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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 2/6/2026 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 1-15, 17, and 32 are ejected under 35 U.S.C. 103 as being unpatentable over Cheng et al. (US 2009/0134065 A1) in view of Mazanec et al. (US 2014/0303414 A1).
Cheng discloses a deep fluidized catalytic cracking process (DCC) wherein a hydrocarbon feed is contacted with a cracking catalyst to produce olefins (e.g., propylene) and spent catalyst is then separated and regenerated to burn off coke (carbon content) to restore the activity of the catalyst to produce a regenerated catalyst. The regenerated catalyst is then recirculated back to the cracking zone to contact with the hydrocarbon feed. The catalyst/additive comprises pentasil zeolite (e.g., ZSM-5), 0.7 to about 4 wt. % (e.g., 1.6 and 2.4 %) of iron oxide, and 5-20 wt.% of phosphorous (e.g., P2O5) and has an average particles size from about 20 – 200 microns. The catalyst can be comprised an additional catalyst (e.g., X or Y zeolite). See [0018], [0035], [0044], [0072], [0098], [0100], [0102], [0122]; tables 1, 2, 6.
Cheng does not teach an amount of coke on a regenerated catalyst.
Mazanec discloses a cracking process including a regenerating step to produce a regenerated catalyst comprising about 250 ppm (.025 wt.% ) to 0.3 wt. % coke (carbon content). See [0059].
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to apply Mazanec’s teachings regarding controlled oxidative regeneration to Cheng’s FCC pentasil catalyst system in order to regulate the amount of residual coke remaining on the regenerated catalyst. Residual coke level on regenerated FCC catalyst is a recognized operational variable that affects catalyst activity and heat balance in fluid catalytic cracking systems. Mazanec teaches that the oxidative regenerator can be operated under controlled conditions to achieve specific residual coke levels, including values within the claimed range (250 ppm to 0.3 wt.%). A person of ordinary skill in the art would have reasonably expected that controlling regenerator severity to achieve such coke levels would optimize catalyst performance and process efficiency in an FCC system such as that of Cheng.
Cheng does not teach the regenerated catalyst exhibits a Davison Attrition Index (DI) of less than 5. However, the catalyst of Cheng is essentially the same as the claimed catalyst. It would be expected that catalyst of Cheng would have an attrition resistance DI as claimed.
Cheng does not teach that the product stream comprises propylene in an amount of at least 10 wt. %.
It would have been obvious to one having ordinary skill in the art to optimize the known pentasil FCC system of Cheng by controlling regeneration severity and residual coke level as taught by Mazanec in order to enhance light olefin production, including propylene yield, because propylene yield is a recognized result-effective variable in FCC processes and was a known objective of pentasil additive use.
Response to Arguments
Applicant argues that Mazanec would motivate a person of ordinary skill in the art to leave higher amounts of coke on the catalyst because removal to very low levels may be economically unattractive. However, Mazanec expressly discloses regenerated catalysts having residual coke levels including 0.3%, 0.2%, 0.1%, 1000 ppm, and 250 ppm or less (see Mazanec ¶[0059]). Thus, Mazanec identifies the entire claimed range (0.005–0.30 wt.%) as viable embodiments. While Mazanec states that it may be economically unattractive to remove coke to extremely small quantities, Mazanec does not criticize or discourage operation at coke levels within the claimed range. Rather, it teaches that complete removal of coke is unnecessary and that a range of residual coke levels may be maintained depending on operational objectives.
Applicant asserts that Mazanec teaches that performance is unaffected up to 0.59 wt.% coke and therefore would discourage operation below 0.3 wt.%. This argument is not persuasive. Mazanec does not criticize or discredit lower coke levels. Instead, Mazanec identifies a broad range of residual coke levels as workable embodiments. The mere disclosure that higher coke levels may be tolerated does not constitute teaching away from lower coke levels. A reference does not teach away simply because it describes alternative embodiments or discusses trade-offs.
The limitation that the iron oxide is “primarily in an oxidized state” does not distinguish over the prior art combination. Cheng employs iron oxide (Fe₂O₃) in pentasil additives. Mazanec regenerates catalysts in an oxidative regenerator. Oxidative regeneration would inherently result in iron being predominantly in an oxidized state. Applicant has not shown that the prior art regeneration conditions would produce iron in a reduced state or that special conditions beyond ordinary FCC regeneration are required.
The argument about 10 wt.% Propylene limitation is not persuasive because pentasil-containing FCC additives are known to increase light olefin yield, including propylene. Propylene yield is a recognized result-effective variable influenced by catalyst composition, additive concentration, coke level, and reaction severity. Optimizing known parameters within disclosed ranges would have reasonably been expected to increase propylene yield, including to levels of at least 10 wt.%.
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