DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-3, 5-7, 9, 10, 12, 14-16, 18-25, 28, 29, 55 and 56 are pending as amended on 4/1/2024.
Drawings
The drawings are objected to because the resolution or size of the text in some of the figures is too low or too small to be legible. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
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.
Claims 9, 10, 18, 19 and 24 are 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.
Claim 9 recites subjecting… to relatively higher temperatures. Because the claim does not recite any baseline temperature for comparison, it is not clear what is meant by “relatively higher,” thereby rendering the scope of the claim unclear.
Claim 10 recites a process wherein dissolution comprises “agitation” and/or “low shear agitation.” It is not clear how a dissolution could comprise both “agitation” and “low shear agitation,” as one is merely a narrower embodiment of the other.
Claim 18 recites maximum values of PHA, but does not recite the values as alternatives. It is therefore unclear what maximum value of PHA is encompassed by the claim.
Claim 19 recites pore size ranges, but does not recite the ranges as alternatives, and therefore it is unclear which range must be met. It is also unclear what is meant by “and overlapping ranges thereof.”
In claim 24, it is unclear whether “the internal filter” refers to a filter which is necessarily present to carry out the filtration of residual solvent vapor (as recited in claim 23), or, whether “the internal filter” refers to the filter in the dissolution vessel used for separation of PHA/solvent from biomass (as recited in claim 14).
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 3 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends. Claim 3 depends from claim 1 and requires the external solvent to be halogenated or non-halogenated. However, any solvent must be either halogenated or non-halogenated, and therefore, the scope of claim 3 is the same as (does not further limit) the scope of claim 1. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
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.
Claim(s) 1-3, 5, 6, 7, 9, 10, 12, 18, 25 and 55 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van Walsem (US 20100197885).
As to claims 1-3, 7, 9, 10 and 55, Van Walsem discloses a process wherein a biomass containing PHA [0035] in the form of a slurry [0036] is contacted with a solvent system [0044] which includes a solvent for PHA [0045-7]. The mixture is heated [0067] and agitated [0068-9] to allow the PHA to be removed from the biomass [0067] and to generate a PHA-rich solvent phase [0071] and a PHA-reduced biomass [0072]. Van Walsem does not explicitly teach “a dissolution vessel” as recited in step “a.” However, it would have been obvious to the person having ordinary skill in the art to have performed a process of heating and agitating a mixture, as taught by Van Walsem, in a vessel in order to contain the materials and perform the steps of heating and agitating in a conventional manner. Therefore, Van Walsem suggests a process which comprises steps according to instant “a” and “b” recited in claim 1.
Van Walsem discloses separation of the PHA phase (PHA-rich solvent) from the residual biomass phase (PHA-reduced biomass) [0073], using centrifugation [0075], which corresponds to instant step (c).
Van Walsem further discloses adding a precipitant to the PHA phase to form a mixture [0080] to generate precipitated PHA [0082], meeting instant step (d), and separating precipitated PHA from the liquid [0083-4], meeting instant step (e). The PHA is then dried [0085], meeting instant (f), and pelletized [0085], meeting instant (g) (and meeting instant claim 55).
As to claims 5 and 6, the recited solvents are found in [0050-53] of Van Walsem, and butyl acetate, as recited in instant claim 6, is recited in [0051]. Butyl acetate is further exemplified as the solvent in [0111].
As to claim 12, Van Walsem discloses agitation (dissolution) for less than about three hours [0070], which meets a range of 0 to 5 hours as recited in claim 12.
As to claim 18, Van Walsem fails to teach the PHA content which remains in the PHA-reduced biomass. However, Van Walsem teaches agitation of the solvent system and slurry mixture until the PHA phase has a desired PHA solids content [0070], and teaches decreasing the viscosity of the PHA phase results in improved separation of the phases [0073]. The goal of the process taught by Van Walsem is a reduction in the amount of PHA remaining in the residual biomass [0003] (because PHA is the desired product to be extracted from the biomass). It would have been obvious to the person having ordinary skill in the art, therefore, to have reduced the amount of PHA remaining in the biomass when carrying out the process in Van Walsem in order to increase the yield of the desired product (PHA), including reducing the PHA remaining in the biomass to an amount within the claimed range.
As to claim 25, Van Walsem discloses that at least 97 vol% of the initially used solvent is recovered for re-use [0088]. Van Walsem also teaches distilling the solvent system/precipitant mixture so that the components (solvent and precipitant) can be re-used [0105]. It would have been obvious to the person having ordinary skill in the art, therefore, to have re-used Van Walsem’s solvent in any part of the process in which solvent was initially used, including, e.g., the dissolution vessel, in order to reduce waste and environmental impact.
Claim(s) 14-16, 19-24 and 29 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van Walsem (US 20100197885) in view of Narasimhan et al (US 2005/0287653).
As to claims 14-16, Van Walsem discloses a process wherein a biomass containing PHA [0035] in the form of a slurry [0036] is contacted with a solvent system [0044] which includes a solvent for PHA [0045-7]. The mixture is heated [0067] and agitated [0068-9] to allow the PHA to be removed from the biomass [0067] and to generate a PHA-rich solvent phase [0071] and a PHA-reduced biomass [0072], corresponding to instant step (b) recited in claim 1. Van Walsem discloses separation of the PHA phase (PHA-rich solvent) from the residual biomass phase (PHA-reduced biomass) [0073], using centrifugation [0075], which corresponds to instant step (c).
Van Walsem does not explicitly teach “a dissolution vessel” as recited in step “a” which comprises an internal filter, as recited in claim 14.
Like Van Walsem, Narasimhan discloses a process for extracting PHA from biomass [0017] by stirring [0048] and heating [0051-4] the biomass in a solvent [0044], and then separating biomass from PHA-enriched liquor [0055]. Narasimhan discloses that methods of separation include centrifugation, but that a preferred method of filtration is high temperature filtration before the PHA liquor cools significantly, and that preferred filtration devices include Nutsche filters with mixing, heating and washing capabilities [0056]. Considering Narasimhan’s disclosure, the person having ordinary skill in the art would have been motivated to utilize a Nutsche filter to perform a solvent extraction of PHA from biomass in order to carry out the steps of mixing, heating and filtering the biomass, PHA and solvent in a single vessel, and in order to carry out the filtration before the PHA liquor cools. It would have been obvious to the person having ordinary skill in the art, therefore, to have carried out Van Walsem’s steps of contacting biomass slurry with solvent, heating and agitating, followed by separation of PHA-rich solvent from residual biomass, in a Nutsche filter (as taught by Narasimhan), thereby arriving at a process comprising steps (a) through (c) as recited in claims 14-16.
Van Walsem further discloses adding a precipitant to the PHA phase to form a mixture [0080] to generate precipitated PHA [0082], meeting instant step (d), and separating precipitated PHA from the liquid [0083-4], meeting instant step (e). The PHA is then dried [0085], meeting instant (f), and pelletized [0085], meeting instant (g).
As to claim 19, modified Van Walsem suggests a method according to claim 16, as set forth above, wherein PHA is extracted in solvent and separated from biomass in a Nutsche style filter. One having ordinary skill in the art would have recognized that the pore size of a filter is a result effective variable - as filter pore size increases, the content of solid impurities which are able to pass through the filter with the desired solution increases. As pore size decreases, the rate at which desired solution passes through the filter decreases. It would have been obvious to the person having ordinary skill in the art, therefore, to have selected any appropriate filter pore size in order to achieve a desired balance between purity (smaller pore size) and filtration efficiency (larger pore size), including a pore size within the presently claimed range.
As to claims 20-22, modified Van Walsem suggests a method according to claim 16, as set forth above. Van Walsem further teaches that the components of the solvent system can be stripped from the remaining biomass phase using standard techniques such as in vacuum drier [0090], corresponding to the step of drying the PHA-reduced biomass as recited in claims 20 and 21. The solvent contained in the biomass can be recovered, such as by “solvent condensation” [0090], corresponding to a step wherein solvent vapor released from the biomass during drying is trapped, as recited in claim 22.
As to claim 23, modified Van Walsem suggests a method according to claim 22, as set forth above. Van Walsem discloses that at least 97 vol% of the initially used solvent is recovered for re-use [0088]. Van Walsem also teaches distilling the solvent system/precipitant mixture so that the components (solvent and precipitant) can be re-used [0105]. It would have been obvious to the person having ordinary skill in the art, therefore, to have re-used Van Walsem’s solvent in any part of the process in which solvent was initially used in order to reduce waste and environmental impact. Van Walsem fails to specifically teach filtration of the trapped residual solvent vapor, as recited in claim 23.
However, Van Walsem teaches quantifying polymer content and impurity content [0094], and teaches various methods which can be used to facilitate the formation of a relatively pure isolated, extracted PHA (purity of at least 99.5% or 99.9%) [0096, 97]. When recycling/reusing recovered solvent to steps of a process in which the solvent was initially used, the person having ordinary skill in the art would have been motivated to purify the solvent utilizing any conventional means known in the art in order to minimize introduction of, and accumulation of, impurities in the product as the process is repeated using recycled solvent. It would have been obvious to the person having ordinary skill in the art, therefore, to have applied any common purification technique to the recovered solvent vapor in the process suggested by modified Van Walsem prior to reusing the components, including filtration, as recited in claim 23.
As to claim 24, modified Van Walsem suggests a method according to claim 23, as set forth above. Van Walsem fails to teach an activated carbon filter.
Narasimhan teaches the use of fresh solvent for the washing of PHA because it is less costly than using substances such as activated carbon [0066]. Considering Narasimhan’s disclosure, one having ordinary skill in the art would have recognized activated carbon as being a suitable filtration material for removing impurities from solvent used in a PHA extraction process. Even if use of fresh solvent is less costly than using recovered solvent purified by activated carbon (as taught by Narasimhan), the person having ordinary skill in the art would have been motivated to recover, purify, and reuse solvent where reduction of environmental impact is of higher priority than process cost. It would have been obvious to the person having ordinary skill in the art, therefore, to have utilized any suitable known filtration material in the process of modified Van Walsem in order to reduce accumulation of impurities when reusing recovered solvent, including activated carbon.
As to claim 29, modified Van Walsem suggests a method according to claim 20, as set forth above. Van Walsem teaches that the biomass can be dried to recover and/or eliminate residual solvent, and can be reused as a nutrient for fermentation after removing residual solvent [0090]. It would have been obvious to the person having ordinary skill in the art, therefore, to have re-fed the biomass into the fermentation broth to form a slurry, as taught by Van Walsem in [0034], which is subsequently extracted with solvent [0044], thereby arriving at a process as presently recited wherein PHA-reduced biomass is re-fed into the renewable and sustainable process for further extraction of PHA.
Claim(s) 28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van Walsem (US 20100197885) in view of Narasimhan et al (US 2005/0287653), and further in view of Stelte et al (Recent Developments in Biomass pelletization - A review; BioRes. 7(3), 4451-4490 (2012)).
The rejection of claim 20 over Van Walsem in view of Narasimhan is incorporated here by reference.
As to claim 28, modified Van Walsem suggests a method according to claim 20, as set forth above. Van Walsem teaches that the biomass can be dried to recover and/or eliminate residual solvent, and can be reused as a nutrient for fermentation after removing residual solvent [0090]. Van Walsem fails to teach milling and/or pelleting of the dried/recovered biomass.
Stelte teaches that attempts to overcome the poor handling properties of biomass (low bulk density, inhomogeneous) have resulted in an increase in interest in biomass densification, such as pelletization (abstract). Compaction of biomass into pellets is an old process that has been known for more than 130 years (p 4453, first full paragraph) and pelletization offers density increase, and homogenous shape and structure (p 4452, second paragraph). In view of Stelte’s disclosure, it would have been obvious to the person having ordinary skill in the art to have pelletized the dried recovered biomass in the process of modified Van Walsem in order to provide the biomass in a more convenient form (increased density and homogeneity) for subsequent use.
Claim(s) 56 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van Walsem (US 20100197885) in view Herrema (US 2020/0115724).
The rejection of claim 1 over Van Walsem is incorporated here by reference.
Van Walsem fails to teach that the biomass is derived from methanotrophic microorganisms. However, Herrema teaches a methanotrophic microorganism that is capable of generating PHA at high efficiency levels, resulting in increased PHA yield [0010, 0028-29]. It would have been obvious to the person having ordinary skill in the art, therefore, to have utilized a methanotrophic microorganism, as taught by Herrema, to derive the biomass in Van Walsem, in order to increase PHA yield at high efficiency levels.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL KAHN whose telephone number is (571)270-7346. The examiner can normally be reached Monday to Friday, 8-5.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Randy Gulakowski can be reached at 571-272-1302. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/RACHEL KAHN/ Primary Examiner, Art Unit 1766
Prosecution Insights