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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 10/23/2025 has been entered.
Response to Amendment
The examiner acknowledges Applicant’s response containing remarks and amendments to the claims, specification, and drawings.
The objections to the drawings are partially withdrawn in view of the replacement drawings and the amendments to the specification. See the objections to the drawings and the specification below. Applicant states in Remarks (pg. 3) that the specification has been amended so that “both 38 and 38A refer to feeds… while 36 refers to air or another oxidant. [The amendment] harmonizes the descriptions of FIGS 1 to 4, so that all references to forward feed correspond to step A, all references to reverse regeneration correspond to step B, and all references to reverse feed correspond to step C.” The examiner notes that additional changes are required to be consistent with the amended specification and drawings where references 38 and 36 correspond the feed flow and oxidant flow, respectively, and where forward feed, reverse regeneration, and reverse feed corresponds to cycles (A), (B), and (C), respectively.
The rejection of claim 14 under 35 USC 112(b) is withdrawn in view of the amendment.
Drawings
The replacement drawings were received on 10/23/2025. Figs 1 and 2 are acceptable. Fig. 3 is not unacceptable.
The drawings are objected to because of the following informalities.
(1) The specification, in paragraph 0055, describes that the purge cycle (P1) is arranged after the forward cycle (A) and prior to the reverse regeneration cycle (B), which is not consistent with the drawing. In Fig. 1, the references “(P2)” and “(P1)” should be switched.
(2) In Fig. 2, reference numbers for the valves do not correspond to those in Fig. 1. For example, forward feed 38 are connected to valves 52 and 54, whereas in Fig. 1 a forward flow is passed through valves 30 and 24. Furthermore, there are discrepancies with respect to the valves being used and the flow direction for the air/oxidant 36 and purge 40. Specifically, valves 26 and 32 are used for purge 40 in Fig. 2; the same valves are used for reverse feed in Fig .1. Stream 46 is an incoming purge stream in Fig. 2, whereas in Fig. 1 stream 46 is an outgoing purge stream.
(3) In Fig. 3, during cycle (A), stream 36 enters reactor 50 via valve 30 and leaves via valve 42. Since cycle (A) is a forward feed cycle, the inlet stream should be 38, not 36. Additionally, in cycles (P1), (P2), and (P3), there are only outgoing streams. Applicant is suggested to change the direction of the stream 40, which is air/oxidant.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Specification
The disclosure is objected to because of the following informalities.
(1) The specification, in paragraph 0052, states “The other valves 24, 28, 30, 34 can remain closed,” but it is unclear as to which of the cycles, (A), (B), (P1), and/or (P2), that the said closing of valves 24, 28, 30, 34 applies to. It is noted that the valves 24, 28, 30, and 34 are closed during regeneration cycle (B), which is described in paragraph 0053. Applicant is suggested to amend paragraph 0052 as follows:
[0052] The reactor member 10 operates as a cyclic fixed bed reactor with alternating flows of feed such as HC 38 in forward feed cycle (A), oxidant such as oxygen in air 36 or another oxygen-containing gas in reverse regeneration cycle (B), and optional purge fluid flows such as steam 40 in purge cycles (P1), (P2). During cycle (A), 26, 28, [[30]] 32, 34 can remain closed.
(2) The description with regard to “regeneration cycle (B)” in paragraph 0053 is inconsistent with Fig. 1, because, in Fig. 1, air or oxygen-containing gas 36 flows through valves 26 and 32 during cycle (B), not valves 30 and 24. Specifically, the air/oxygen-containing gas 36 flows sequentially through valve 26, heat exchange zone 14, reaction zone 18, heat exchange zone 16, and valve 32. Applicant is suggested to amend paragraph 0053 as follows:
[0053] Oxidation of a solid active material, and fuel combustion, are examples of the exothermic, regenerating reaction that can occur in reaction zone 18 in regeneration cycle (B). In any case, the air 36 (or other oxygen containing gas) is supplied via valve [[30]] 26, preheated in heat exchange zone [[16]] 14, exothermically reacted in reaction zone 18, and the resulting flue gas heats heat exchange zone [[14]] 16 and is exhausted via valve [[24]] 32 to flue gas line [[42]] 46. During cycle (B), the other valves [[26]] 24, 28, [[32]] 30, 34 can remain closed.
(3) The description with regard to “forward feed cycle (A)” in paragraph 0054 is inconsistent with Fig. 1, because HC 38 flows sequentially through valve 30, heat exchange zone 16, reaction zone 18, heat exchange zone 14, and valve 24. Applicant is suggested to amend paragraph 0054 as follows:
[0054] Reforming, pyrolysis, hydropyrolysis, dehydrogenation, dehydrocyclization and hydroformylation are examples of the endothermic reactions that can occur in reaction zone 18 in forward feed cycle (A). The HC 38 or other feed as appropriate is supplied via valve [[26]] 30, preheated in heat exchange zone [[14]] 16, and endothermically reacted in reaction zone 18. The resulting product is quenched in heat exchange zone [[16]] 14, and discharged via valve [[32]] 24 to product line [[44]] 42. If desired, the cycles (A) and (B) may be alternated with respective purge cycles (P1), (P2) in which an inert fluid such as steam 40 is introduced via valve [[34]] 28, purges the bed 18, and is exhausted from valve [[28]] 34 into return line 46. The purge cycles (P1), (P2) are optional, depending on the process, and can occur in the forward (in valve [[[28]] 34, out valve [[34]] 28) and/or reverse (in valve [[34]] 28, out valve [[28]] 34) flow directions. A purge fluid other than steam can be any generally inert fluid such as nitrogen or argon, or a vacuum can be applied to one or both of valves 28, 34.
(4) The description with regard to “cycle (A)” in paragraph 0055 is inconsistent with Fig. 1, because the reaction product is recovered via line 42, not 44. Applicant is suggested to amend paragraph 0054 as follows:
[0055] In cycle (A), HC 38 is flowed in the forward direction, and the high temperature in the reaction zone 18 induces an endothermic reaction such as cracking, and the reaction product is recovered via line [[44]] 42. HC 38 is flowed until the bed 12 cools by a specified amount. Then, the bed 12 is purged with steam 40 in cycle (P1). Next, in cycle (B), a flow of air 36 (and fuel if applicable) generates heat and/or regenerates the reaction zone 18. When the temperature of the bed 12 swings by a specified amount, the flow of air 36 (and fuel if applicable) is stopped, and the bed 12 is purged with steam 40 in cycle (P2). Then the process repeats and starts anew with cycle (A).
(5) The description with regard to “cycle (A)” and “cycle (B)” in paragraph 0056 is inconsistent with the description in paragraphs 0052-0054. Applicant is suggested to amend paragraph 0054 as follows:
[0056] An advantage of the RFR is that it recuperates heat in heat exchange zones 14, 16 and/or reaction zone 18, and uses that heat to supply the enthalpy for the endothermic chemical reaction. This allows more efficient use of energy than allowed by other reactors, such as a steam cracker, in which the heat in the product stream is used to boil water or oil. To accomplish heat recuperation, the prior art RFRs exchanged heat between a product stream and a regeneration stream that comprises air and flue gas recycle. Since the flue gas typically has just 1/3 the specific heat capacity of a hydrocarbon, the regeneration mass flow was about 3 times larger than the feed/product flow to achieve sufficient cooling. For example, for every reactor 10 in the forward feed conversion mode (A), three would be needed in reverse regeneration mode (B).
(6) The description with regard to “reverse regeneration cycle (B)” in paragraph 0058 is inconsistent with Fig. 2, because a reverse flow of oxidant can be initiated by opening valves 28 and 34, not 24 and 30.
Given the wide range of discrepancies discussed above, Applicant is respectfully requested to review the drawings (Figs. 1-3) and their accompanying description in the specification in their entirety and make appropriate changes.
Response to Arguments
Applicant's arguments (see Remarks) with respect to the rejection of claims1 under 35 USC 103 as being unpatentable over Henao et al. (US 2015/0065767 A1) have been fully considered but they are not persuasive.
On pages 13-14, Applicant argues that Henao fails to teach or suggest the limitations that the temperatures of the forward flow reaction product and the reverse flow reaction flow are no more than 100°C greater than the temperatures of the corresponding feeds. In response to the Office’s statement that Henao teaches using thermal mas capable of absorbing, storing, and releasing heat over a range of 50-1500°C (see Final Rejection, pg. 8) and, thus, it would have been obvious to optimize the use of thermal mass materials to maximize heat transfer between cycles and arrive at the claimed limitation, Applicant contends that the broad range of temperatures suggested by Henao does not suggest the temperature difference between products and reactants should be 100 °C or less.
In response, the examiner acknowledges that Henao does not explicitly teach that the temperature differences between the forward and reverse products and corresponding reactants is each 100°C or less. However, Henao teaches that a thermal mass located downstream of a reaction absorbs heat from the product mixture to cool the product mixture to quench the reaction, thereby obviating the need for an external quench, and to impart heat to a reverse flow feed during the second interval ([0092]). Therefore, one of ordinary skill in the art would have been motivated to find an optimal amount of heat to be removed from a reaction product and arrive at the feature, i.e., the temperatures of the forward flow reaction product and the reverse flow reaction product being no more than 100°C greater than the temperatures of the corresponding feeds. For example, one would have been motivated to transfer as much heat from the reaction product as possible since the transferred heat is subsequently used for heating a feed flow in a reverse direction. Additionally, the cited portion including the temperature range of 50-1500°C was referenced by the examiner to emphasize the roles of thermal mass over a broad range of reaction temperatures, i.e., to absorb, store, and release heat.
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 1-4, 6, 8-10, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Henao et al. (US 2015/0065767 A1, cited in IDS dated 04/16/2024).
Regarding claim 1, Henao discloses a reverse flow reaction process comprising:
a forward feed flow cycle (“a forward-flow hydrocarbon conversion step”) comprising heating and reacting a forward flow of a feed through a flow-through reactor member to produce a first reaction product ([0091]-[0092], [0151])
a reverse feed flow cycle (“a reverse-flow hydrocarbon conversion step”) comprising heating and reacting a reverse flow of the feed through the reactor member in a reverse flow direction opposite the forward feed cycle to produce a second reaction product ([0091]-[0092], [0152]); and
a regeneration cycle comprising heating and regenerating the reactor member with a flow of regenerant through the reactor member in the reverse flow direction ([0091]-[0092]).
Henao does not teach that a temperature of the first reaction product existing the reactor members(s) is no more than 100°C higher than a temperature of the forward flow of feed entering the reactor members(s), and/or a temperature of the second reaction product existing the reactor member(s) is no more than 100°C higher than a temperature of the reverse flow of feed entering the reactor member(s).
However, Henao teaches that thermal energy between steps/cycles is transferred using a thermal mass in order to preheat feed materials, wherein the thermal mass is capable of absorbing, storing, and releasing heat over a range of 50-1500°C ([0092], [0095]). Therefore, it would have been obvious for one skilled in the art to optimize the use of thermal mass materials to maximize the heat transfer between cycles and to arrive at the claimed limitation where the temperature difference between the forward flow of feed and the first reaction product and/or between the reverse flow of feed and the second reaction product is no more than 100°C. Specifically, one would have been motivated absorbing sufficient heat from the reaction product stream and transfer the absorbed heat to a reverse feed in order to increase heat efficiency. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. MPEP 2144.05 II.
Regarding claim 2, Henao discloses the process of claim 1, as discussed above. Henao further teaches that a plurality of reverse-flow reactors can be used and that the reactors may repeat the forward feed flow step, the reverse feed flow step, and the regeneration step in sequence ([0087], [0091]).
With regard to the limitation that the plurality of reverse-flow reactors are parallelly oriented, a related application, Docket No. 2013EM242/2US (US 2015/0065771 A1), which is incorporated by reference in entirety, discloses that a plurality of reverse-flow reactors can be arranged in parallel ([0129]).
Regarding claim 3, Henao discloses that the reverse flow reactors comprise a first aperture and a second opposed aperture adjacent respective first and second ends of a reactor and flow passages through the respective reactor members between the first and second opposed apertures ([0030]);
wherein the forward feed flow cycle comprises:
establishing the forward flow of the feed from a first feed conduit to the first apertures of the forward reaction set of the reactor members; passing the forward flow of the feed through the reactor members in a forward direction to form a first reaction product; and establishing a flow of the first reaction product from the second apertures of the forward reaction set of the reactor members to a first reaction product conduit ([0030];
wherein the reverse feed flow cycle comprises:
establishing the reverse flow of feed from a second feed conduit to the second apertures of the reverse reaction set of the reactor members; passing the reverse flow of feed through the reactor members in a reverse direction to form a second reaction product; and establishing a flow of the second reaction product from the first apertures of the reverse reaction set of the reactor members to a second reaction product conduit ([0030]).
Henao further teaches that the regeneration step/cycle involves: passing the regenerant mixture along the flow path within the reactor to carry out the regeneration ([0092]).
Henao does not explicitly teach that the regenerant flows in the same direction as the reverse feed flow cycle. However, since there are only two possible directions (i.e., forward flow and reverse flow) in which the regenerant can flow in the reactor, choosing either direction would have been considered obvious, in the absence of any criticality or new results.
Regarding claim 4, Henao teaches that the forward feed flow cycle, the reverse feed flow cycle, and the regeneration cycle are repeated in sequence, but does not specify the number of repetitions. Henao is thus interpreted to be open to operating the cycles a plurality of times.
Regarding claim 6, Henao teaches recuperating heat from an effluent of the regenerant and from a reverse feed flow reaction product, into a thermal mass, which transfers heat to the forward flow of the feed ([0092], [0151]). Similarly, heat recuperated from a forward feed flow reaction product is imparted to the reverse flow of regenerant and the reverse flow of the feed ([0092], [0151]).
Regarding claims 8 and 9, Henao does not teach that its process comprises: a temperature swing between cycles of no more than 50°C (claim 8) and a balanced heat flow wherein convection in the reactor member(s) in the forward feed flow cycle matches total convection in the reactor member(s) in the reverse feed flow cycle and the regeneration cycle (claim 9). However, Henao teaches that thermal energy between steps/cycles is transferred using a thermal mass in order to preheat feed materials, wherein the thermal mass is capable of absorbing, storing, and releasing heat over a range of 50-1500°C ([0092], [0095]). Therefore, it would have been obvious for one skilled in the art to optimize the process by minimizing heat loss between cycles and arrive at the claimed limitations with regard to the temperature swing between cycles and the heat balance via routine experimentation.
Regarding claim 10, Henao discloses that residence times in the reactor may be 0.01 to 20 seconds ([0085]). Henao does not explicitly teach that the residence times of the forward flow of feed and the reverse flow of feed are different. However, given the breadth of the range, it would have been obvious for one skilled in the art to select different residence times for the forward and reverse cycles by routine experimentation.
Regarding claim 16, Henao discloses that the regeneration step involves combustion of a regenerant mixture of an oxygen-containing gas (“oxidant”) and fuel ([0043], [0092]).
Regarding claim 17, Henao does not explicitly teach that the oxygen provided in the regenerant comprises no more than 5 vol% molecular oxygen. However, it is fairly known in the art that a low concentration of oxygen is used in a regeneration gas to avoid damages to the catalyst through excessive oxidation. Therefore, it would have been obvious for one skilled in the art to optimize the concentration of molecular oxygen in the regenerant and arrive at the claimed range of no more than 5 vol%, as one would be motivated to use an effective amount of oxygen without damaging the catalyst.
Regarding claim 18, Henao is directed to an oxidative dehydrogenation reaction (“oxydehydrogenation”) ([0063]).
Claims 5 and 11-15 are rejected under 35 U.S.C. 103 as being unpatentable over Henao et al. (US 2015/0065767 A1, cited in IDS dated 04/16/2024), as applied to claim 2, and further in view of Weiss et al. (US 2019/0055178 A1, cited in IDS dated 04/16/2024).
Regarding claim 5, Henao teaches the process of claim 2, as discussed above.
Henao does not teach conducting a purge cycle following each of the forward feed flow, reverse feed flow, and regeneration cycle.
However, Weiss, which is also directed to a process for the oxydehydrogenation of alkanes to olefins using a reverse flow reactor, teaches purging the reactor to remove air or hydrocarbon from the reactor between switches from regeneration flow and product formation flow ([0040], [0058]).
Therefore, before the effective filing date of the instant invention, it would have been obvious to one of ordinary skill in the art to modify Henao by conducting a purge cycle following each of the forward feed flow, reverse feed flow, and regeneration cycle, because (i) Henao and Weiss are drawn to drawn to the same type of conversion process, i.e., oxydehydrogenation in a reverse flow reactor, (ii) Weiss suggests conducting a purge step between different cycles to remove residual air or hydrocarbon from the reverse flow reactor, thereby preparing the reactor for the next step/cycle, and (iii) this involves application of a known technique to improve a known process to yield predictable results.
Regarding claim 11, Henao teaches the process of claim 2, as discussed above.
Henao further teaches that the reactors may contain catalysts having oxydehydrogenation functionality, and useful catalysts include metal oxide catalysts ([0063]-[0064)). Additionally, the regeneration step in Henao involves combustion of a regenerant mixture of an oxygen-containing gas (“oxidant”) and fuel ([0043], [0092]).
Henao does not explicitly teach that (i) the feed reaction comprises reducing an active phase of the catalyst from an oxidized state to a reduced state, and (ii) the regeneration step comprises oxidizing the active phase from the reduced state to the oxidized state.
However, Weiss, which is also directed to a process for the oxydehydrogenation of alkanes to olefins using a reverse flow reactor, teaches using a reducible, metal oxide dehydrogenation catalyst (referred to as “oxygen transfer agent” or “OTA”), wherein the catalyst releases oxygen and undergoes reduction during the reaction and becomes reoxidized during regeneration ([0006]-[0007], [0040]-[0044]).
Therefore, before the effective filing date of the instant invention, it would have been obvious to one of ordinary skill in the art to modify Henao by using a reducible, metal oxide dehydrogenation catalyst, which is expected to be reduced during the reaction step and reoxidized during the regeneration step, as taught by Weiss, because (i) Henao suggests using metal oxide catalysts, (ii) Weiss teaches effective metal oxide catalysts, which are expected to undergo reduction and oxidation during reaction and regeneration, respectively, and (iii) this involves application of a known catalyst in a known process to yield predictable results.
Regarding claim 12, Weiss teaches that useful metal oxide catalysts for the oxydehydrogenation include a transition metal oxide, e.g., manganese ([0042]; see also Henao, [0065]).
Regarding claim 13, Weiss teaches that the metal oxide catalyst may comprise an oxide of a first element selected from transition metal elements, such as manganese ([0042])). The transition metal is reversible oxidizable and reducible between reduced and oxidized states, wherein the oxidized state of the transition metal oxide is present during the reaction cycle (corresponding to the forward and reverse flow cycles in Henao) and the reduced state of the transition metal is present during the regeneration cycle. ([0006]-[0007], [0042]).
Regarding claim 14, Weiss further discloses that that the metal oxide catalyst may comprise a mixture Mn2O3 and MnTiO3 ([0076]), which corresponds to the claimed active phase and the composite phase, respectively. Weiss does not explicitly teach a support phase. However, it is generally known in the art to employ a support material to support active materials to increase surface area and physical stability. Therefore, mere addition of a support to a known catalytic material is considered prima facie obvious, in the absence of new or unexpected results.
Regarding claim 15, Weiss suggests that the catalyst may comprise a promoter, such as Na2WO4 ([0086]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JASON Y CHONG whose telephone number is (571)431-0694. The examiner can normally be reached Monday-Friday 9:00am-5:30pm.
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/JASON Y CHONG/Examiner, Art Unit 1772
/IN SUK C BULLOCK/Supervisory Patent Examiner, Art Unit 1772