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 Arguments
Applicant’s arguments, see Page 5, line 7 - Page 6, line 10, filed December 15th, 2025, with respect to the rejections of claims 18-26 under 35 U.S.C. 102(a)(1) and 103 have been fully considered and are persuasive. Due to claim amendments, the rejection has been withdrawn. However, new grounds of rejection are made in view of the prior art over the newly added claims 33-34 and 36-37.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 33-34 and 37 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Xu (CN 110042262 A, 2019) (the machine translation of record is referenced below).
Regarding claim 33, Xu teaches a method of leaching lithium into a solution (Xu, [0031], [0043]), the method comprising:
exposing sedimentary ore comprising a lithium species (Xu, [0035], [0043], Guizhou sedimentary lithium ore) to an acid and an oxidant Xu, [0035], nitric acid [0043], sulfuric acid; nitric acid and sulfuric acid are both acids and oxidants), wherein the acid has a concentration of 2.0 mol/L (Xu, [0035], 3.0 mol/L nitric acid) or 2.5 mol/L (Xu, [0043], 2.5 mol/L sulfuric acid);
flowing a liquid across the sedimentary ore, the acid, and/or the oxidant (Xu, [0035], [0043], ore is placed in solution. Since ore would have a higher density than the solution, it would fall to the bottom in the absence of stirring, constituting flowing the liquid across the ore. If stirring is alternatively performed, the liquid would continuously flow past the ore. Therefore, the liquid flows across the ore whether or not stirring is performed.); and
dissolving at least a portion of the lithium species into the liquid to form a leachate (Xu, [0035], lithium element leaching rate was 96.67%; [0043], lithium element leaching rate was 95.33%).
Regarding claim 34, Xu teaches the method of claim 33, as discussed above, further comprising suspending the sedimentary ore in a solution comprising the acid and/or the oxidant (Xu, [0035], [0043], ore is 200 mesh size and placed in solution, thereby forming a suspension).
Regarding claim 37, Xu teaches the method of claim 33, as discussed above, wherein dissolving at least a portion of the lithium species comprises selectively dissolving the lithium species (Xu, [0035], lithium element leaching rate was 96.67%, and silicon leaching rate was <5%; [0043], lithium element leaching rate was 95.33%, and silicon leaching rate was <5%).
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.
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 36 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (CN 110042262 A, 2019) (see the machine translation of record), as applied to claim 33 above, and further in view of Rabe (WO 2020/205302 A1).
Regarding claim 36, Xu teaches the method of claim 33, as discussed above, but does not explicitly teach flowing the leachate to one or more chambers or an electrodialysis stack. Moreover, Xu does not describe the solid-liquid separation for obtaining the leachate in detail (Xu, [0035], [0043]). However, Rabe teaches that obtaining the leachate of a similar process can be achieved by flowing the leachate to one or more chambers (Rabe, Fig. 3, [0025], “The acidified slurry 212 is then pumped to the recessed chamber membrane filter press until the filter press chambers are filled with filter cake.”).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to have, in Xu’s method, adopted Rabe’s separation which flows the leachate to one or more chambers. The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art (see MPEP 2143.A.). The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 - 97 (2007) (see MPEP § 2143.B.). In the instant case, flowing the leachate to one or more chambers would yield the predictable result of separating the leachate from the remaining solids in the spent slurry of Xu. A person having ordinary skill in the art would have been motivated to look to the prior art to achieve this implicit separation of Xu, as Xu provides little detail in how the separation was performed (Xu, [0035], [0043]).
Allowable Subject Matter
Claims 18-32 are allowed.
Claim 35 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: Rabe (WO 2020/205302 A1), Birk (“Sulfate ion (SO42-)”, 2019), Howling (U.S. Patent No. 3,099,527, 1963), Xu (CN 110042262 A, 2019) (see the machine translation of record), Pereira (U.S. 2007/0209481 A1), Xi (CN 104495880 A, 2015) (the attached machine translation is referenced below) and Peng (CN 1687468 A, 2005) (the attached machine translation is referenced below) are considered to be the closest prior art to the instant claims.
Regarding claim 18 and its dependent claims 19-26, Rabe teaches leaching lithium from a sedimentary ore by exposing the ore to an acid and an oxidant, as discussed on Page 3, lines 1-18 of the Office Action dated August 15th, 2025, as does Xu, as discussed in the rejection of claim 33 under 35 U.S.C. 102 above. Additionally, Pereira teaches percolation of the acidic lixiviant through solid ore as a viable strategy (Pereira, [0026]-[0027]). However, none of the cited prior art references teach or suggest that the oxidant is also in the solid state for leaching lithium from a sedimentary ore. The closest prior art teaching in Peng states that solid sodium persulfate can be used as an oxidant for leaching nickel from a mixture including nickel matte and ore pulp (Peng, [004]), but there is no teaching or suggestion that this would be effective in a lithium leaching process or applicable to a leaching involving percolation of the acid through the ore. A person having ordinary skill in the art would therefore not have a reasonable expectation of success applying percolation and a solid oxidant to lithium leaching from a sedimentary ore with acid.
Regarding claim 27 and its dependent claims 28-32, as discussed above for claim 18, the closest teaching of Peng towards using sodium persulfate does not impart a reasonable expectation of success in applying this oxidant to the leaching of lithium from a sedimentary ore with acid.
Regarding claim 35, Xu teaches the method of claim 33, as discussed above, but does not teach or suggest forming reactive oxygen species within the solution. In the prior art, where reactive oxygen species are formed in solutions derived from acidic leaching of lithium from sedimentary ores, they are used to precipitate undesirable impurities such as iron from the leachate (see Xi, [0017], adding hydrogen peroxide, for example). However, this step is performed in the context of leaching processes using a much higher concentration of sulfuric acid than what is claimed in the independent claim 33 (see Xi, [0062], 25-60% sulfuric acid, for example). There is no teaching or suggestion of either:
decreasing the concentration of acid in methods which form reactive species to fall within the claimed range of 0.1-3 M as claimed in claim 33, or
forming reactive oxygen species in Xu’s method, whose acid concentration does fall within the aforementioned range.
Therefore, the claim contains allowable subject matter.
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 ZACHARY J. BAUM whose telephone number is (571)270-0895. The examiner can normally be reached Monday-Friday 8:30-5:00.
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/ZACHARY JOHN BAUM/Examiner, Art Unit 1736
/ANTHONY J ZIMMER/Supervisory Patent Examiner, Art Unit 1736