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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 3/17/2026 has been entered.
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.
Claims 1, 2, and 5-13 are rejected under 35 U.S.C. §103 as being unpatentable over Garforth et al. (EP 2 649 121 B1) in view of Streed et al. (US 3,702,818).
Garforth discloses a process for hydrodepolymerization (hydrocracking) of polymeric waste material comprising providing a feedstock of plastic waste including polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) (¶¶[0013], [0016], [0018], [0020]), introducing the feedstock into a reactor and treating it in the presence of hydrogen (¶[0013]; ¶[0040]–[0042]), and contacting the feedstock with a hydrocracking catalyst comprising a hydrogenation function and an acidic cracking function, wherein hydrogenation metals such as Ni, Co, Mo, Pt, and Pd are supported on inorganic carriers such as alumina, silica-alumina, and zeolites, and the acidic cracking function is provided by these supports (¶[0005]). The hydrocracking is conducted at hydrogen pressures below about 200 bar and temperatures of about 150–400°C (¶[0013], ¶[0042]), followed by separation of gaseous and liquid hydrodepolymerization products and optional recycle of unconverted material (¶[0013]; Figs. 1–2).
Garforth does not explicitly teach:
the hydrogenation catalyst and depolymerization catalyst as separate catalysts combined as a physical mixture
the weight ratio of 100:1 to 1:3
a catalyst-to-feed ratio as claimed
a feed having less than 10 wt.% volatiles
a feed having less than 1 wt.% chlorine
a product having low olefinic or aromatic content as recited
Streed discloses hydrocracking catalysts comprising hydrogenation metals (e.g., Ni, Co, Mo, W, Pt, Pd) combined with acidic cracking components such as zeolites, silica-alumina, and alumina (Streed, col. 3–5), and further teaches that the hydrogenation component may be incorporated into the acidic catalyst by ion exchange, impregnation, or as a physical mixture (Streed, col. 6, lines 50–67).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Garforth by providing the hydrogenation catalyst and the depolymerization (acidic) catalyst as separate catalyst components combined as a physical mixture, as taught by Streed, since Streed explicitly identifies physical mixture as a known and interchangeable configuration for hydrocracking catalysts.
Garforth teaches that the balance between hydrogenation and acidic cracking functions is critical (EP ’121 ¶[0005]). Accordingly, the relative proportion of hydrogenation and acidic catalyst components is a result-effective variable. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have selected a hydrogenation-to-depolymerization catalyst weight ratio within the claimed range of 100:1 to 1:3 as a matter of routine optimization, absent evidence of criticality (In re Aller).
The catalyst-to-feed ratio governs conversion and process severity. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have selected a catalyst-to-feed ratio within the claimed range as a matter of routine optimization to achieve hydrocracking.
Garforth teaches processing plastic waste feedstocks and performing pretreatment steps. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Garforth by employing a feedstock having less than 10 wt.% volatiles, since removal of volatile components (e.g., moisture and light ends) is a routine feed conditioning step in hydroprocessing to improve process stability and catalyst performance.
Garforth teaches dechlorination of the feedstock prior to hydrocracking (¶[0013]). It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Garforth to utilize a feedstock having less than 1 wt.% chlorine as a routine and desirable outcome of the taught dechlorination step to avoid corrosion and catalyst poisoning.
Garforth employs hydrogenation metals under hydrogenation conditions (¶[0005]). It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have operated the process of Garforth under conditions sufficient to produce a product having reduced olefinic content (e.g., bromine number <20) and reduced aromatic proton content, since hydrocracking under hydrogenation conditions inherently saturates olefins and reduces aromaticity.
Claim 4 is rejected under 35 U.S.C. §103 as being unpatentable over the references as
applied to claim 1 above, and further in view of Rana et al. (US 9,919,293 B1).
Garforth does not explicitly disclose a pore volume.
Rana teaches hydrocracking catalyst supports having pore volumes of about 0.25–1.5 mL/g
(see abstract).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the catalyst of Garforth to have a pore volume within the claimed range because pore volume is a known parameter affecting catalyst performance.
Claim 15 is rejected under 35 U.S.C. §103 as being unpatentable over the references as applied to claim 1 above, and further in view of Narayanaswamy et al. (US 2018/0002609 A1).
Garforth teaches hydrocarbon products suitable as downstream feedstocks (EP ’121 ¶[0009]) but does not explicitly teach steam cracking.
Narayanaswamy teaches introducing hydrocarbon streams into a steam cracker to produce olefins.
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have further modified the process of Garforth to pass the hydrodepolymerization product into a steam cracker to produce olefins, since hydrocracked hydrocarbons are conventional feedstocks for steam cracking.
Response to Arguments
Applicant argues that the cited references do not teach or suggest (i) a hydrocracking catalyst that is a physical mixture of a hydrogenation catalyst and a depolymerization catalyst, and (ii) a weight ratio of 100:1 to 1:3 between these components, and therefore no prima facie case of obviousness has been established. These arguments are not persuasive. With respect to the physical mixture limitation, while Garforth primarily teaches hydrocracking catalysts in which the hydrogenation component is supported on an acidic carrier, Garforth nevertheless clearly teaches the use of catalysts providing both hydrogenation and acidic cracking functions in hydrocracking of polymeric materials (¶[0005]). Streed, which is likewise directed to hydrocracking catalysts, explicitly teaches that the hydrogenation component may be introduced into the acidic catalyst “by ion exchange, impregnation or as a physical mixture” (Streed, col. 6, lines 1–8), thereby establishing that physical mixture is a known and interchangeable method of combining hydrogenation and cracking functions in hydrocracking systems. Accordingly, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the catalyst system of Garforth to provide the hydrogenation and depolymerization functions as a physical mixture, as taught by Streed.
Regarding the claimed weight ratio of 100:1 to 1:3, Garforth teaches that the balance between hydrogenation and acidic functions is critical to catalyst performance (¶[0005]), thereby identifying the relative proportion of these functions as a result-effective variable. Once the catalyst is provided as a physical mixture, the relative amounts of the hydrogenation and acidic components would have been routinely adjusted to achieve desired hydrocracking activity, product distribution, and coke suppression. Applicant has not provided evidence of criticality or unexpected results associated with the claimed range. Accordingly, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have selected a hydrogenation-to-depolymerization catalyst weight ratio within the claimed range as a matter of routine optimization. See In re Aller, 220 F.2d 454 (CCPA 1955).
Applicant’s assertion that no prima facie case has been established because the references do not individually disclose all claim limitations is unpersuasive, as a proper obviousness rejection is based on the combined teachings of the references rather than any single reference alone. See In re Keller, 642 F.2d 413 (CCPA 1981). Here, Garforth teaches the claimed hydrodepolymerization process and catalyst functionality, while Streed teaches the physical mixture configuration, and their combination renders the claimed invention obvious.
Accordingly, the arguments are not persuasive and the rejection is maintained.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TAM M NGUYEN whose telephone number is (571)272-1452. The examiner can normally be reached Mon - Frid.
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/TAM M NGUYEN/Primary Examiner, Art Unit 1771
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