Detailed Actions
The communications received 12/17/2025 have been filed and considered by the Examiner. Claims 15-28 are pending.
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 .
Examiner’s Note
The phrase “the processed aqueous slurry” does not lack antecedent basis as it is understood that the aqueous slurry that passes through the first precipitation process would be the processed aqueous slurry. However the Examiner notes that there would be a clarity issue should the Applicant decide to use “the processed aqueous slurry” in reference to the resultant aqueous slurry that passes through the second precipitation process.
Claim Rejections - 35 USC § 112
The amendments supplied 12/17/2025 have overcome the rejections applied under 35 USC § 112.
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.
Claim(s) 15-17, 21-22, 24, and 26-27 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wimby et al (US 9,175,438) hereinafter WIM cited by the Applicant in the IDS filed 12/14/2023 as WO 2013/070130 A1.
As for claim 15, WIM teaches a method for separation of lignin from an aqueous slurry containing lignocellulosic biomass material comprising:
providing an aqueous slurry containing lignocellulosic biomass material and having an initial pH level (black liquor understood to be at pH of 13) [col. 2 l. 34-43] to a first precipitation phase [col. 2 l. 37-43; col. 4 l. 4-8];
performing the first precipitation phase in a first precipitation vessel (first tower and storage tower) during a first time duration including adding a first acidifier, wherein a decrease in the pH value of the aqueous slurry from said initial pH level to a first pH level is created, wherein the first pH level is above 11 (a pH drop of 1 from 13 results in 12 and after the first phase the black liquor is at pH 11.5) [col. 2 l. 40-47; col. 8 l. 56- col. 9 l. 5];
feeding the processed aqueous slurry from the first precipitation vessel to a second precipitation vessel [col. 9 l. 4-11];
and performing the second precipitation phase in a second precipitation vessel (second tower) during a second time duration of at least 20 minutes (at least 25 minutes) [col. 11 l. 7-26], said second precipitation phase including adding a second acidifier, wherein a decrease in the first pH value from said first pH level to a second pH level is created, wherein said second pH level is above 9 (the pH is dropped to pH 11.2) [col. 2 l. 47-55; col. 9 l. 11-24].
As for claim 16, WIM teaches claim 15 and further comprising performing the second precipitation phase during a time duration of 20-60 minutes (at least 25 minutes with no benefit past 45 minutes, i.e. 25-45 minutes) [col. 11 l. 7-26].
As for claim 17, WIM teaches claim 15, the first precipitation phase is performed during a time duration of at least 10 seconds (at least 25 minutes) [col. 8 l. 25-27].
As for claim 21, WIM teaches claim 15, and the second pH level is above 10 (at 11.2 pH) see claim 15.
As for claim 22, WIM teaches claim 15, and the first pH level is between 11-12 (at 11.5) [see claim 15].
As for claim 24, WIM teaches claim 15, and wherein at least one of the first or second acidifier comprises acidifying gas [col. 3 l. 7-17].
As for claim 26, this is understood to substantially be the method of claim 15 except for the inclusion of the injector which WIM teaches (the device used to charge the black liquor with the acidifying gas in a manner in which the gas is running counter current to the liquor, i.e. the gas is input at pressure i.e. injected) [col. 3 l. 52-60; see claim 15].
As for claim 27, this is understood to be the system that is used to carry out the method of claim 26 [see claim 15] and therefore is taught by WIM.
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.
Claim(s) 18-20, 25 and 28 is/are rejected under 35 U.S.C. 103 as being unpatentable over WIM.
As for claim 18, WIM teaches claim 15, it is understood that at least 10 % of the lignin is precipitated (at least 10 % which overlaps the claimed range, it is understood that at least some more precipitation would occur due to storage) [col. 2 l. 37-42].
In accordance with the MPEP, ‘ 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)’ therefore the overlapping range is obvious [see e.g. MPEP 2144.05(I)].
As for claims 19-20, WIM teaches claim 15, further comprising performing the first precipitation phase in a first precipitation vessel during a first time duration including adding a first acidifier (the acid adding is done in the first carbonizing tower and the storage in the storage vessel) to create a first decrease in pH value to a first pH above 11 (at 11.5 pH) [col. 2 l. 40-47; col. 8 l. 7-27; col. 8 l. 56-col. 9 l. 5], it is understood that at least 15 % and at least 20 % of the lignin is precipitated because during the second phase more than 20 % of the total lignin content is additionally precipitated and it is understood that after the first and second phase a total of 50-80 % is preferably precipitated, therefore from the first phase (including the storage tank phase) at least 30% precipitation could occur to reach a lower limit of 50 % total precipitation when the second phase does only a lower limit additional removal of 20% [col. 2 l. 48-66].
In accordance with the MPEP, ‘ 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)’ therefore the overlapping range is obvious [see e.g. MPEP 2144.05(I)].
As for claim 25, WIM teaches claim 15, and while it does not teach a further precipitation phase including the addition of a third acidifier, it does teach that there can be a limit as to how much residual black liquor can remain due to capacity of the recovery boiler [col. 11 l. 32-47], therefore to further drive down the amounts of residual black liquor a third phase could be added in order to decrease the amount of residual black liquor being sent to the recovery boiler [col. 10 l. 59 – col. 11 l. 35].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have added an additional precipitation phase down-stream the second precipitation phase as a means of reducing the overall residual black liquor sent to an otherwise overloaded recovery boiler.
As for claim 28, WIM teaches claim 15 and further that the first pH level is between 11-12 (as it goes down to 12 and results in 11.5) [col. 2 l. 40-47; col. 8 l.56-col. 9 l. 5] and the second pH level is between 9-11 (as the pH level drops to 11.2 which is close to 11) [col. 2 l. 47-55; col. 9 l. 11-24].
The Examiner notes that the MPEP teaches “Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)” [MPEP 2144.05(I)].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have dropped to 11 from 11.2 as this is a merely close value which the MPEP teaches is prima facie obvious.
Claim(s) 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over WIM in view of HUAMIN (CN104963231A refer to the supplied English translation) hereinafter HUA.
As for claim 23, WIM teaches claim 15, and further comprising adding a second acidifier that at points would cause at least some agitation (it is understood that the gaseous addition done in a counter current manner is substantially agitating) but does not teach it being stirred and deposited continuously.
HUA teaches a method of precipitating elements in a black liquor using acidification with gas [5] in which the gas is added during continuous stirring of the vessel during the step [12; 15], this manner of incorporating the gas with continuous stirring is understood to contribute to the advantages of the invention such as improved yield, purity, and in a manner that is simple, easy, and economical.
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have added the gas continuously while the vessel is being stirred in order to achieve a resultant yield, purity, and in a manner that is simple, easy and economical.
Response to Arguments
Applicant's arguments filed 12/17/2025 have been fully considered but they are not persuasive.
Applicant argues that WIM fails to teach the second precipitation phase as WIM teaches that the second precipitation vessel is merely a storage vessel.
Respectfully the Examiner disagrees that this is an issue.
Fundamentally, all of the vessels utilized in the process will on some level be used to store the aqueous slurry post treatment during a precipitation process. As currently claimed, all that is required is that the aqueous slurry undergo the requisite pH changes in two separate vessels which WIM teaches. The pH changes are understood to be the driving force of the precipitation process and therefore where WIM stores the aqueous slurry under a pH change (such as during its second precipitation phase) it is by default undergoing a precipitation and therefore rendering the storage vessel a second precipitation vessel. For this reason the arguments are not convincing.
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 Elisa Vera whose telephone number is (571)270-7414. The examiner can normally be reached M-F 8 - 4:30.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Abbas Rashid can be reached at 571-270-7457. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/E.V./Examiner, Art Unit 1748
/Abbas Rashid/Supervisory Patent Examiner, Art Unit 1748