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 .
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.
Priority
3. This application is a 371 of PCT/EP2022/069672 07/13/2022.
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application EP 21191768.7 08/17/2021 filed on 01/11/24.
Information Disclosure Statement
The information disclosure statement (IDS), filed on 01/11/24 has been considered. Please refer to Applicant's copy of the 1449 submitted herewith.
Claim Objections
Claims 1-15 are objected to because of the following informalities:
In claim 1, applicants are suggested to change “course” in line 21 to “coarse” to represent particulate.
Claims 2-15 depends from objected claim 1.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 10 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, claim 10 recites the broad recitation “flow-through mode,” and the claim also recites “preferably in Soxhlet extractor” which is the narrower statement of the range/limitation. The claim(s) are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims.
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.
Claims 1-5, 7, 9-15 are rejected under 35 U.S.C. 103 as being unpatentable over Ibrahim (Q. Ibrahim et al, Prehydrolysis and organosolv delignification process for the recovery of hemicellulose and lignin from beech wood, Bioresource Technology Reports. 11, 2020, 100506, pages 11-11) in view of Ouyang (X. Ouyang et al, Coupling organosolv fractionation and reductive depolymerization of woody biomass in a two-step catalytic process, Green Chemistry 20, 2018, 2308-2319) and Kirci (H. Kieci, et al, Production of dissolving grade pulp from poplar wood by ethanol-water process, Turkish Journal of Agriculture and Forestry, 26, 2002, 239-245).
Regarding claims 1-2, 4, 7, 13-15, Ibrahim discloses a method of producing dissolving cellulose, wherein the methos comprises providing beech wood chips particles of approximately 2.5-3.5 mm as a particulate lignocellulosic biomass feedstock (read on course or coarse) and providing an aqueous (water) in presence of acid H2SO4 (read on acid catalyst) as first solvent for prehydrolysis, and contacting the beech wood with the aqueous first solvent under elevated-temperature and implicit pressure conditions effective to remove hemicellulose, wherein recovery of 85.8 wt.% of the original xylan occurs during the prehydrolysis stage (page 2 para 4-5, page 3 section 2.2.1), wherein the dissolving cellulose is free of metallic catalyst and comprising hemicellulose and hemicellulose derivatives (conclusion, entire Ibrahim). Ibrahim thus teaches removal of hemicellulose from the lignocellulosic biomass into a first-stage hemicellulose-containing stream. Ibrahim further discloses the prehydrolysis precedes the organosolv delignification and that prehydrolysis enhances subsequent lignin recovery (page 2, para 4). Thus, Ibrahim teaches or suggests the claimed sequential relationship wherein hemicellulose is removed before the subsequent removal of lignin. Ibrahim teaches providing a second solvent comprising a low-boiling liquid organic compound, specifically, Ibrahim teaches subsequent organosolv delignification using 50 wt.% aqueous ethanol, wherein the delignification is 82.7 wt%, wherein contacting the prehydrolyzed biomass with the aqueous ethanol solvent under organosolv conditions, including about 150°C and implicit pressure for 70 minutes, thereby removing lignin from the prehydrolyzed biomass and the overall process as providing separate hemicellulose, lignin and cellulose streams (abstract, page 3, section 2.2.2; fall into claim 1 range of upto 94% or claim 7 range of at least 80%). Ibrahim therefore teaches the claimed sequence of first removing hemicellulose from lignocellulosic biomass using an aqueous treatment and thereafter removing lignin from the resulting biomass using a second solvent comprising ethanol thereby providing a lignin-containing fraction and a cellulose-rich, delignified biomass. Ibrahim does not expressly teach separating the lignin-containing fraction as a lignin oil as required by step F of claim 1.
Ouyang teaches organosolv fractionation of woody lignocellulosic biomass using a low-boiling organic solvent, specifically methanol, in the presence of an acid catalyst, wherein organosolv fractionation produces a lignin oil and cellulose pulp and further teaches separation of the cellulose pulp from the lignin-containing fraction (abstract, experimental).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ the lignin-oil recovery taught by Ouyang in the organosolv delignification process of Ibrahim in order to recover Ibrahim's solubilized lignin fraction as a separately usable lignin-oil product. Ibrahim expressly seeks recovery and valorization of lignin as a separate product stream, and Ouyang teaches a known organosolv technique for obtaining the separated lignin from woody biomass as lignin oil while retaining cellulose pulp. The modification amounts to applying a known lignin-recovery technique to the lignin-containing organosolv stream of a similar woody-biomass fractionation process for its known purpose and would have yielded the predictable result of a separated lignin oil and cellulose-rich pulp. See MPEP §2143.
A person of ordinary skill in the art would have had a reasonable expectation of success because both Ibrahim and Ouyang employ alcohol-based organosolv treatment of woody lignocellulosic biomass to solubilize lignin while retaining a cellulose-rich solid, and Ouyang experimentally demonstrates recovery of lignin oil and cellulose pulp from such fractionation.
Ibrahim in view of Ouyang does not expressly teach bleaching the resulting cellulose pulp to produce dissolving cellulose as required by steps G and H of claim 1.
Kirci discloses production of dissolving-grade cellulose pulp from woody lignocellulosic biomass using an ethanol-water process, e.g. processing pulp in unbleached form before subsequent bleaching and purification to evaluates unbleached, bleached, and alkali-purified pulps and bleaching and purification of the ethanol-water-derived pulp to obtain dissolving-grade pulp, wherein after bleaching and alkali purification, a pulp containing 95.8% a-cellulose, having a viscosity of 677 cm3/g and brightness of 83%, wherein a multistage CEHDED bleaching treatment increasing brightness to approximately 88.5% to concludes that the resulting pulps satisfy dissolving-grade pulp requirements (abstract, results and discussion pages 241-244).
It would have been obvious to one of ordinary skill in the art before the effective filing date to subject the cellulose-rich pulp resulting from the modified lbrahim fractionation process to the bleaching and purification treatment as taught by Kirki.
The rationale to do so would have been motivation provided by Kirki that to do so would help to obtain dissolving-grade cellulose.
Regarding claim 3, Ibrahim discloses claimed sequential fractionation of woody biomass by aqueous removal of hemicellulose followed by organosolv delignification using aqueous ethanol, but does not expressly disclose using one and the same solvent mixture for both operations.
Ouyang discloses organosolv fractionation of woody biomass using methanol and an acid catalyst such as aqueous HCl, e.g. 37 wt% HCl in water (experimental); thus, the reaction medium necessarily comprise water and low boiling methanol, wherein the aqueous water/methanol containing medium is suitable for fractionation/delignification of woody lignocellulosic biomass to provide lignin oil and cellulose pulp (abstract, results and discussion).
It would have been obvious to one with ordinary skill, in the art at the time of invention, to modify Ibrahim by employing Ouyang’s known aqueous water/methanol solvent mixture as the common solvent mixture in Ibrahim’s hemicellulose removal and lignin removal operation, because Ibrahim already teaches water containing treatment followed by aqueous ethanol organosolv treatment for fractionating the same woody biomass, while Ouyang demonstrate that aqueous water containing low boiling alcohol medium is suitable for such biomass fractionation. Such modification represents use of known aqueous alcohol solvent system for its known biomass fractionation function and would have been expected to retain Ibrahim’s separation of hemicellulose and lignin while producing a cellulose rich compound.
Regarding claim 5, Ouyang expressly teaches that after organosolv fractionation produces lignin oil and cellulose pulp, the lignin oil is subjected in a second step to reductive depolymerization in methanol under H, using Pd/C catalyst. Ouyang reports operation at approximately 180°C, 2 h and 30 bar, yielding phenolic monomers (abstract, table 1).
It would have been obvious to one with ordinary skill, in the art at the time of invention, to modify Ibrahim the depolymerization step, as taught by Ouyang
The rationale to do so would have been motivation provided by Ouyang that to do so would help upgrade the lignin oil into valuable lower-molecular-weight phenolic products.
Regarding claim 9, Kirci expressly adapted the organosolv process for batch-type pulping and conducted the pulping in a 15-L laboratory rotary digester (page 240, para 7). Ouyang likewise performs its organosolv fractionation as a finite-time treatment of woody biomass in methanol, e.g., 160°C for two hours (table 1).
It would have been obvious to carry out the organosolv stage of the modified Ibrahim process batch-wise because batch organosolv treatment was a known mode of carrying out the same alcohol-based lignocellulosic pulping operation, as expressly demonstrated by Kirci.
Regarding claim 10, Ouyang expressly teaches fractionation continuous flow process (page 2309, para 3, scheme 1). It has been noted that continuous flow process produces products nonstop without interruption, delivering lower unit costs, higher production rates, and consistent quality.
It would have been obvious to one with ordinary skill, in the art at the time of invention, to modify Ibrahim with the fractionation continuous flow process, as taught by Ouyang to produce products, e.g., cellulose nonstop without interruption, delivering lower unit costs, higher production rates, and consistent quality.
Regarding claim 11, Ouyang expressly teaches the organosolv delignification conditions of about 17 bars (table 1), fall into claimed 30 bars.
It would have been obvious to one with ordinary skill, in the art at the time of invention, to conduct Ibrahim’s organosolv delignification at pressure of about 17 bars, as taught by Ouyang. The rationale to do so would have been motivation provided by of Ouyang that woody lignocellulosic biomass can successfully delignified in a low boiling alcohol solvent at about 17 bars, thereby providing known operating pressure suitable for the same type of organosolv delignification employed by Ibrahim. Selection of Ouyang’s operating pressure for Ibrahim’s organosolv delignification would have been a predictable use of known process conditions for their known purpose, with reasonable expectation of successful delignification.
Regarding claim 12, Ibrahim discloses beech wood chips (section 2.1).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Ibrahim in view of Ouyang and Kirci as applied to claims 1, 5 above, and further in view of Anderson (E. M. Anderson et al., "Flowthrough Reductive Catalytic Fractionation of Biomass," Joule 1 (2017) 613-622).
Ibrahim includes the features of claims 1, 5 above.
Regarding claim 6, Ibrahim does not disclose the reducing catalyst is not contacted with the lignocellulosic biomass feedstock during the method.
However, Anderson discloses a flowthrough reductive catalytic fractionation system in which the biomass bed is physically separated from the catalyst bed, wherein a dual-bed configuration having switchable biomass beds physically separated from the catalyst in a separate reactor, thereby decoupling lignin solvolysis from catalytic hydrogenolysis (page 615). Anderson further identifies facile catalyst separation and recovery as advantages of this arrangement (page 615).
It would have been obvious to perform the modified Ibrahim (Ouyang) lignin-oil depolymerization using Anderson's physically separated catalyst configuration in order to obtain the known benefits expressly identified by Anderson, including independent control of solvolysis and hydrogenolysis and facile catalyst recovery, while preventing contact between the biomass and reducing catalyst. The modification does not change the chemistry relied upon in Ouyang; it spatially separates the known catalytic lignin-upgrading operation from the biomass.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Ibrahim in view of Ouyang and Kirci as applied to claim 1 above, and further in view of Torget (US 5424417).
Ibrahim includes the features of claim 1 above.
Regarding claim 8, Ibrahim does not disclose pressurized CO2 is added to the solvent as an acidic catalyst in step C.
However, Torget discloses aqueous prehydrolysis of lignocellulosic biomass using carbonic acid, and expressly states that carbon dioxide may be injected into the reactor to prepare carbonic acid in situ at approximately 140-240°C with sufficient pressure to maintain water and CO2, in the liquid phase (column 10, lines 32-, column 11, lines -6). Torget further reports that the prehydrolysis removes more than 90% of the xylan directly establishing the effectiveness of the CO2,/carbonic-acid treatment for hemicellulose removal (column 22, lines 56-59).
It would have been obvious to substitute Target's carbonic-acid/pressurized-CO2 catalyst for the sulfuric acid employed in Ibrahim's aqueous prehydrolysis because both acids are used for the same purpose-acid-promoted aqueous prehydrolysis and removal of hemicellulose from lignocellulosic biomass. Target expressly demonstrates successful hemicellulose removal using the proposed substitute. A person of ordinary skill therefore would have had a reasonable expectation of success.
Conclusion
References AMIRI et al., "Fractionation of lignocellulosic biomass to produce uncondensed aldehyde-stabilized lignin", NATURE 1 PROTOCOLS, March 2019, 14: 921-954, LIU et al., "The effect of non-structural components and lignin on hemicellulose extraction", Bioresource Technology, 2 2016, 214: 755-760, RENDERS et al., "Synergetic Effects of Alcohol/Water Mixing on the Catalytic Reductive Fractionation of Poplar 3 Wood", ACS Sustainable Chemistry & Engineering, 2016, 4: 6894-6904, STOFFEL et al., "Hemicellulose extraction from slash pine sawdust by stream explosion with sulfuric acid", Biomass 4 and Bioenergy, 2017, 107: 93-101 and Kleinert (US 5424417) were cumulative in nature to the above rejection and thus not set forth.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KUMAR R BHUSHAN whose telephone number is (313)446-4807. The examiner can normally be reached 9.00 AM to 5.50 PM (EST).
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/KUMAR R BHUSHAN/Primary Examiner, Art Unit 1766
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