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 .
Election/Restrictions
Applicant's election with traverse of the restriction requirement in the reply filed on 03/09/2026 is acknowledged. The traversal is on the ground(s) that search and examination of all the claims would not pose an undue burden on the Examiner, particularly, at least claims 21 and 25 should be grouped together with claims 1-16 because all the features of claims 21 and 25 are included in claims 1-16. This is not found persuasive because, as found in the restriction requirement, the subject matter of these claims has attained a separate status in the art in view of their different classifications, such that a search burden is necessarily present.
The requirement is still deemed proper and is therefore made FINAL.
Claims 17-25 are therefore withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim.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 03/09/2026.
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 1-16 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.
The term “low-carbon” in Claims 1 and 14 is a relative term which renders the claim indefinite. The term “low-carbon” 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. Claims 2-13, 15-16 are rejected for their dependence on Claim 1 and for further failing to remedy this indefiniteness. For purposes of examination, the examiner will interpret the limitation as requiring fuels derived from the claimed sources, i.e., from a tail gas from a pressure swing adsorption, an unpurified mixture product from an ammonia scrubber, the vaporized ammonia stream, or a combination thereof.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-3, 9-10, 12-15 is/are rejected under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by WO2022189560A1, hereinafter ‘Han’.
Regarding Claim 1, Han discloses a process for dissociating ammonia into hydrogen and nitrogen (Claim 1), comprising:
preheating a liquid ammonia feed in a first preheater to produce a preheated liquid ammonia stream while recovering heat from a dissociated hydrogen/nitrogen stream (Page 3: an ammonia feed stream is heated by heat exchange with gaseous effluent resulting from dissociation of ammonia – this is considered to take place within a unit considered a preheater);
vaporizing the preheated liquid ammonia feed to produce a vaporized ammonia stream (Page 14: the ammonia feed stream is derived from liquid ammonia such as liquid ammonia imported from storage, for instance liquid ammonia or liquid anhydrous ammonia, and which has been subjected to evaporation, e.g. in an ammonia evaporator, and optional pre-heating e.g. in a feed/effluent heat exchanger prior to said evaporation);
dissociating at least a portion of the vaporized ammonia stream to produce the dissociated hydrogen/nitrogen stream by feeding the vaporized ammonia stream to a first reactor to produce a reactor effluent (Page 10: step ii) comprises passing the ammonia feed stream to at least one ammonia pre-cracking reactor for producing a partly converted ammonia feed stream comprising ammonia, hydrogen, and nitrogen); and
feeding the reactor effluent to a radiant tube reactor provided in an ammonia dissociation furnace (Page 10: step iii) comprises passing the partly converted ammonia feed stream or the ammonia feed stream to an ammonia cracking reactor for producing an effluent gas stream comprising hydrogen and nitrogen and optionally also unconverted ammonia; the ammonia cracking reactor is suitably a fired heated reactor comprising one or more catalyst filled tubes, which are considered radiant tube reactor(s)); and
feeding a low-carbon fuel to the ammonia dissociation furnace from a tail gas from a pressure swing adsorption, an unpurified mixture product from an ammonia scrubber, the vaporized ammonia stream, or a combination thereof (Page 11: when operating with a hydrogen recovery unit having one Pressure Swing Adsorption (PSA) unit, the off-gas stream is hereby used as fuel in e.g. the fire heated reactor by mixing with a separate incoming stream of combustion air, preferably at different locations along the length of the fired reactor (fire heated reactor).
Regarding Claim 2, Han discloses dissociating the vaporized ammonia stream further comprises contacting the vaporized ammonia stream to one or more catalysts comprising a nickel-based catalyst, a ruthenium-based catalyst, or a combination thereof (Page 7: higher temperatures may in some instances still require the use of more expensive catalysts capable of operating at such temperatures, such as a nickel-based catalyst).
Regarding Claim 3, Han discloses feeding the vaporized ammonia stream to the first reactor further comprises feeding the vaporized ammonia stream to an adiabatic reactor or to an isothermal unit (Page 6: in the ammonia cracking process, either in a pre-cracking reactor or a subsequent ammonia cracking reactor, is endothermic, requiring heat for maintaining the ammonia cracking reaction ongoing and hence the temperature will decrease across the adiabatic pre-cracking reactor, herein also referred as adiabatic reactor, as the reaction is shifted to the right).
Regarding Claim 9, Han discloses providing heat to the ammonia dissociation furnace by combusting fuel (Page 11: when operating with a hydrogen recovery unit having one Pressure Swing Adsorption (PSA) unit, the off-gas stream is hereby used as fuel in e.g. the fire heated reactor by mixing with a separate incoming stream of combustion air, preferably at different locations along the length of the fired reactor (fire heated reactor)).
Regarding Claim 10, Han discloses preheating at least a portion of the fuel via one or more coils located in a convection section of the ammonia dissociation furnace (Page 26: The ammonia feed gas stream 9 is then further preheated in heat exchanging unit by e.g. a heating coil, arranged within the convection section of the fire heated reactor).
Regarding Claim 12, Han discloses vaporizing the preheated liquid ammonia feed comprises recovering heat from the dissociated hydrogen/nitrogen stream before the preheater recovers heat from the dissociated hydrogen/nitrogen stream (Fig. 1: the liquid ammonia stream 3 passes first to second feed/effluent heat exchanger 12 to become preheated stream 5, which is evaporated in evaporator 14, using cooled effluent gas stream 17, after which the cooled effluent stream 19 passes through exchanger 12 to preheat the ammonia stream).
Regarding Claim 13, Han discloses feeding the dissociated hydrogen/nitrogen stream to a purification process after the preheater has recovered heat from the dissociated hydrogen/nitrogen stream to produce a hydrogen product stream having a hydrogen concentration ranging from 75 mol % to about 99.99999 mol % (Pages 19-20: the hydrogen recovery unit comprises at least one Pressure Swing Adsorption (PSA) unit for thereby producing said hydrogen product and said off-gas stream. Hence, hydrogen purification of the effluent gas stream from the ammonia cracking reactor, e.g. fire heated reactor or electrically heated reactor, is achieved by bringing in a PSA unit the hydrogen concentration from e.g. about 70% vol. in the effluent gas stream to above 99.9% vol. in the hydrogen product).
Regarding Claim 14, Han discloses a system for dissociation of ammonia into hydrogen and nitrogen comprising:
an ammonia dissociation furnace comprising a convection section and a radiant section (Page 7: the ammonia cracking reactor is a convection heated reactor, preferably comprising one or more bayonet tubes such as an HTCR reformer i.e. Topsoe bayonet reformer, where the heat for ammonia cracking is transferred by convection along with radiation);
a preheater heat exchanger arranged to receive a liquid ammonia feed and a dissociated hydrogen/nitrogen stream, the preheater heat exchanger configured to transfer heat from the dissociated hydrogen/nitrogen stream to the liquid ammonia feed and produce a preheated ammonia stream (Page 3: an ammonia feed stream is heated by heat exchange with gaseous effluent resulting from dissociation of ammonia – this is considered to take place within a unit considered a preheater heat exchanger);
a vaporizer downstream of the preheater and configured to vaporize the preheated ammonia stream to produce a vaporized ammonia stream (Page 14: the ammonia feed stream is derived from liquid ammonia such as liquid ammonia imported from storage, for instance liquid ammonia or liquid anhydrous ammonia, and which has been subjected to evaporation, e.g. in an ammonia evaporator, and optional pre-heating e.g. in a feed/effluent heat exchanger prior to said evaporation);
a first reactor configured to receive the vaporized ammonia stream, the first reactor comprising an adiabatic reactor (Page 10: step ii) comprises passing the ammonia feed stream to at least one ammonia pre-cracking reactor for producing a partly converted ammonia feed stream comprising ammonia, hydrogen, and nitrogen; Page 6: in the ammonia cracking process, either in a pre-cracking reactor or a subsequent ammonia cracking reactor, is endothermic, requiring heat for maintaining the ammonia cracking reaction ongoing and hence the temperature will decrease across the adiabatic pre-cracking reactor, herein also referred as adiabatic reactor);
a radiant tube reactor located in the radiant section and downstream from the first reactor and configured to receive a reactor effluent from the first reactor and to output the dissociated hydrogen/nitrogen stream (Page 10: step iii) comprises passing the partly converted ammonia feed stream or the ammonia feed stream to an ammonia cracking reactor for producing an effluent gas stream comprising hydrogen and nitrogen and optionally also unconverted ammonia; the ammonia cracking reactor is suitably a fired heated reactor comprising one or more catalyst filled tubes, which are considered radiant tube reactor(s)); and
a low-carbon fuel feed to the ammonia dissociation furnace from a pressure swing adsorption, an ammonia scrubber, the vaporizer, or a combination thereof (Page 11: when operating with a hydrogen recovery unit having one Pressure Swing Adsorption (PSA) unit, the off-gas stream is hereby used as fuel in e.g. the fire heated reactor by mixing with a separate incoming stream of combustion air, preferably at different locations along the length of the fired reactor (fire heated reactor).
Regarding Claim 15, Han discloses the first reactor comprises an adiabatic reactor comprising an inlet condition temperature ranging from about 500° C. to about 750° C., and an outlet condition temperature ranging from about 300 to about 550° C (Page 6: the temperature of operation is between 500 and 600 °C, and the outlet temperature can be, for instance, 400 °C).
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.
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over WO2022189560A1, hereinafter ‘Han’, in view of US20200398240A1, hereinafter ‘Jiang’.
Regarding Claim 4, while Han discloses an ammonia dissociation furnace comprising a convection section and a radiant section, and also discloses performing heat recovery of various streams within the process, as discussed above, Han does not disclose that feeding the vaporized ammonia stream to the first reactor further comprises feeding the vaporized ammonia stream to an isothermal unit configured to recover heat form the dissociated hydrogen/nitrogen stream.
Jiang discloses an ammonia decomposition apparatus for the production of hydrogen ([0006]), including a casing, which includes a heating zone and a heat exchange zone communicated successively, a reaction section including catalysts, and a heat exchange coil, spirally wound on outer walls of the reaction zone, capable of feeding a preheated ammonia gas into the reaction zone for carrying out reaction therein ([0007]), resembling the reactor configuration of Han. A person of ordinary skill in the art would have recognized Jiang as analogous to Han, as both references are drawn to the same field of endeavor as the claimed invention, the cracking of ammonia in a catalytic cracking reactor to produce hydrogen - a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Jiang discloses the ammonia decomposition apparatus further includes a burner, disposed in the heating zone and located between an inner wall of the casing and the first reaction zone, which is used for maintaining a reaction temperature in the first reaction zone ([0010]). This reactor is considered an isothermal reaction, as the temperature in the reactor is disclosed as being maintained. By this configuration, ammonia gas is decomposed into a nitrogen-hydrogen mixture while also ensuring that ammonia gas can be heated sufficiently, the heating efficiency of the ammonia gas is increased, decomposition efficiency of the ammonia gas is improved, the residual amount of ammonia gas in the nitrogen-hydrogen mixture is reduced, and the conversion rate of ammonia gas can reach 99.9% or more ([0018]). Further, the heat exchange coil spirally wound on outer walls of the reaction zone provides a means of recovering heat form the dissociated hydrogen/nitrogen stream, thereby reducing the process heat duty by redirecting what would otherwise be waste heat.
Given this, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to substitute the adiabatic reactor of Han with an isothermal reactor as disclosed by Jiang – both types of reactors have been shown in the art to be useful in cracking of ammonia, such that the substitution of one for the other would have yielded predictable results to one of ordinary skill in the art.
Claim(s) 5-8, 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over WO2022189560A1, hereinafter ‘Han’, in view of WO2022243410A1, hereinafter ‘Panza’.
Regarding Claims 5-8, and 16, Han discloses an ammonia dissociation furnace comprising a convection section and a radiant section, and also discloses performing heat recovery of various streams within the process, as discussed above. Further, Han discloses it is known to conduct the cracking of ammonia such that waste heat is recovered for steam production, which is then used to drive rotating machines elsewhere in the plant (Page 2). Han also discloses the use of pressure swing adsorption in separation of pure hydrogen from the cracking effluent, as discussed above.
However, Han does not disclose recovering heat from a convection section of the ammonia dissociation furnace to heat a boiler feed water stream, as required by Claim 5, producing steam by recovering heat from a convection section of an ammonia dissociation furnace, as required by Claim 6, using the steam to supply heat for the vaporizing of the preheated liquid ammonia feed, as required by Claim 7, recovering heat from a convection section of the ammonia dissociation furnace to heat an ammonia distillation unit downstream of the ammonia dissociation furnace, as required by Claim 8, or a steam generation section comprising one or more coils in the convection section of the ammonia dissociation furnace configured to recover heat from the ammonia dissociation furnace, as required by Claim 16.
Panza discloses a process for producing high-purity hydrogen by subjecting an ammonia stream to a pre-heating step and a catalytic cracking step (Page 3), including the use of a plurality of catalytic tubes heated by a furnace (Page 5), and having a radiant and convective section (Page 10), resembling the same reactor configuration as the reactor of Han. A person of ordinary skill in the art would have recognized Han as analogous to Panza, as both references are drawn to the same field of endeavor as the claimed invention, the generation of hydrogen from the cracking of ammonia in a convection/radiation cracking reactor - a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Further, Panza discloses that in an embodiment of the invention, the convective section of the furnace comprises a plurality of heat exchangers (coil banks) arranged in the convective section of the furnace. Preferably at least one of said heat exchangers is a steam superheater, additionally a waste heat boiler coil and water boiling coil can also be integrated in furnace. The heat recovered in the convective section of the furnace may be used for thermal integration purposes in the process or exploited for energy production. Alternatively, heat recovery can also be accomplished downstream the furnace (Page 10). The generation of steam by this process is depicted in Fig. 1 – in the convective section, pressurized steam 29 is generated by recovery heat from the combusted gases 60. This suggests recovering heat from a convection section of the ammonia dissociation furnace to heat a boiler feed water stream and producing steam by recovering heat from a convection section of an ammonia dissociation furnace.
Further, while Panza does not explicitly disclose that said generated steam is utilized to supply heat for the vaporizing of the preheated liquid ammonia feed, as discussed above, the heat recovered in the convective section of the furnace may be used for thermal integration purposes in the process. As shown in Fig. 1, heating element 6 requires heat input and represents an energy input to the cracking process. Providing steam to this unit for the vaporizing of the preheated liquid ammonia feed would reduce the heat duty of the disclosed process by thermal integration, thereby improving the energy efficiency of the process.
Further, Panza discloses recovering heat from the combusted gas by indirectly contacting a portion of the water solution with the combusted gas and feeding said portion of water solution after heat recovery to the distillation step to provide distillation heat. Advantageously, thermal integration between the distillation step and the ammonia catalytic cracking step can be realized and the energy consumption of the process can be reduced (Page 8). This suggests that heat recovered by the coil banks as described above may be utilized to heat an ammonia distillation unit downstream of the ammonia dissociation furnace.
It is clear from the above that the heat integration scheme of Panza, including recovering heat from a convection section of the ammonia dissociation furnace to heat a boiler feed water stream, producing steam by recovering heat from a convection section of an ammonia dissociation furnace, using said steam to supply heat for the vaporizing of the preheated liquid ammonia feed, recovering heat from a convection section of the ammonia dissociation furnace to heat an ammonia distillation unit downstream of the ammonia dissociation furnace, and a steam generation section comprising one or more coils in the convection section of the ammonia dissociation furnace configured to recover heat from the ammonia dissociation furnace are all features known in the art of ammonia cracking that allow for efficient thermal integration across the process, reducing thermal waste and improving process efficiency. Accordingly, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to modify the process of Han to include these features, as such a modification would predictably reduce the heat duty of the process, thereby increasing process efficiency.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over WO2022189560A1, hereinafter ‘Han’, in view of US20160017802A1, hereinafter ‘Saloway’.
Regarding Claim 11, while Han discloses that decomposed ammonia can be fed to a gas turbine, Han does not disclose feeding a gas turbine exhaust to the ammonia dissociation furnace to supply combustion air to one or more burners of the ammonia dissociation furnace.
Saloway discloses a hydrogen production process and apparatus using a combined stream of gas turbine exhaust from a gas turbine and combustion air from a forced draft fan as combustion oxidant in a steam reforming fired furnace to produce a hydrogen-comprising stream (Abstract). A person of ordinary skill in the art would have recognized Saloway as analogous to Han, as both references are drawn to the same field of endeavor as the claimed invention, reforming or cracking a reformate to produce a hydrogen-containing stream – a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212. Particularly, while the disclosure of Saloway is not particularly drawn to the reforming/cracking of ammonia, its disclosure is relevant to the process of Han in its teachings regarding the configuration of a general fired reformer and the optimization thereof.
Saloway discloses forming a first quantity of a blended oxidant stream comprising gas turbine exhaust, and combusting a first quantity of a fuel stream with at least a portion of the first quantity of the blended oxidant stream comprising gas turbine exhaust in the reformer furnace external to a plurality of catalyst-containing reformer tubes under conditions effective to combust the first quantity of the fuel stream to form a first quantity of a combustion product gas stream and generate heat to supply energy for reacting the first quantity of the reformer feed gas stream inside the plurality of catalyst-containing reformer tubes ([0080]-[0084]). By this, the turbine produces energy that may be used for on-site electrical power needs in lieu of power from the local electrical power grid ([0001]), thereby improving the energy efficiency of the process.
Accordingly, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to utilize a turbine exhaust to provide burner air to the fired furnace of Han. As shown by Saloway, such a source of combustion air is known in the art for reforming processes and would predictably reduce the energy duty for the process, thereby improving process efficiency.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LOGAN LACLAIR whose telephone number is (571)272-1815. The examiner can normally be reached M-F, 7:30-5:30 PST.
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LOGAN LACLAIR
Examiner
Art Unit 1736
/L.E.L./Examiner, Art Unit 1736
/ANTHONY J ZIMMER/Supervisory Patent Examiner, Art Unit 1736
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