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.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 13 August 2026 has been entered.
Claim Amendments
Applicant’s amendment to claim 36 is acknowledged and has been considered for this action. It is noted, however, that the claim status identifier on this claim as submitted with the reply filed 13 August 2026 is incorrect, as it lists only “Previously Presented” when in fact additional limitations have been added to the claim.
Information Disclosure Statement
The Information Disclosure Statement filed on 13 August 2026 has been received and considered by the Examiner.
Claim Interpretation
Claim 36 recites the limitation “wherein the polyolefin (PO)-containing waste plastic stream is obtained from a stream of mixed plastic waste that has not been subjected to solvolysis.” This limitation is interpreted as requiring that the PO-containing stream be separated from a stream of mixed waste plastic before the stream of mixed waste plastic is subjected to solvolysis, if it is subjected to solvolysis at all.
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.
Claims 36-41 are rejected under 35 U.S.C. 103 as being unpatentable over de Broqueville (US 5,288,934) in view of Muller (US 2012/0083542 A1) and Gallagher et al. (US 5,710,315).
Regarding claim 36, de Broqueville teaches a method for processing waste plastic (col. 2, lines 52-60) comprising recovering a polyolefin-containing waste plastic stream (col. 4, line 3-5 and col. 6 lines 18-24) and a solvolysis coproduct stream from a solvolysis facility (non-crackable residues of PET methanolysis; col. 7, lines 27-30), wherein the PO-containing waste plastic stream is obtained from a stream of mixed waste plastic that has not been subjected to solvolysis (only the downstream PET fraction is subjected to hydrolysis or methanolysis; col. 7, l. 27), and wherein the solvolysis co-product stream is a methanolysis co-product stream (non-crackable residues of PET methanolysis; col. 7, lines 27-30).
De Broqueville does not teach introducing the polyolefin containing waste plastic stream and the solvolysis coproduct stream from a solvolysis facility into any of the facilities recited in the claim, nor does de Broqueville teach the specific contents of the solvolysis product streams as recited in the claim.
However, Muller also teaches a process for handling mixed waste plastic (abstract and [0014]-[0016]) that generates a PO-containing stream (blue arrow in amended Fig. 3, below) and a solvolysis co-product stream from the solvolysis of PET in a solvolysis facility (red arrow). Muller further teaches in Fig. 3 that these two streams may be routed for energy use, and such a process must be facilitated by introducing these streams to an energy generation/energy production facility.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to route the PO-containing stream and the solvolysis co-product stream of de Broqueville to an energy generation/production facility, as taught by Muller. One of ordinary skill in the art would have been motivated to do so in order to extract value from these by sale of the energy generated therefrom, as taught by Muller (Fig. 3).
Muller also teaches the solvolysis coproduct stream being obtained by subjecting a PET-containing waste stream plastic to solvolysis (the first step is based on treating organic waste components by means of solvolysis, such that subsequently they are present in at least one liquid phase; [0022], [0083]-[0084] discuss applying this to PET) to produce a raw materials stream that would comprise the principal glycols (Dioles [sic] and other raw materials, Fig. 3) and a solvolysis co-product stream (the stream that is not diols and other raw materials in Fig. 3; or Not sellable or not separable components, Fig. 2). Muller further teaches that the stream comprising diols and other raw materials is obtained by vacuum distillation separation of the volatile organic compounds following solvolysis (Fig. 2).
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Muller does not specifically teach the production of separate principal glycol and principal terephthalyl streams.
However, Gallagher teaches that methanolysis is effective at depolymerizing polyesters (column 1, line46-48 and column 2, paragraph 2) in mixed waste streams (column 2, lines 43-49), and that the vapor stream product obtained following methanolysis can be further separated into a principal glycol stream (ethylene glycol) and a principal terephthalyl stream (DMT, dimethylterephthalate; col. 8, lines 65-67).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to subject the PET-containing waste stream to methanolysis, as taught by de Broqueville, to generate a principal terephthalyl stream, a principal glycol stream and a solvolysis coproduct stream comprised of non-salable products, as taught by Muller and Gallagher. One of ordinary skill in the art would have been motivated to do so because Gallagher teaches that methanolysis generating these products is an effective method to depolymerize polyesters, which is the function of the solvolysis in the methods of de Broqueville (col. 7, lines 25-31) and Muller ([0083] shows the depolymerization of a polyester), and because Gallagher teaches that the products so obtained are volatile organics that could be recovered and separated into materials that can be reused, which is a goal of Muller and de Broqueville (col. 7, line 30-31).
Regarding claim 37, modified de Broqueville teaches the method of claim 36 where Muller teaches the PO-containing stream and the solvolysis coproduct stream are introduced into an energy generation/energy production facility separately (Fig 3, copied and annotated above shows separate streams directed to energy use).
Regarding claim 38, modified de Broqueville teaches the method of claim 36, and de Broqueville further discloses the catalytic cracking at 450 °C; column 9 lines 8-12) of a combined stream resulting from this process (column 8, lines 1-5), suggesting that streams can be combined before being subjected to a common treatment.
Therefore, it would have been obvious to one of ordinary skill in the art to perform the method of Muller where the PO-containing stream and the solvolysis co-product stream are combined before further use, as taught by de Broqueville, and then introduced to an energy production facility, as taught by Muller. One of ordinary skill in the art would have been motivated to so because combining them would allow them to be transported together, thereby increasing efficiency and reducing the need for multiple routes and inlets to the energy production apparatus.
Regarding claim 39, modified de Broqueville teaches the method of claim 38 and de Broqueville also teaches that their entire process, which would include the combining of streams (column 8, lines 1-5) can be made continuous (column 8, lines 19-24).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the streams of claim 38 in a continuous manner, as taught by de Broqueville. One of ordinary skill in the art would have been motivated to so because de Broqueville teaches that the processes can be made entirely continuous and because it would allow them to use the PO-containing stream as it is produced continuously.
Furthermore, it is noted that the courts have held that continuous operations are obvious in light of a batch process disclosed in the prior art. In re Dilnot, 319 F.2d 188, 138 USPQ 248 (CCPA 1963). See MPEP 2144.04(V).E.
Regarding claim 40, modified de Broqueville teaches the method of claim 38 but does not explicitly teach the weight percents and ratios instantly claimed.
However, it would have been obvious to one of ordinary skill in the art to optimize the weight percent of the PO-containing stream in the combined stream and the ratio of a PO-containing stream to the solvolysis coproduct stream by routine optimization. One of ordinary skill in the art would have been motivated to do so in order to maximize the use of the waste plastic material based upon the composition of the waste plastic feedstock supplied to the recycling facility.
Regarding claim 41, the instant specification ([0178]) defines the term “heavy organic solvolysis coproduct” as a solvolysis coproduct with a boiling point greater than the boiling point of the principal terephthalyl product of the solvolysis facility and the term “light organic solvolysis coproduct” as a solvolysis coproduct with a boiling point lower than the boiling point of the principal terephthalyl product of the solvolysis facility. For the method of modified de Broqueville, Gallagher teaches methanol as the solvolysis solvent for waste streams that contain PET, which will generate dimethylterephthalate (DMT, b.p. 288 °C) as the principal terephthalyl solvolysis product (Gallagher, col. 8, lines 60-67).
Modified de Broqueville teaches the process of claim 36, but is silent with respect to the weight percent of a heavy organic solvolysis coproduct and a light organic solvolysis coproduct, and to the concentration of products in the solvolysis co-product stream in general.
However, the ratios of the weight of the heavy organic solvolysis coproduct and the light organic solvolysis co-products to the weight of the whole solvolysis coproduct stream is expected to be a function of the composition of the plastic feed being supplied to the solvolysis facility.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention to vary by routine experimentation the feed supply to the solvolysis facility based upon the availability of different waste plastics, thereby arriving at a solvolysis co-product stream comprising at least 5 and not more than 60 weight percent of a light organic solvolysis co-product or one comprising at least 50 weight percent of a heavy organic co-product. One of ordinary skill would have been motivated to do so in order to recycle all varied waste plastics that are available.
Generally, differences in concentration will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." See MPEP 2144.05 and In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Claims 42 and 44 are rejected under 35 U.S.C. 103 as being unpatentable over de Broqueville (US 5,288,934) in view of Muller (US 2012/0083542 A1) and Gallagher et al. (US 5,710,315), as applied to claim 36, and further in view of Bergmann et al. (US 2012/0266532 A1) and Smith et al. (US 3,719,749).
Regarding claim 42, modified de Broqueville teaches the process of claim 36, but is silent with respect to POX gasification.
However, Bergmann teaches method largely similar to the methods of de Broqueville and Muller for the treatment of waste plastics (abstract and Fig. 2), and also teaches that organic components can be converted to synthesis gas ([0001]). Bergman does not specify that this gasification take place in a partial oxidation gasification facility.
However, Smith teaches that hydrocarbons can be converted to syngas (H2, CO and CO2) by a solid-fed gasifier in a partial oxidation gasification reaction, which necessarily takes place in a POX gasification facility (column 10, lines 26-33).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to introduce the PO-containing stream and the solvolysis coproduct stream of modified de Broqueville into a POX gasification facility with a solid-fed gasifier. One of ordinary skill in the art would have been motivated to do so because Bergman teaches that organic components of the process, which the PO-containing stream and the solvolysis coproduct stream both are, are appropriate for synthesizing syngas, and Smith teaches a method to do so via partial oxidation gasification with a solid-fed gasifier.
Regarding claim 44, modified de Broqueville teaches the method of claim 36 where the streams are introduced to an energy production facility, but does not teach introducing the streams to at least two of (i) through (iii).
However, Bergmann teaches method largely similar to the methods of de Broqueville and Muller for the treatment of waste plastics (abstract and Fig. 2), and also teaches that organic components can be converted to synthesis gas ([0001]). Bergman does not specify that this gasification take place in a partial oxidation gasification facility. However, Smith teaches that hydrocarbons can be converted to syngas (H2, CO and CO2) in a partial oxidation gasification reaction, which necessarily takes place in a POX gasification facility (column 10, lines 26-33).
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention to introduce the streams to an energy production facility and a POX gasification facility in order to generate syngas. One of ordinary skill would have found it obvious to do so because each element was known in the prior art and introducing the streams to each type of facility would have had the predictable result of producing both energy and syngas from the waste plastic. MPEP 2143(A).
Claim 43 is rejected under 35 U.S.C. 103 as being unpatentable over de Broqueville (US 5,288,934) in view of Muller (US 2012/0083542 A1) and Gallagher et al. (US 5,710,315), as applied to claim 36, and further in view of Bergmann et al. (US 2012/0266532 A1) and Butler et al. (Waste Biomass Valor (2011) 2:227–255).
Regarding claim 43, modified de Broqueville teaches the process of claim 36, but does not teach introducing the streams to a pyrolysis facility. However, Butler teaches the pyrolysis of a polyolefin-containing stream (title) derived from waste plastic to form a recycle content pyrolysis gas (gaseous olefins, Fig. 6) and a recycle content pyrolysis oil (liquid/wax, Fig. 6). Bergman further teaches that a solvolysis coproduct stream can be treated to remove heteroatoms ([0129]), which therefore yields a hydrocarbon that does not contain undesirable elements and would therefore also be suitable for pyrolysis, as taught by Butler (p. 230, column 1, paragraph 1).
Therefore, it would have been obvious to one ordinary skill in the art before the effective filing date of the claimed invention to modify the method of de Broqueville and to route the PO-containing stream and a solvolysis coproduct stream to a pyrolysis facility and to pyrolyze the streams to form a recycle content pyrolysis gas and a recycle content pyrolysis oil, as taught by Butler. One of ordinary skill in the art would have been motivated to do so because Bergman teaches that both streams can be stripped of heteroatoms, which makes them each suitable to the same pyrolysis that Butler teaches is appropriate for polyolefins.
Response to Arguments
Applicant’s arguments, see pages 4-5 of the reply filed 13 August 2026, with respect to the rejection(s) of claims 36-44 under 35 USC § 103 have been fully considered and are persuasive: neither Muller nor Gallagher teach the separation of a PO-containing stream from a mixed waste plastic steam before that mixed steam is subjected to solvolysis. Therefore, the prior rejections have been withdrawn. However, upon further consideration, a new grounds of rejection is made in view of de Broqueville, as analyzed above.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nicholas A Piro whose telephone number is (571)272-6344. The examiner can normally be reached Mon-Fri, 8:00 am-5:00 pm.
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/NICHOLAS A. PIRO/Assistant Examiner, Art Unit 1738
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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