amount that may even be near saturation of said silica in the brine – therefore, the use of brines containing silica in the process of Cheng would be obvious to one of ordinary skill in the art, given the prevalence of silica in natural brines. Being aware of the presence of said silica in natural brines, one of skill in the art utilizing the process of Cheng would have found it obvious to subject the brines utilized in the disclosed process to silica management steps as disclosed by Harrison, including the use of a silica precipitate seed and silica management system, prior to the performance of forward osmosis. The performance of such silica management would predictably reduce the amount of silica in the brine to levels below 160 ppm, thereby preventing any scaling from occurring in the osmosis equipment, thereby extending the lifetime of said equipment.
Regarding Claim 8, Cheng as modified above makes obvious processing the lithium containing solution in a silica management process to remove silica, wherein an amount of silica in the lithium containing solution after the silica management process is less than about 150 ppm (as discussed above, Harrison makes obvious the use of silica management processes to reduce the silica content of geothermal brines to below 160 ppm – this range of silica concentration (0-160 ppm) overlaps and makes obvious the instant claimed range. As set forth in MPEP 2144.05, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art,” a prima facie case of obviousness exists, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) – as such, the instant claimed range is obvious over the prior art range).
Regarding Claim 9, Cheng as modified above makes obvious the lithium capture step comprises contacting the concentrated lithium containing solution with a sorbent (as discussed above, the lithium capture step of Cheng utilizes a sorbent).
Regarding Claim 10, Cheng as modified above makes obvious a portion of eluate obtained from the sorbent is recycled to the sorbent to increase a ratio of lithium to sodium in the lithium rich stream ([0090]-[0093]: the lithium capture step is performed cyclically, where the lithium brine is passed in and out of the adsorption column a total of 16 times – this is considered to meet recycling a portion of eluate obtained from the sorbent back to the sorbent, thereby increasing a ratio of lithium to sodium in the lithium rich stream).
Regarding Claim 11, Cheng as modified above makes obvious the concentrated lithium containing solution exiting the at least one first outlet has a concentration of lithium chloride of at least about 15 weight % based on the total weight of the concentrated lithium containing solution ([0044]: “The concentration of lithium chloride solution should also be increased to about…10% or more” – this range (10% - 100% concentration of lithium) overlaps with and makes obvious the instant claimed range).
Regarding Claim 12, Cheng as modified above makes obvious supplying the less concentrated brine solution exiting the at least one second outlet to a recycling unit ([0061]: “Countercurrent or concurrent directional flow of the lithium solution and/or draw brine solution may occur as (i) recirculated flow, (ii) continuous flow, (iii) pulsed flow, or (iv) a combination of any two of these flows:; “[0099]: “…a four liter quantity of a brine used as a draw solution was recirculated through the second chamber of the CF042 cell using a peristaltic pump at a flow rate of 1 liter per minute” – such recirculation via a pump is considered supplying the less concentrated brine solution exiting the at least one second outlet to a recycling unit (the pump, in this case, is considered a recycling unit according to the interpretation of this term set forth above) – given that recirculation is disclosed as a suitable method of flow for the draw brine solution, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to utilize a recirculation flow, as such a means of operation is within the scope of the disclosed invention and would yield predictable results, i.e., the concentration of the lithium solution).
Regarding Claim 13, Cheng as modified above makes obvious recovering lithium from the lithium capture step to produce the lithium rich stream ([0043]: lithium is desorbed from the sorbent, thereby recovering lithium from the lithium capture step to produce a lithium rich stream).
Regarding Claim 14, Cheng as modified above makes obvious purifying the lithium rich stream to remove divalent ions and borate ions ([0103]: Cheng discloses a treatment comprising adding a base solution to a lithium solution, resulting in the precipitation and filtration of divalent ions such as Ca2+ and Mg2+ - in light of this, and given Cheng’s objective of producing a pure lithium chloride stream, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to perform such a precipitation step to remove divalent ions from the lithium rich stream, thereby producing a more pure lithium chloride stream; [0104]: Cheng discloses the use of boron selective ion exchange resins, which are applied to a lithium solution in order to remove boron ions, which would include borate ions - in light of this, and given Cheng’s objective of producing a pure lithium chloride stream, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to utilize such an ion exchange resin to remove boron ions, such as borate, from the lithium rich stream, thereby producing a more pure lithium chloride stream).
Claim(s) 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over WO2017039724A1, hereinafter ‘Cheng’, in view of US20150090457A1, hereinafter ‘Harrison’, and further in view of US2726138A, hereinafter ‘Cunningham’.
Regarding Claims 15 and 16, it is noted that, while the process of Cheng discloses methods for producing a pure stream of lithium chloride ([0009]), each example disclosed by Cheng shows significant amounts of sodium impurities not removed by the process (Tables 1-4).
However, Cheng as modified above does not disclose concentrating the lithium rich stream to produce a twice concentrated lithium rich stream, or purifying the twice concentrated lithium rich stream by removing sodium and potassium ions to produce a concentrated lithium rich solution having reduced sodium and potassium ion concentrations.
Cunningham discloses a process for the purification of solutions comprising lithium chloride and a substantial concentration of potassium and/or sodium (Col 1, lines 15-19). A person of ordinary skill in the art would have recognized Cunningham as analogous to Cheng and Harrison, as both references are drawn to the same field of endeavor as the claimed invention, the purification of lithium solutions - a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Further, Cunningham discloses the process for removing sodium and potassium comprises evaporating said solution to obtain a solution having about 40-44% lithium, cooling the solution to about 25 °C, filtering the solution to remove solid sodium and potassium formed by said cooling, and contacting the resulting solution with an inert water insoluble polar organic selective solvent for the initial lithium chloride, separating the extract phase and recovering therefrom high purity lithium chloride (Col 1, line 67 – Col 2, line 7).
Given this, and given Cheng’s objective of producing a pure lithium chloride stream, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to perform the sodium and potassium removal process as disclosed by Cunningham on the lithium rich stream obtained from desorption of the sorbent in Cheng. Such a process would predictably reduce the levels of sodium impurities in the solution, thereby producing a lithium chloride solution with higher purity than that which could be achieved using the methods of Cheng alone. Further, the process of Cunningham, as discussed above, comprises a concentration step (i.e., evaporation to obtain 40-44% LiCl) that would result in a twice concentrated solution, as required by Claim 15, and further would result in the removal of sodium and potassium impurities subsequent to this second concentration, as required by Claim 16.
Response to Arguments
Applicant’s arguments, filed 02/10/2026, are acknowledged.
With respect to arguments with regard to the rejection of Claim(s) under section 112(b), the arguments have been fully considered and are persuasive. These rejections have been withdrawn.
With respect to arguments in regard to prior art rejections under section 103, Applicant’s arguments have been fully considered but are not persuasive. These rejections, as repeated above, are maintained.
Applicant argues that “[i]n some aspects, the claimed subject matter can concentrate lithium chloride containing solutions by removing water, and also concentrating other metal salt solutions like manganese, zinc, and other metals to facilitate their recovery from brines. This is not taught or disclosed by Cheng. Taking the disclosure of Cheng, one of ordinary skill in the art would have no motivation to provide a process in which lithium capture occurs after osmosis as presently claimed” (Remarks, page 8).
This is not persuasive, as Applicant has not argued against the modification of Cheng as presented in the prior Office action, now repeated above. The rejection establishes a motivation for performing lithium capture following forward osmosis as claimed:
“…given that Cheng has disclosed that higher concentrations of lithium result in increased adsorbency of lithium in the disclosed sorbent step, given that the forward osmosis process of Cheng has been shown to increase the concentration of the lithium solution, and that the sorbent of Cheng is known to have high sorption capacity for lithium, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to alter the order of process steps to perform the sorbent capture step, considered a lithium capture step, on the concentrated lithium solution resulting from forward osmosis in the process of Cheng. Since the goal of Cheng is to result in a pure stream of lithium chloride ([0009]), such a rearrangement in process steps would predictably result in a higher degree of separation of lithium from the lithium solution, thereby improving the purity and yield of lithium resulting from the disclosed process.”
Applicant has not pointed out any supposed error in this line of reasoning. Since such a modification would clearly result in a higher degree of separation of lithium from the lithium solution, thereby improving the purity and yield of lithium resulting from the disclosed process, one of ordinary skill in the art would be motivated to perform such a modification to achieve these benefits.
Further, regarding Applicant’s argument that “[i]n some aspects, the claimed subject matter can concentrate lithium chloride containing solutions by removing water, and also concentrating other metal salt solutions like manganese, zinc, and other metals to facilitate their recovery from brines. This is not taught or disclosed by Cheng”, it is noted that the features upon which applicant relies (i.e., concentrating other metal salt solutions like manganese, zinc, and other metals to facilitate their recovery from brines) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Further, in response to applicant' s request to hold in abeyance a response, such as, a terminal disclaimer (TD) to the pending double patenting rejection, it is noted that the filing of a TD cannot be held in abeyance since that filing “is necessary for further consideration of the rejection of the claims” as set forth in MPEP 804 (I) (B) (1) quoted below:
“As filing a terminal disclaimer, or filing a showing that the claims subject to the rejection are patentably distinct from the reference application' s claims, is necessary for further consideration of the rejection of the claims, such a filing should not be held in abeyance. Only objections or requirements as to form not necessary for further consideration of the claims may be held in abeyance until allowable subject matter is indicated.”
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.
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LOGAN LACLAIR
Examiner
Art Unit 1736
/L.E.L./ Examiner, Art Unit 1736
/ANTHONY J ZIMMER/ Supervisory Patent Examiner, Art Unit 1736
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