DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 25 September 2025 has been entered.
Claim Status
Claims 1 and 11 are amended. Claims 7, 9, and 14-15 are cancelled. Claims 11-13 are withdrawn due to an earlier restriction requirement.
Claims 1-6, 8, and 10 are pending for examination below.
Response to Arguments
Applicant’s arguments and amendments, see Remarks, filed 25 September 2025, with respect to the rejection(s) of claim(s) 1-6, 8, and 10 under USC 103 over Davydov in view of Moller have been fully considered and are persuasive. Davydov does not teach the presence of aromatics in the product as now required, and Moller does not provide motivation to filter a gas comprising aromatics. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of newly discovered prior art in view of the amendment.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-6, 8, and 10 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
With regard to claim 1, the claim recites “hot gas filter”. The term “hot gas” is a relative term which renders the claim indefinite. The term “hot gas” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
For purposes of examination, while the term “hot gas filter” is used in the chemical arts to mean a filter which is often used to filter waste gases, the scope of what temperature constitutes “hot gas” is unclear as the temperature range is not a specific temperature range in the art and is not mentioned in the specification with regard to the specific reaction claimed. Thus, the Examiner will consider that any filter which filters a composition which is at a temperature which overlaps the claimed cooling temperature meets the requirements to be a hot gas filter as claimed. Appropriate clarification and/or amendment are respectfully requested.
With regard to claims 2-6, 8, and 10, the claims are rejected as being dependent on a rejected base claim.
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 10 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 10 recites that the product comprises “at least ethylene and propylene”. However, both ethylene and propylene are already required by claim 1 as amended. Thus, claim 10 does not further limit claim 1.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 USC § 103
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.
Claims 1, 4-6, 8, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Uppili et al. (WO 2020/252228).
With regard to claims 1, 4-6, 8 and 10, Uppili teaches a method for conversion of plastics to hydrocarbons (paragraph [0002]) comprising the following steps:
a) feeding a plastic feed comprising polyolefins and other polymers (instant claim 8) (paragraph [0025]) and diluent steam to a fluidized bed reactor at a temperature of 500-900°C and a residence time of 0.1 to 5 seconds (paragraphs [0033]-[0034]). The range of 500-900°C encompasses the range of 680-740°C of instant claim 1 and the range of 700-730°C of instant claim 4, and the range of 0.1 to 5 seconds overlaps the ranges of less than 4 seconds of instant claim 1, less than 3 seconds of instant claim 5, and 2-3 seconds of instant claim 6, rendering the ranges prima facie obvious. Uppili further teaches the product from the reactor includes ethylene, propylene (instant claim 10), butadiene, other olefins (paragraph [0040]) and aromatics (paragraph [0037]). Uppili does not use the term “gasification” to describe the reaction taking place in the reactor. However, as Uppili teaches a similar plastic feed comprising polyolefins and reacting at similar temperature and time with steam and in a similar fluidized bed reactor to produce a similar product, one of ordinary skill in the art expects that the reaction taking place in Uppili includes the claimed gasification reaction, absent evidence to the contrary.
b) cooling the pyrolysis effluent to below 500°C at the end of the reaction time (paragraph [0033]) to stop the reaction (paragraph [0037]). The range of below 500°C overlaps the range of 400-600°C of instant claim 1, rendering the range prima facie obvious.
c) a filtration step to remove fine particles from vapor, where the filtration step can be located downstream from the separation stage or downstream from one or more other stages, wherein the other stages include the cooling stage (paragraph [0063]).
Uppili teaches that the inclusion of steam increases the yield of ethylene and propylene from the process (paragraph [0034]).
Uppili does not specifically teach i) the time period of the cooling, ii) the filtration located after the cooling, or iii) that the filter is a hot gas filter.
With regard to i) the time period, the time period of the cooling step affects how quickly the reaction stops. Thus, the time for the cooling step is a result-effective variable, and can be optimized. Therefore, it would have been obvious to one having ordinary skill in the art to have determined the optimum value of a time period of the cooling step to be below 2 seconds, as claimed, because it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. See MPEP 2144.05(II).
With regard to ii) the filtration located after the cooling, it would have been obvious to one of ordinary skill in the art at the time of the invention to place a filter after the cooling, as claimed, because Uppili teaches filtering and that the filtering can be located after separation or after one or more other stage of the process, where the other stages include the cooling stage.
With regard to iii) the hot gas filter, Uppili teaches filtering the product vapor where the filtration can be located after tooling (paragraph [0063]) and that the cooling reduces the temperature to below 500°C which overlaps the claimed range of 400-600°C. Thus, one of ordinary skill in the art would reasonably conclude that the filter of Uppili which is present in the same location and used on a vapor stream at a similar temperature is a hot gas filter, as claimed, absent any evidence to the contrary.
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Uppili et al. (WO 2020/252228) as applied to claim 1 above, and further in view of Davydov (US 2022/0010218).
With regard to claim 2, Uppili teaches the fluidized bed reactor (paragraph [0033]).
Uppili fails to teach the fluidized bed reactor is specifically a bubbling fluidized bed reactor.
Davydov teaches a process for producing olefins from polyolefins containing plastic (paragraph [0002]) in a fluidized bed reactor (paragraph [0019]). Davydov further teaches the fluidized bed reactor operates as a dense bubbling bed (paragraph [0027]) at a similar temperature of 600-1100°C (pargraph [0020]) and residence time of 0.5 to 30 seconds. Thus, Davydov teaches that it is known to convert plastics to olefins in a bubbling bed fluidized bed reactor when the temperature and residence time are similar to the temperature and residence time of Uppili.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to use a bubbling bed fluizied bed reactor in the process of Uppili because Uppili teaches conversion of plastics comprising polyolefins to a product comprising olefins in a fluidized bed reactor, but does not specifically teach the operating regime of the fluidized bed reactor, and Davydov teaches that it is known and suitable to convert polyolefins plastics to olefins at a similar temperature and residence time in a bubbling bed fluidized bed reactor.
With regard to claim 3, Uppili in view of Davydov does not specifically teach the yield of the propylene is at least 15 wt%. However, Uppili in view of Davydov teaches a similar gasification process in a similar bubbling bed reactor of a similar plastic feed comprising polyolefins and other polymers at a similar temperature, quenching at a similar temperature, and filtering, and producing a similar product comprising ethylene, propylene, butadiene, aromatics, and other hydrocarbons, as recited above. Thus, one of ordinary skill in the art would reasonably expect that the process of Uppili provides a propylene yield of at least 15 wt%, as claimed, absent any evidence to the contrary.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALYSSA L CEPLUCH whose telephone number is (571)270-5752. The examiner can normally be reached M-F, 8:30 am-5 pm, EST.
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/Alyssa L Cepluch/Examiner, Art Unit 1772
/IN SUK C BULLOCK/Supervisory Patent Examiner, Art Unit 1772