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.
Claims 1–15 are rejected under 35 U.S.C. §103 as being unpatentable over Gephart et al. (US 2015/0080624 A1) in view of Choi et al. (US 2009/0012340 A1) and further in view of Müller (DE3146194A1).
Gephart teaches an apparatus for processing hydrocarbon materials such as waste plastics comprising a feed system for introducing hydrocarbon material, a heating system including a first screw reactor for melting the material and a second screw pyrolysis reactor for thermally decomposing the material, wherein the waste plastic is dried prior to pyrolysis (¶ [0013]), the melted waste plastic is transferred into the screw pyrolysis reactor (¶ [0013]), hydrocarbon vapor is produced and further decomposed in a downstream vessel (¶ [0015]), and the hydrocarbon vapors are separated in a plurality of condensers for product recovery (¶ [0007]).
Müller teaches a multi-stage thermal depolymerization apparatus including an extruder for melting polymeric materials (stage 1), partial thermal decomposition in the extruder (stage 2), transfer of molten/gaseous material to a downstream pyrolysis reactor (stage 3), and condensation of gaseous products (stage 4), wherein the system operates under exclusion of oxygen and employs screw-based conveying, melting, and mixing of polymeric materials.
Choi teaches a hydrocarbon thermal-cracking apparatus including a catalyst packed within a reactor tube (¶ [0015], [0063]), wherein the catalyst comprises zirconium-containing compounds and the zirconium compound may be a salt such as a sulfate (¶ [0033]), the catalyst is mixed with or supported on a carrier, preferably silicon carbide (¶ [0044]–[0045]), and the catalyst is formed into shaped bodies (e.g., rings) and packed in part or all of the cracking zone to improve cracking efficiency and heat transfer (¶ [0063], [0064]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify Gephart to incorporate Müller’s staged thermal treatment (extruder + downstream reactor) to improve depolymerization efficiency and continuous processing. It would have been further obvious to incorporate Choi’s packed zirconium-containing catalyst system (including zirconium salts such as sulfates supported on silicon carbide) into the downstream reactor of Gephart to improve hydrocarbon cracking efficiency, yield, and heat transfer.
Choi does not teach ratio of Ziconium sulfate to carbide about 2:3 to 3:2. However, Choi teaches variable catalyst composition and loading (¶ [0044]). Thus, the ratio is a result-effective variable, and optimizing zirconium sulfate-to-carbide proportions would have been obvious through routine experimentation.
Claim 2
Gephart teaches feed introduction and processing of waste plastics (¶ [0013]), and Müller teaches introducing polymeric materials in comminuted form into the extruder.
Claim 3
Gephart teaches screw-based reactors for conveying and melting (¶ [0013]), and Müller teaches screw-based conveying, mixing, and compression in extruders.
Claim 4
While not expressly disclosed, vented stuffing feed systems are well-known equivalents of screw-based feed systems such as those taught by Gephart (¶ [0013]) and Müller (extruder feed), and their use for devolatilization would have been obvious.
Claim 5
Gephart teaches screw reactors (¶ [0013]) and Müller teaches mixing, compression, and melt transport in screw devices, making use of mixing elements and seals an obvious design variation.
Claim 6
Gephart teaches multiple reactors (melting + pyrolysis) (¶ [0013]), and Müller teaches staged heating (extruder + reactor).
Claim 7
Relative chamber sizing is not explicitly disclosed but is an obvious engineering optimization of the staged system taught by Gephart and Müller.
Claim 8
Gephart teaches drying (~150–180°C), melting (~290–325°C), and pyrolysis (~450–500°C) (¶ [0013]), while Müller teaches staged temperature zones, rendering different temperature chambers obvious.
Claim 9
Gephart teaches multiple condensers for product recovery (¶ [0007]) and continuous feed processing (¶ [0013]).
Claim 10
Choi teaches packed catalyst reactors (¶ [0063]), and fixed-bed reactor configurations are conventional equivalents for such packed catalyst systems.
Claim 11
Gephart teaches downstream processing and separation of hydrocarbon vapors (¶ [0015]), and Choi teaches partial or full catalyst placement in reactor zones (¶ [0063]), suggesting splitting flows into multiple paths.
Allowable Subject Matter
Claims 12-15 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
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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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Prem C Singh can be reached at 571-273-6381. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/TAM M NGUYEN/Primary Examiner, Art Unit 1771