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 1-8, 10, 14-16, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Streiff et al. (US 2018/0371326 A1) in view of Subramani et al. (WO 2010/113174A1) and Evans et al. . (WO 2022/155525 A1).
Streiff discloses a fluid catalytic cracking (FCC) process wherein a waste plastic ([0079], [0083], [0086]) feedstock is melted to provide a neat form ([0079]). The melted feedstock is then contacted with a fresh catalyst ([0025]) and/or a deactivated catalyst ([0057]) comprising ZSM-5 ([0046]) in a FCC process to produce a product which is then fractions and recovered ([0079]) to produce a fraction comprising gasoline ([0083], [0084]). The FCC process is operated at a temperature of from 350-600o C ([0079]). The plastic comprises one or more polyesters and one or more polyolefins (e.g., high density polyethylene and polypropylene) ([0070], [0086] [0092]).
Streiff does not teach that the catalyst comprises at least about 90 wt. % of a phosphorus-containing ZSM-5, does not teach that the catalyst is treated with steam prior to contact with a feedstock, does not explicitly teach that the polyethylene having a melting point of from about 35o C to 100o C or the low or high density of the polyolefins as claimed, does not teach that the plastic feedstock is solid or a semi-melted state. and does not teach that the product stream comprises about 30-60 wt. % of gasoline fraction.
Evans teaches a phosphorus-containing ZSM-5 light olefins additive having a ZSM-5 content and phosphorus content collectively meeting the claimed requirement of at least 90 wt.% phosphorus-containing ZSM-5 light olefins additive. Specifically, Evans discloses a cracking catalyst comprising about 80 wt. % of ZSM-5 and 0-20 wt. % of phosphate (Abstract; [0018], [0039], [0041]).
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 Streiff by utilizing a catalyst comprising at least 90 wt. % of phosphorus containing ZSM-5 as suggested by Evans in order to enhance cracking selectivity.
Subramani discloses a FCC process wherein the catalyst is deactivated by treating with steam at a temperature of 810o C prior to use. See pages 17, lines 9-20; page 19, lines 2-5; page 22, lines 1-8; page 23, lines 1-8.
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 Streiff by treating the catalyst with steam as suggested by Subramani to increase the production of LPG and propylene.
Streiff Further teaches that FCC catalyst systems may employ fresh FCC catalyst, equilibrium FCC catalyst, or mixtures thereof. Evans teaches a phosphorus-containing ZSM-5 light olefins catalyst/additive. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ the phosphorus-containing ZSM-5 catalyst taught by Evans as the catalyst utilized in the plastic cracking process of Streiff and to omit additional catalyst components because catalyst composition and catalyst inventory are recognized result-effective variables affecting gasoline selectivity and hydrocarbon distribution. Selecting the phosphorus-containing ZSM-5 catalyst as the sole catalyst would have been no more than routine optimization of catalyst formulation and inventory to obtain a desired product slate
Regarding the limitation that the catalyst is the only catalyst, once it is obvious to employ a high-loading ZSM-5 cracking catalyst as suggested by Evans, it would have been an obvious design choice to operate the cracking process using that catalyst formulation alone rather than in combination with other FCC catalysts, depending on desired product selectivity and catalyst inventory considerations. Therefore, 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 Streiff by employing a steam-treated, high-loading ZSM-5 cracking catalyst that is free of metal impregnation, as suggested by Subramani and Evans, in order to tune catalyst acidity and gasoline selectivity.
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 Streiff by utilizing a low and high density of polyethene and polypropylene as claimed because it is within the level of one of skill in the art to use any type of density of polyethene and polypropylene with expectation that either high or low density polyethene and polypropylene would be effectively treated in the process of Streiff. Consequently, a low density polyethylene would have a melting point as claimed.
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 Streiff by utilizing a plastic feedstock in a solid or semi-melted neat-form because it would be expected the such neat-forms would be successfully treated in the process of Streiff because the mixture of catalyst plastic feedstock is then heated up to a temperature of from 350-600o C and reacted in the reactor.
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 Streiff by producing a product stream comprising 30-60 wt. % of gasoline as claimed because of the similarities between the claimed process and the modified process of Streiff. See table 2 and example data show gasoline yield within the claimed range (e.g., approximately 35-38 wt. % gasoline).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over references as applied to claim 1 above, and further in view of Narayanaswamy et al. (US 2014/0228606 A1).
The process of Streiff is as discussed above.
Streiff does not disclose that the catalyst is regenerated.
The process of Narayanaswamy is as discussed below.
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 Streiff by regenerating the catalyst as suggested by Narayanaswamy to at least partially remove coke to renew the catalyst.
Claims 1-8, 10, 14-17, and 22-26 are rejected under 35 U.S.C. 103 as being unpatentable over Narayanaswamy et al. (US 2014/0228606 A1) in view of Evans et al. . (WO 2022/155525 A1) and Subramani et al. (WO 2010/113174 A1).
Narayanaswamy teaches process for converting solid waste plastic feedstock to hydrocarbon product [0134]. The feedstock comprising low and high density of polyethylene ([0016], table 2) in a neat form is contacted with a fresh/deactivated catalyst comprising ZSM-5 ([0013], table 1, [0069]) in FCC reaction zone to produce a product comprising gasoline ([0108], [0109]). The FCC reaction zone is operated at a temperature of from 420-730o C ([0006], [0017], [0019]) and at a catalyst to oil ratio from about 2:1 to about 10:1 ([0081]). The catalyst is treated with steam (figure 1, stripper) at a temperature of at least 500o C. The catalyst is regenerated at a temperature of from 600-800o C ([0063]), at a hydrocarbon partial pressure of 100 to about 1100 kPa ([0081]).
Narayanaswamy does not teach that the catalyst comprising 80 wt. % of ZSM-5, does not teach that the catalyst is treated with steam prior to contact with a feedstock, does not explicitly teach that the polyethylene having a melting point of from about 35o C to 100o C or the low or high density of the polypropylene as claimed, does not teach that the plastic feedstock is semi-melted state or liquid state, and does not teach that the product stream comprises about 30-60 wt. % of gasoline fraction.
Evans teaches a phosphorus-containing ZSM-5 light olefins additive having a ZSM-5 content and phosphorus content collectively meeting the claimed requirement of at least 90 wt.% phosphorus-containing ZSM-5 light olefins additive. Specifically, Evans discloses a cracking catalyst comprising about 80 wt. % of ZSM-5 and 0-20 wt. % of phosphate (Abstract; [0018], [0039], [0041]).
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 Narayanaswamy by utilizing a catalyst comprising about 90 wt. % phosphorus-containing ZSM-5 as suggested by Evans in order to enhance cracking selectivity.
Subramani discloses a FCC process wherein the catalyst is deactivated by treating with steam. See pages 17, lines 9-20; page 19, lines 2-5; page 22, lines 1-8; page 23, lines 1-8.
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 Narayanaswamy by treating the catalyst with steam as suggested by Subramani to increase the production of LPG and propylene.
Regarding the limitation that the catalyst is the only catalyst, once it is obvious to employ a high-loading ZSM-5 cracking catalyst as suggested by Evans, it would have been an obvious design choice to operate the cracking process using that catalyst formulation alone rather than in combination with other FCC catalysts, depending on desired product selectivity and catalyst inventory considerations. Therefore, 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 Narayanaswamy by employing a steam-treated, high-loading ZSM-5 cracking catalyst that is free of metal impregnation, as suggested by Subramani and Evans, in order to tune catalyst acidity and gasoline selectivity.
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 Narayanaswamy by utilizing a low and high density of polypropylene as claimed because it is within the level of one of skill in the art to use any type of density of polypropylene with expectation that either high or low density polypropylene would be effectively treated in the process of Narayanaswamy. Consequently, a low density polyethylene would have a melting point as claimed.
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 Narayanaswamy by utilizing a plastic feedstock in a semi-melted, or melted neat-form because it would be expected the such neat-form would be successfully treated in the process of Narayanaswamy because the mixture of catalyst plastic feedstock is then heated up to a temperature of from 600-800o C and reacted in the reactor.
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 Narayanaswamy by producing a product stream comprising 30-60 wt. % of gasoline as claimed because of the similarities between the claimed process and the modified process of Narayanaswamy.
Regarding claim 22, 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 Narayanaswamy’s teaching that gasoline yield is a key tuning target and is routinely adjusted by catalyst composition and FCC severity, to optimize the operating conditions and catalyst formulation of the combined Narayanaswamy/Evans/Subramani process such that the gasoline fraction in the total product stream falls within a commercially useful range such as about 30 to about 60 wt.%, as a matter of routine optimization of result-effective variables (see MPEP § 2144.01).
Regarding claims 23-24, as applied to claim 1, it is implicit from Narayanaswamy that fresh FCC catalysts and additives are manufactured substantially free of such heavy metal contaminants and that metal contamination arises only as a result of exposure to hydrocarbon feed and metals present therein.
Regarding claim 23 additionally recites that “the non-metal impregnated, steam-treated deactivated catalyst is free of a metal contaminant.” Claim 23 does not recite any structural change to the ZSM-5-containing additive itself, but merely characterizes the catalyst by its contamination history (fresh vs. used). Selecting a fresh, essentially metal-free FCC light olefin additive for use in a plastics FCC process, rather than an equilibrated, metal-contaminated catalyst, would have been an obvious design choice to one of ordinary skill in the art in view of Narayanaswamy’s teachings on ECAT and the well-known fact that fresh additives are initially free of feed-borne metals. The presence or absence of contaminant metals such as Ni or V is not a fundamental structural difference in the ZSM-5/additive formulation, but rather an inherent condition of use dictated by whether the catalyst has been previously circulated. As such, reciting that the additive is “free of metal contaminant” does not impart patentable weight beyond the obvious selection of a fresh catalyst.
Regarding claim 24 further specifies that the metal contaminant comprises one or more of sodium, potassium, magnesium, calcium, vanadium, nickel, and iron. Such metals are recognized in the FCC art as typical contaminants arising from crude-derived feeds and feed pretreatment (see, e.g., Narayanaswamy’s specific mention of vanadium in equilibrium FCC catalyst at ¶[0057], and Applicant’s own specification describing similar metal species as typical contaminants). It would have been obvious for one of ordinary skill in the art, when characterizing a “metal-contaminated” versus “metal-free” FCC catalyst, to identify conventional FCC contaminant metals such as Na, K, Mg, Ca, V, Ni, and Fe. Reciting this illustrative list of conventional FCC contaminants does not confer patentability (see MPEP § 2144.05 regarding selection of known species and characterization of known contaminants).
Regarding claims 25 and 26, As applied to claim 1, Evans teaches the use of ZSM-5-based light olefins additives at high loadings (about 80 wt.% and higher) and 0-20 wt. % phosphate in FCC catalyst formulations.
Evans teaches that increasing ZSM-5 content in FCC light olefin additives increases cracking activity and light olefin production. In view of Evans, once it is obvious to employ ≥90 wt.% ZSM-5 + phosphorus additive because Evans teaches the catalyst comprises about 80 wt. % of zeolite and 0-20 wt. % phosphate in the catalyst, it would have been an obvious matter of routine optimization to further increase the proportion of the additive to 90 wt.%, 95 wt.%, or even 100 wt.% to achieve a desired selectivity profile, especially in a system focused on light olefins and gasoline production. The exact numerical threshold (80, 90, 95, 100 wt.%) represents routine tuning of the proportion of additive in the circulating catalyst inventory.
Response to Arguments
Applicant argues that the collective teachings of Streiff, Subramani, and Evans, as well as Narayanaswamy, Subramani, and Evans, fail to teach or suggest the amended limitation requiring a non-metal impregnated, steam-treated deactivated catalyst comprising at least 90 wt.% of a phosphorus-containing ZSM-5 light olefins additive, wherein the catalyst is the only catalyst. Applicant further argues that Subramani teaches combining a steam-deactivated ZSM-5 additive with other catalyst components and therefore would not motivate one of ordinary skill in the art to employ the steam-treated catalyst as the sole catalyst. The argument is not persuasive.
The rejection does not rely upon Subramani as teaching the entire claimed catalyst system. Rather, Subramani is relied upon for its express teaching that a ZSM-5-containing FCC additive may be hydrothermally deactivated by treatment with steam prior to use (see, e.g., Example 8). Evans is relied upon for teaching a phosphorus-containing ZSM-5 light olefins catalyst/additive having the high ZSM-5 loading recited in the claims, and Narayanaswamy and Streiff are relied upon for teaching FCC processing of waste plastic feedstocks to produce gasoline-range hydrocarbons.
Applicant's reliance on Example 8 of Subramani is misplaced. Example 8 merely discloses one embodiment employing a steam-deactivated ZSM-5 additive in combination with other catalyst components. Subramani does not state, suggest, or imply that a steam-deactivated ZSM-5 catalyst must be used only in combination with other catalysts, nor does Subramani criticize, discredit, or otherwise discourage use of such catalyst as the sole catalyst. Accordingly, Subramani does not teach away from the claimed configuration.
Applicant argues that Subramani teaches the steam-treated ZSM-5 additive only in combination with Catalyst-B and Catalyst-C and therefore would not have suggested use of the catalyst as the sole catalyst. This argument is not persuasive. Subramani is relied upon only for its teaching of steam deactivation of a ZSM-5-containing catalyst. Evans is relied upon for the phosphorus-containing ZSM-5 catalyst composition, and Streiff/Narayanaswamy are relied upon for FCC processing of plastic feedstocks. Subramani does not criticize, discredit, or otherwise discourage use of a steam-treated ZSM-5 catalyst as the sole catalyst and therefore does not teach away from the claimed invention. The cited references collectively recognize catalyst composition and catalyst inventory as variables affecting product selectivity. Accordingly, employing the phosphorus-containing steam-treated ZSM-5 catalyst as the sole catalyst would have been an obvious matter of routine catalyst optimization.
Further, the cited references collectively recognize that FCC catalyst composition and ZSM-5 content are variables used to control cracking activity and product selectivity. Narayanaswamy teaches catalyst systems containing substantial amounts of ZSM-5 catalyst, including catalyst formulations employing extremely high ZSM-5 loadings. In view of these teachings, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ the high-loading phosphorus-containing ZSM-5 catalyst taught by Evans as the catalyst used in the FCC plastic-cracking processes of Narayanaswamy or Streiff, and to utilize the steam-deactivation technique taught by Subramani in order to adjust catalyst acidity and product selectivity.
Applicant additionally contends that the rejection is based upon improper hindsight reconstruction. This argument is not persuasive. The references are all directed to closely related FCC catalyst technology and collectively address catalyst formulation, catalyst deactivation, and hydrocarbon production from FCC feedstocks. The rejection relies on express teachings in the references themselves and does not use Applicant's disclosure as a template for reconstructing the claimed invention. The combination is supported by the references' shared objective of modifying FCC catalyst properties to achieve desired hydrocarbon product distributions.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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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