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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 23 February 2026 has been entered.
Response to Amendment
Amendment to claim 1 and addition of new claim 22 are noted.
Response to Arguments
Applicant’s arguments with respect to claim 1 have been considered but are moot because the arguments do not apply to the grounds of rejection being used in the current rejection.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-4, 6-18 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Wilhelmus et al (WO 2018/224482) in view of Luengo Marin et al (WO 2011/079894), Narayanaswamy et al (US 2014/0228606), and Schabel et al (US 2017/0283706).
Wilhelmus is cited from the English language equivalent (US 2021/0277202).
Regarding claims 1, 2 and 7, Wilhelmus discloses a pyrolysis process comprising:
(a) introducing a pyrolysis feedstock composed of a material comprising a mixture of polycarbonate-containing compound and polystyrene-containing compound into a reactor (see [0024]-[0025]; [0027]; [0031]);
(b) degrading the material of the pyrolysis feedstock at a temperature of 300 to 450°C to obtain a gas-phase product as pyrolysate, wherein the pyrolysate is discharged from the reactor during breakdown (see [0031]-[0032]; [0076], temperature within or overlapping the claimed ranges); and
(c) cooling discharged pyrolysate to obtain a pyrolysate condensate product (see [0032]-[0033]).
Regarding step (a), Wilhelmus does not disclose introducing a catalyst as a component of the pyrolysis feedstock, as claimed.
Luengo Marin is directed to pyrolysis (thermolysis) of waste polymer-based materials (see [0001]; [0018]; [0039]). In particular, Luengo Marin discloses adding a conventional cracking catalyst to the starting material just before feeding to the reactor. The catalyst permits performing the reaction at lower temperatures and shorter residence times than without a catalyst. Furthermore, the catalyst favors the yield and reduces undesired secondary products (see [0055]).
Narayanaswamy is directed to pyrolysis of a plastic feedstock, including feeds comprising polystyrene and polycarbonate (see [0001]; [0016]; [0077]). Pyrolysis is carried out in a reactor in the presence of a catalyst composition (see [0006]). Like Luengo Marin, suitable catalysts include conventional FCC catalysts and may comprise silicon aluminum phosphates, aluminum oxide, and clay (e.g., kaolin) (see [0012]; [0066]; [0071]). Narayanaswamy discloses that use of the catalyst allows for tunable process yields to desired olefins and aromatic products (see [0075]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the process of Wilhelmus by adding a catalyst to the feed material, as suggested by Luengo Marin and Narayanaswamy, including those within the scope of the instant claimed invention, in order to facilitate carrying out the reaction at lower temperatures and shorter residence time as well as favor yield to desired products and reduce formation of undesired secondary products.
Regarding step (b), Wilhelmus is silent with respect to an amount of oxygen gas in the reactor. However, the office notes that the reaction in Wilhelmus is pyrolysis and only requires decomposition via the introduction of thermal energy (see [0031]), i.e., no oxygen is required to carry out pyrolysis. A person of ordinary skill in the art would therefore understand that the pyrolysis reaction in Wilhelmus occurs without the introduction of oxygen gas into the reactor, i.e., 0% by volume of oxygen, and is thus considered in line with the claimed embodiment.
Furthermore, Wilhelmus does not explicitly state that a residue is obtained during the degrading step. However, the formation of solid residues as a by-product in the pyrolysis of polymer feedstocks, including those containing polycarbonate and polystyrene, at temperatures in line with those claimed and disclosed by Wilhelmus is considered to be inherent, as evidenced by Schabel (see [0024]; [0050]; claims 6 and 7). Solid residue is removed from the pyrolysis apparatus and collected (see [0047]).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to include solids removal as a part of the pyrolysis step of Wilhelmus, as suggested by Schabel, in order to remove and collect any solid by-products formed during the pyrolysis reaction, so as to avoid solids accumulation in the reactor.
Regarding step (c), Wilhelmus does not explicitly disclose the temperature to which the gas phase is cooled. However, given that the reference discloses condensing low-molecular weight products arising from pyrolysis reaction (see [0032]; [0081]), the corresponding temperature is lower than that of the pyrolysis reaction and must be such that condensation of the product(s) occurs. Such temperature would be, at the very least, overlapping with that claimed. Furthermore, a person of ordinary skill in the art would determine the suitable temperature which effects condensation of the desired products. Absent a showing of criticality or unexpected results, the claimed cooling temperature is not considered to distinguish over the cited prior art.
Regarding claim 3, Wilhelmus discloses wherein the introduced pyrolysis feedstock is temperature controlled at 250 to 500°C and the residence time in the pyrolysis reactor is 0.1 to 60 minutes, within or overlapping the claimed ranges (see [0031]).
Regarding claim 4, Wilhelmus discloses wherein the discharge of the pyrolysate from the reactor is ensured by suction (see [0091]).
Regarding claim 6, the description of the process throughout the Wilhelmus reference implies that the process is continuous. Furthermore, making a process continuous is prima facie obvious. MPEP 2144.04 V E.
Regarding claim 8, Schabel discloses purging the reactor vessel packed with feedstock material with nitrogen (see [0099]).
Regarding claims 9-11, Wilhelmus discloses a feedstock containing polystyrenes and polycarbonates, as discussed above. The selection of suitable starting materials is prima facie obvious absent new or unexpected results. Accordingly, the claimed specific characteristics of the feedstock materials are not considered to patentably distinguish over the cited prior art.
Regarding claims 12-15, the office notes that the presence of phosphorus-containing compound is optional, wherein the total amount may be 0% by weight.
Regarding claim 16, Wilhelmus discloses wherein the material is introduced into the reactor in the form of solid particles (see [0044]-[0045]).
Regarding claim 17, Wilhelmus discloses wherein the pyrolysis feedstock also comprises at least one filler (see [0028]-[0029]).
Regarding claim 18, Wilhelmus discloses wherein the material is present in the feedstock in a total amount of 0.1 to 100 wt% (see [0025]; [0027]), overlapping the claimed range.
Regarding claim 22, Narayanaswamy discloses wherein the catalyst is a heterogenous catalyst comprising solid particles having a particle size (diameter) in the range of greater than 0 to 150 microns (see [0066]), overlapping the claimed range.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Wilhelmus in view of Luengo Marin, Narayanaswamy, and Schabel, as applied to claim 1, in further view of Kikuya et al (JP 2011-236337).
Kikuya is cited from the English machine translation, provided herewith.
Regarding claim 5, Wilhelmus does not explicitly disclose that the discharge of pyrolysate from the reactor is ensured by a gas stream passed through the reactor. However, it is noted that the reference discloses that a suitable reactor for carrying out pyrolysis is a fluidized bed reactor (see [0077]).
In this regard, reference is drawn to Kikuya, which is directed to thermal decomposition of resin in a fluidizing bed reactor (see Abstract). An inert gas is fed as a fluidizing gas to the reactor via fluidizing gas supply channel 2 product gas generated in the reactor exits together with the fluidizing gas (see Fig. 1; pp. 3-4, 6).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to use a fluidizing gas in the process of Wilhelmus, where Wilhelmus suggests that the process may be carried out in a fluidized bed reactor and Kikuya provides the details for how such a process is carried out, including use of an inert fluidizing gas which exits with the gas product.
With respect to the superficial velocity of the gas stream, a person of ordinary skill in the art would determine the optimum velocity at which to supply the gas to ensure fluidization of the reactor bed and subsequent exit of the product gas from the reactor. Absent a showing of criticality or unexpected results, the claimed velocity is not considered to patentably distinguish the instant claims over the cited prior art.
Conclusion
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/Renee Robinson/Primary Examiner, Art Unit 1772