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 .
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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 22 May 2026 has been entered.
Election/Restrictions
As set forth in the prior Office actions, claims 25, 27, and 28 stand withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 29 August 2025.
Response to Arguments
Applicant’s arguments regarding the rejections under 35 USC § 112(b), pages 6-7 of the reply filed 22 May 2026, have been considered and are persuasive in part. However, explicit clarification in the language of claim 1 is required to overcome the confusion between “one or more vitrification materials” and “said vitrification materials”. Amending “said vitrification materials” to “said one or more vitrification material” would overcome this rejection.
Similarly, parallel language making it explicitly clear that chemical recycling solvolysis facility of claim 22 is the same as the solvolysis facility of claim 1 is required.
Applicant’s arguments, see pages 7-8 of the reply filed 22 May 2026, with respect to the rejections under 35 USC § 103 have been fully considered and are persuasive. Therefore, the prior rejection have been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Bergmann et al. (US 2012/0266532 A1), as analyzed below.
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, 5-8, 10, 13, 15, 18-20, and 23-24 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.
Claim 1 recites “said vitrification materials” in line 9. There is insufficient antecedent basis for this limitation, as it is unclear if “said vitrification materials” refers to the same materials as the “one or more vitrification materials” when only one such material is present. For the purposes of further examination, “said vitrification materials” is interpreted as meaning “said one or more vitrification materials.”
Claims 5-8, 10, 13, 15, 18-20, and 23-24 each depend upon claim 1 without resolving these issues of antecedent basis and are likewise rejected.
Claim 23 recites the limitation "said solvolysis chemical recycling facility”. There is insufficient antecedent basis for this limitation in the claim, as while claim 1 recites a “solvolysis facility,” it is unclear if this is the same as the solvolysis chemical recycling facility of the instant claim.
Claim 24 recites the limitation “said vitrification material stream.” There is insufficient antecedent basis for this limitation in the claim, as claim 24 no longer depends from claim 22.
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.
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, 5-6, 13, 18, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Khan et al. (US 5,656,042 A) in view of Bergmann et al. (US 2012/0266532 A1).
Regarding claim 1, Khan teaches a method of producing synthesis gas comprising: feeding a waste plastic feedstock into a partial oxidation gasifier (scrap plastic materials which are used as feed…to a partial oxidation gas generator; column 2, lines 8-9), said waste plastic feedstock comprising waste plastic (polyethylene in a mixture comprising several types of plastics found in the household; column 7, lines 33-36) and one or more vitrification materials directly derived from said mixed waste plastic (associated inorganic matter [column 1, line 50], which include vitrification materials such as titania, alumina, aluminum, glass and barium carbonate [column 2, lines 22-33]); and partially oxidizing said waste plastic feedstock within said partial oxidation gasifier to produce said synthesis gas (column 1, lines 60-62).
Khan also teaches that the associated inorganic matter in the plastic waste stream, such as dyes, pigments, catalysts and fillers (column 2, lines 16-34), can be incorporated into the slag (noncombustible materials in the plastic materials, and the encapsulated material will flow from the reaction zone of the gas generator as substantially inert molten slag; column 5, lines 49-52). Khan further teaches that fillers include titania, talc, clays, alumina and barium carbonate (column 2, lines 23-24), which can be considered vitrification materials. Khan does not teach at least a portion of the vitrification materials being obtained from a decanter or a reactor purge of a solvolysis facility.
However, Bergmann also teaches methods of treating mixed waste plastic streams ([0001] and [0004]), and further teaches that the sediment in the solvolysis reactor of a solvolysis facility includes many of the same vitrification materials identified by Khan, including heavy metals, glass, alumina, and silicates ([0042]-[0059], [0087]-[0089]). Bergmann further teaches that these sediments are discharged from the solvolysis reactor ([0107]), and therefore meet the limitation of being a reactor purge.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add the reactor purge of the solvolysis facility taught by Bergmann to the method of Khan, thereby arriving at the instantly claimed invention. One of ordinary skill in the art would have been motivated to do so because Bergmann teaches that this stream contains many of the same components as those described by Khan as benefitting from being encapsulated in the inert slag generated by their process.
Regarding claim 5, modified Khan teaches the method of claim 1 where Khan teaches the partial oxidation gasifier operating in conditions that produce slag (by the aforesaid operating conditions…nontoxic slag [is produced];column 5, lines 25-27).
Regarding claim 6, modified Khan teaches the method of claim 5 where Khan teaches the slag including at least a portion of the said one or more vitrification materials derived from plastic material of said feedstock (inorganic matter in the solid carbonaceous plastic-containing material is safely captured …to produce nonhazardous slag; column 1, lines 16-19).
Regarding claim 13, modified Khan teaches the method of claim 1 where Khan teaches the feedstock to the partial oxidation gasifier includes leachable materials comprising chromium in the amount of 0.16 wt% of the feed, which falls in the instantly claimed range (ash makes up 58.3% of the feed, Table I, and Cr2O3 makes up 0.28% of the ash, Table II: 0.28% of 58.3% is 0.16%).
Regarding claim 18, modified Khan teaches the method of claim 1, where Khan also teaches that coal can be included in the feedstream (the aluminosilicate-containing material that is used as a feedstream in the process is a nonpolymeric material selected from the group of solid materials consisting of coal…; column 3, line 50-52).
Regarding claim 23, modified Khan teaches the method of claim 1, where Bergmann teaches the process occurring is a solvolysis process for chemical recycling ([0001]) and that the process may be a hydrolysis ([0041]), making the facility in which such a reaction occurs a hydrolysis chemical recycling facility.
Claims 7-8, 10, 15, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Khan et al. (US 5,656,042 A) in view of Bergmann et al. (US 2012/0266532 A1), as applied to claim 1 above, and further in view of Bai (US 2013/0240647 A1).
Regarding claim 7, modified Khan teaches the method of claim 1, but Khan does not teach sorting a mixed plastic waste stream into a heavies-enriched stream and a heavies-depleted stream.
However, Bai teaches methods of sorting mixed waste streams ([0008]), including for improved performance during gasification applications related to the conversion of these streams into chemical and fuel feedstocks ([0003]), and that these mixed waste streams include mixed plastic waste (Types of MSW components include, but are not limited to, plastics, including soft plastics and hard plastics (e.g., #1 to #7 plastics and other polymers such as Acrylonitrile-butadiene-styrene (ABS), Polyamide (also called nylon, PA), Poly(butylene terephthalate)--PBT); [0033]).
Bai further teaches sorting the mixed plastic waste into a heavies-enriched stream (244-246, Fig. 2, which comprises heavy materials such as ferrous and non-ferrous metals, as defined in the instant specification [0135]) and a heavies-depleted stream (235, Fig. 2), where a portion of one or more vitrification materials are included in the heavies-depleted stream (the [heavies-depleted] waste stream can be conveyed from the secondary shredder 235 to an additional density separator … the additional density separator can be used to ensure the waste stream is substantially free from metals, glass, and/or any other material that can, for example, have adverse effects on the material classification subsystem 220; [0053]); the materials recited by Bai (e.g., glass) are vitrification materials that are still present in the heavies-depleted stream.
Therefore, it would have been obvious to one of ordinary skill in the art to modify the method of Khan to first separate the mixed plastic waste into a heavies-enriched stream and a heavies depleted stream, where at least a portion of the vitrification materials are included in the heavies-depleted stream, as taught by Bai. One of ordinary skill in the art would have been motivated to do so because such sorting can remove non-processable waste, prohibitive items, and marketable recycles from the waste stream and improve its performance during gasification, as taught by Bai ([0020] and [0003]).
Regarding claim 8, modified Khan teaches the method of claim 7, where Bai teaches a density separation process on the heavies-depleted stream forms a stream enriched in vitrification materials (the waste stream can be conveyed from the secondary shredder 235 to an additional density separator … the additional density separator can be used to ensure the waste stream is substantially free from metals, glass, and/or any other material that can, for example, have adverse effects on the material classification subsystem 220; [0053]).
Khan further teaches the non-combustible materials from the plastic waste stream, which includes materials separated by the additional density separator of Bai such as glass, can be captured in the slag of the partial oxidation gasifier (column 5, lines 49-52), and later sold as a useful byproduct (column 5, lines 57-58).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use at least a portion of the one or more vitrification materials isolated from the heavies-depleted stream of Bai into the partial oxidation gasifier of Khan. One of ordinary skill would have been motivated to do so because it would allow them to convert waste material into a salable and useful product, as taught by Khan.
Regarding claim 10, modified Khan teaches the method of claim 1 where Bai teaches the mixed plastic feedstock being obtained by a separation of mixed plastic waste including a density separation process that produces a high density stream and a low density stream (materials with a density below a predetermined threshold pass to the material classification subsystem and material with a density above the predetermined threshold pass to a secondary subsystem [0043]), where the low density stream contains the plastic and fibers ([0050]). Bai further teaches that the plastics will have densities up to about 87 pounds per cubic foot (1.39 g/cc; [0028]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a mixed plastic feedstock in the method of modified Khan that was obtained by a separation of mixed plastic waste including a density separation process that produces a high density stream having a density above 1.39 g/cc and a low density stream having a density less than the density of the high density stream.
One of ordinary skill in the art would have been motivated to do so because Bai teaches that plastics have densities below this threshold, and will therefore be funneled to the low-density stream, while ferrous metals, non-ferrous metals, glass, dirt, and/or the like, which will have densities above this threshold, can be separated by such a density separation procedure ([0050]).
Regarding claim 15, modified Khan teaches the method of claim 1, but Khan does not teach sorting a mixed plastic waste stream into a heavies-enriched stream and a heavies-depleted stream, the heavies-enriched stream comprising one or more of ferrous metals, non-ferrous metal, glass, and dirt.
However, Bai teaches methods of sorting mixed waste streams ([0008]), including for improved performance during gasification applications related to the conversion of these streams into chemical and fuel feedstocks ([0003]), and that these mixed waste streams include mixed plastic waste (Types of MSW components include, but are not limited to, plastics, including soft plastics and hard plastics (e.g., #1 to #7 plastics and other polymers such as Acrylonitrile-butadiene-styrene (ABS), Polyamide (also called nylon, PA), Poly(butylene terephthalate)--PBT); [0033]).
Bai further teaches sorting the mixed plastic waste into a heavies-enriched stream (244-246, Fig. 2) and a heavies-depleted stream (235, Fig. 2), where the heavies-enriched stream comprises ferrous metal and non-ferrous metal (244, 245; Fig. 2).
Therefore, it would have been obvious to one of ordinary skill in the art to modify the method of Khan to first separate the mixed plastic waste into a heavies-enriched stream and a heavies-depleted stream where the heavies-enriched stream comprises ferrous metal and non-ferrous metal, as taught by Bai. One of ordinary skill in the art would have been motivated to do so because such sorting can remove non-processable waste, prohibitive items, and marketable recycles from the waste stream and improve its performance during gasification, as taught by Bai ([0020] and [0003]).
Regarding claim 20, modified Khan teaches the method of claim 1, and Khan further teaches that the mixed plastic stream contains about a trace to about 80 wt% of inorganic components (column 2, line 33-35), or about 20 wt% to less than 100% of carbonaceous plastic-containing material.
Khan does not teach separating a waste plastic to produce a vitrification materials stream comprising one or more vitrification materials and between 4% and 50% by weight of one or more plastic materials.
However, Bai teaches methods of sorting mixed waste streams ([0008]), including for improved performance during gasification applications related to the conversion of these streams into chemical and fuel feedstocks ([0003]), and that these mixed waste streams include mixed plastic waste (Types of MSW components include, but are not limited to, plastics, including soft plastics and hard plastics (e.g., #1 to #7 plastics and other polymers such as Acrylonitrile-butadiene-styrene (ABS), Polyamide (also called nylon, PA), Poly(butylene terephthalate)--PBT); [0033]). Bai further teaches separating a waste plastic to produce a vitrification materials stream (Glass, Fig. 2).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention separate the waste plastic to produce a stream of vitrification materials, as taught by Bai, and to feed at least a portions of said stream to the partial oxidation gasifier of Khan.
One of ordinary skill in the art would have been motivated to do so because such sorting can remove non-processable waste, prohibitive items, and marketable recycles from the waste stream and improve its performance during gasification, as taught by Bai ([0020] and [0003]), and because feeding the vitrification materials with plastics to the partial oxidation gasification allows for the production of a slag that encapsulates toxic components of the waste stream and which could be sold as a useful by-product (toxic elements in the inorganic matter in the solid carbonaceous plastic-containing material are captured by the noncombustible constituents in the aluminosilicate-containing material and converted into nontoxic nonleachable slag. This permits the nontoxic slag to be sold as a useful by-product; col. 5, lines 53-58), as taught by Khan.
It would have also been obvious to produce a vitrification materials stream containing one or more plastic materials at 4-50 wt%. One of ordinary skill would have been motivated to do so because this stream would be fed to the partial oxidation gasifier which Khan teaches should be supplied with a stream containing from about 20 wt% to less than 100 wt% of solid carbonaceous plastic-containing material, and such material could be supplied from either the waste plastic feedstock or the vitrification materials stream with equivalent results, as both streams end up together in the gasifier.
It is further noted that the amount of plastic in the vitrification materials stream may come from either inefficient separation in the method taught by Bai, or from the purposeful addition of plastic materials back into this stream. As the vitrification materials are ultimately mixed with a waste plastic feedstock, it would have been obvious to optimize the efficiency of the separation by routine experimentation (Bai, [0052]) to afford the desired balance of compositions of separated streams with resources put into the separation, including by allowing some plastics to pass through into the vitrification materials stream at an amount of 4 wt% to 50 wt%. It would have also been obvious to mix plastic back into the vitrification material stream to afford the desired level of plastic in the mix being fed to the partial oxidation gasifier, from about 20 wt% to less than 100 wt% of solid carbonaceous plastic-containing material, as taught by Khan.
It is noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists (see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); Titanium Metals Corp. of America v. Banner, 778 F2d 775. 227 USPQ 773 (Fed. Cir. 1985) (see MPEP 2144.05.01). Therefore, the claimed ranges of plastic materials in the vitrification stream merely represent an obvious variant and/or routine optimization of the cited prior art.
Claims 19 is rejected under 35 U.S.C. 103 as being unpatentable over Khan et al. (US 5,656,042 A) in view of Bergmann et al. (US 2012/0266532 A1), as applied to claim 1 above, and further in view of Bai (US 2013/0240647 A1) and National Geographic (“Plastic Recycling Guide”, Strange Days on Planet Earth. Retrieved from the Internet: <http://www-tc.pbs.org/strangedays/pdf/StrangeDaysSmartPlasticsGuide.pdf>, Archived 2015-02-13).
Regarding claim 19, modified Khan teaches the method of claim 1, which comprises feeding a plastic stream (scrap plastic materials which are used as feed… column 2, lines 8) and one or more vitrification materials (associated inorganic matter [column 1, line 50], which include vitrification materials such as titania, alumina, aluminum, glass and barium carbonate [column 2, lines 22-33]) to a partial oxidation gasifier (to a partial oxidation gas generator; column 2, lines 9) and partially oxidizing the plastic within said partial oxidation gasifier to produce said synthesis gas (column 1, lines 60-62).
Khan does not teach separating a mixed plastic waste into a polyethylene terephthalate (PET)-enriched plastic stream and a polyolefin-enriched PET-depleted plastic stream.
However, Bai teaches the separation of a mixed plastic into various streams (Fig. 2 and 3) including a PET-enriched plastic stream (hard plastics ([0028]; 360B Fig. 3) and a polyolefin-enriched PET-depleted stream (soft plastics ([0037]; 360D, Fig. 3) and a heavies stream comprising one or more vitrification materials (Glass; 360A Fig. 3).
Furthermore, National Geographic teaches that PET is one the most easily recycled plastics and that it can be recycled into new bottles or into polyester fibers (Plastic #1), while low density polyolefins (LDPE and PP) are not usually or easily recycled (Plastic #4 and Plastic #5).
Therefore, it would have been obvious to one of ordinary skill in the art to modify the method of Khan to first separate out the more easily recycled PET plastics into a PET-enriched stream according to the method of Bai, and to feed the polyolefin-enriched PET-depleted plastic stream and one or more vitrification materials to a partial oxidation gasifier, and to partially oxidize at least a portion of one or more polyolefins contained within said partial oxidation gasifier to produce synthesis gas, as taught by Khan. One of ordinary skill in the art would have been motivated to do so because this would allow them to funnel the more recyclable PET material to a separate recycling process while using at least part of the less-recyclable polyolefin-enriched PET-depleted stream to generate synthesis gas, a chemical feedstock.
Claim 24 is rejected under 35 U.S.C. 103 as being unpatentable over Khan et al. (US 5,656,042 A) in view of Bergmann et al. (US 2012/0266532 A1), as applied to claim 23 above, and further in view of Andrados et al. (Waste Manag. 2012, 32, 826-832).
Regarding claim 24, modified Khan teaches the method of claim 23, but does not teach any of the vitrification material stream being obtained from pyrolyzing a waste plastic in a pyrolysis reactor of a pyrolysis facility.
However, Andrados is also directed to the recycling of plastic waste streams to chemical products (abstract) and Andrados further teaches that the solids residues generated by pyrolysis of waste plastic in a pyrolysis reactor of a pyrolysis facility include ceramics and glass that would most likely be placed in a landfill (p. 831, col. 2, ¶ 1). Khan teaches that similar aluminosilicate materials can be used as vitrification materials (aluminosilicate clay materials; col. 4, lines 62-64) to produce a slag that encapsulates toxic components of the waste stream and which could be sold as a useful by-product (toxic elements in the inorganic matter in the solid carbonaceous plastic-containing material are captured by the noncombustible constituents in the aluminosilicate-containing material and converted into nontoxic nonleachable slag. This permits the nontoxic slag to be sold as a useful by-product; col. 5, lines 53-58).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention include in the vitrification material stream used in the method of modified Khan residue obtained from pyrolyzing waste plastic in a pyrolysis reactor of a pyrolysis facility, as taught by Andrados. One of ordinary skill in the art would have been motivated to do so because Khan teaches that similar aluminosilicate-containing materials can provide a source of vitrification materials that can be converted to useful by-products, and Andrados teaches that the ceramics generated in the pyrolysis reactor from a waste plastic pyrolysis facility may otherwise be destined for a landfill.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nicholas A Piro whose telephone number is (571)272-6344. The examiner can normally be reached Mon-Fri, 8:00 am-5:00 pm.
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/NICHOLAS A. PIRO/Assistant Examiner, Art Unit 1738
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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