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 .
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 1-7, 9 and 11-14 and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Bertrand et al. (US 2020/0165526 A1) in view of McNamara et al. (US 2017/0233657 A1), further in view of KR 10-2021-0098036 A.
Claim 1
Bertrand teaches a process for pyrolysis of waste plastics comprising feeding plastic material to a pyrolysis reactor (e.g., ¶¶ [0047]-[0054]); heating the plastic in the substantial absence of oxygen to pyrolysis temperatures that encompass the claimed range (e.g., ¶¶ [0056]-[0068]); maintaining the material in the reactor for a sufficient residence time to generate pyrolysis vapors (¶¶ [0060]-[0068]); condensing the pyrolysis vapors to recover liquid hydrocarbons (¶¶ [0071]-[0078]); and recovering liquid hydrocarbon products in substantial yields (¶¶ [0075]-[0083]). Bertrand does not expressly teach adjusting reactor pressure according to characteristic parameters of the plastic feedstock and/or pyrolysis products while maintaining the pressure between atmospheric pressure and 13 bar(a), as recited in step (d). McNamara teaches controlling reactor pressure and reactor operating conditions during plastic pyrolysis, including pressure monitoring, pressure regulation, reactor control valves, and control of pyrolysis vapors to maintain desired operating conditions (e.g., ¶¶ [0043]-[0055], [0070]-[0085]). KR 10-2021-0098036 A further teaches maintaining and regulating reactor pressure during staged plastic pyrolysis using inert gas introduction and pressure monitoring to stabilize the pyrolysis process (e.g., pp. 8-12). 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 Bertrand's process with the pressure-control techniques taught by McNamara and KR20210098036 in order to stabilize pyrolysis conditions, accommodate varying feedstock characteristics, improve liquid product yield, and optimize reactor operation, which are recognized goals in the pyrolysis art. Claim 2 Bertrand teaches monitoring product yield and product characteristics during pyrolysis (¶¶ [0075]-[0083]). McNamara teaches adjusting operating conditions in response to process conditions (¶¶ [0070]-[0085]). It would have been obvious to utilize product yield or measured product characteristics as control parameters for reactor pressure. Claim 3 Bertrand teaches processing mixed plastic waste having varying composition (¶¶ [0038]-[0046]). Claims 4 and 5 McNamara teaches dynamic reactor pressure control using valves and control systems, resulting in pressure varying over time and within portions of the system (¶¶ [0048]-[0055], [0072]-[0085]). Claims 6 and 7 Bertrand teaches residence times encompassing the claimed ranges (¶¶ [0060]-[0068]).
Claim 9 Bertrand teaches waste plastic feedstocks containing contaminants and non-plastic materials. ¶¶ [0038]-[0046]. Claim 11 Bertrand teaches recycling condensed liquid hydrocarbons back to the reactor or process. ¶¶ [0078]-[0083]. Claims 12 and 13 KR20210098036 teaches introducing inert gases, including nitrogen, during the pyrolysis process to regulate reactor conditions and pressure (pp. 9-11). Claim 14 McNamara teaches pressure regulation by valves controlling vapor flow and downstream pressure regulation. ¶¶ [0070]-[0085]. KR20210098036 further teaches pressure regulation using inert gas supply. Claims 17 and 18 McNamara teaches automatic process control with rapid response to measured process variables (¶¶ [0070]-[0085]). Bertrand teaches measuring feed and product characteristics. It would have been obvious to employ conventional analytical instruments, including spectroscopic techniques, for rapid measurement and automatic process control. Many of the recited analytical techniques were well known for online chemical analysis before the effective filing date.
Claims 8 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over references as applied to claim 1 above, and further in view of Adam et al. (WO 2021/204818 A1)
Claim 8
Adam teaches integrating plastic recovery operations with downstream catalytic upgrading of waste-plastic pyrolysis products (e.g., pp. 1-8). It would have been obvious to feed non-recovered mixed plastics from a sorting operation to Bertrand's pyrolysis process.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the process of Bertrand to receive mixed plastic feedstock from a downstream plastics sorting and recovery facility as taught by Adam because doing so would have enabled the efficient utilization of otherwise unrecoverable mixed plastic waste, increased overall recovery of valuable hydrocarbons from plastic waste, and improved the economic efficiency of an integrated plastic recycling process.
Claim 15 Bertrand teaches characterizing plastic feedstocks according to composition (¶¶ [0038]-[0046]). Adam teaches analysis of plastic feedstock composition for process optimization (pp. 6-10).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the process of Bertrand to characterize the composition of the plastic feedstock using compositional indices, including hydrogen-to-carbon ratio and carbon content, as taught or suggested by Adam because knowledge of feedstock composition enables optimization of pyrolysis operating conditions, accommodates variability in mixed plastic feedstocks, and predictably improves product yield and quality.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over references as applied to claim 1 above, and further in view of Stankevitch (US 2003/0047437 A1). Stankevitch teaches secondary heating/cracking of pyrolysis vapors before condensation to improve product distribution (e.g., col. 5, ll. 20-60; col. 6, ll. 1-30).
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 Bertrand to further thermally treat the gaseous pyrolysis effluent before condensation as taught by Stankevitch because doing so would have promoted additional cracking of heavier hydrocarbons, improved the composition and yield of condensable liquid hydrocarbons, and predictably optimized the quality and recovery of the resulting pyrolysis oil.
Allowable Subject Matter
Claim 16 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
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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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Prem C Singh can be reached at 571-273-6381. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/TAM M NGUYEN/Primary Examiner, Art Unit 1771
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