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 .
Status of the Claims
This is a final Office action in response to Applicant’s arguments and amendments filed on 04/24/2026. Claims 1-20 and 23-26 are pending in the current Office action. Claims 1 and 25 were amended by Applicant.
Status of the Rejection
The rejection of claim 25 under 35 U.S.C. § 112(b) is withdrawn in view of Applicant’s amendments.
The rejections of claims 1-20 and 23-26 under 35 U.S.C. § 103 are withdrawn in view of Applicant’s amendments.
New rejections of claims 1-20 and 23-26 are necessitated by Applicant’s amendments.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-6, 15-20, and 24-26 are rejected under 35 U.S.C. 103 as being unpatentable over Xia et al. (“Hydrogen extraction characteristics of high-temperature proton conductor ceramics for hydrogen isotopes purification and recovery” Fusion Engineering and Design 89 (2014) 1500–1504) in view of Lozada (WO 2017/017433 A2) and as evidenced by, in the case of claim 20, Sala (US Pat. Pub. 2017/0016124 A1).
Regarding claim 1, Xia teaches a system for separation of hydrogen isotopes from one another (title), the system comprising:
a separation device (“electrochemical hydrogen pump” abstract and Fig. 2, annotated below), the separation device including:
a feed chamber (the interior of the ceramic tube, see § 2.2 and annotated Fig. 2), the feed chamber comprising a sample comprising a first hydrogen isotope (“He + (500-1500) ppm H2” Fig. 2), the sample being free of water (“Dry H2” Fig. 3, 6, 9 insets);
a product chamber (the space between the ceramic tube and the quartz tube, see annotated Fig. 2); and
a separation membrane forming a gas-tight seal between the feed chamber and the product chamber (“test ceramic tube” § 2.2 and Fig. 2),
the separation membrane including a hydrogen ion conductive layer (“CaZr0.9In0.1O3−α ceramic tube as the solid electrolyte proton conductor” p. 1501 bridging para. and Fig. 2),
the hydrogen ion conductive layer comprising a hydrogen ion conductive ceramic (“CaZr0.9In0.1O3−α ceramic tube as the solid electrolyte proton conductor” p. 1501 bridging para. and Fig. 2),
the separation membrane having a first side and an opposite second side, the first side facing the feed chamber and the second side facing the product chamber (see Fig. 2);
an electric circuit in electrical communication with the separation membrane (“Potentiostate [sic]” Fig. 2) and configured to apply a voltage between the first side and the second side of the separation membrane (“A voltage was applied between 0 and 3.5 V by a potentiostat.” § 2.2); and
a heater (“Electric Furnace” Fig. 2) configured to maintain the separation membrane at a temperature from 200 °C to 600 °C (“The proton-conducting ceramic tube specimen was heated by a dual stage electric furnace,” § 2.2 and see below).
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Annotated Xia Fig. 2
Xia does not explicitly teach the sample comprises a second hydrogen isotope.
However, Xia teaches that the apparatus is intended to recover tritium i.e., a second hydrogen isotope, from a hydrogen source comprising multiple hydrogen isotopes (p. 1501 col. 1 middle para.).
As Xia teaches a system for electrochemically purifying hydrogen isotopes, Xia is analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the system of Xia such that the feed chamber comprises a second hydrogen isotope e.g., tritium. A person having ordinary skill in the art would have been motivated to make this modification because Xia explicitly suggests using a sample comprising tritium and other hydrogen isotopes.
The limitation “a heater configured to maintain the separation membrane at a temperature from 200 °C to 600 °C”, as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case, Xia teaches the heater is configured to heat the separation membrane (§ 2.2.), and, as acknowledged by Applicant (see Remarks filed 04/24/2026 para. bridging p. 6-7), further teaches the system is operated at a temperature between about 650 and 800 °C (“923 to 1073 K” § 2.2), temperatures slightly higher than the upper bound of the claimed range.
As the heater of Xia is capable of heating the membrane to temperatures slightly higher than the claimed range, it is considered that the heater is also necessarily capable of heating the membrane to temperatures within the claimed range. The system of Xia therefore reads on the limitation “a heater configured to maintain the separation membrane at a temperature from 200 °C to 600 °C” as currently drafted.
Xia does not teach the separation membrane includes a hydrogen isotope selective layer, the hydrogen isotope selective layer comprising a crystalline material.
However, Lozada teaches a separation membrane for separation of hydrogen isotopes from one another (abstract), the separation membrane including a hydrogen isotope selective layer (“a monolith of a 2D material” p. 12 lines 21-27) and a hydrogen ion conductive layer (“an ionomer coating” p. 12 lines 21-27), the hydrogen isotope selective layer comprising a crystalline material (“crystalline sheets of graphene and hBN monolayers” p. 19 lines 18-21 and see p. 19 lines 8-17), wherein the inclusion of the hydrogen isotope selective layer provides the predictable benefit of allowing the separation membrane to be made thinner and lighter (“One benefit of our approach is that this allows the possibility of decreasing thickness of existing proton membranes (which is currently quite a difficult problem) by stopping permeation of other species even using the thinnest possible membranes. We can thus produce light, cost effective membranes.” p. 19 lines 25-29).
As Lozada teaches a system for separating hydrogen isotopes comprising a separation membrane in communication with an electric circuit, Lozada is analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the separation membrane of Xia by adding a hydrogen isotope selective layer comprising a crystalline material (i.e., graphene, hBN, MoS, or WS2), as taught by Lozada. A person having ordinary skill in the art would have been motivated to make this modification to achieve the predictable benefit of reducing the thickness and weight of the membrane, as taught by Lozada. Furthermore, combining prior art elements according to known methods to yield predictable results establishes a prima facie case of obviousness (MPEP § 2143(I)(A)).
Regarding claim 2, modified Xia further teaches, via Lozada, the hydrogen isotope selective layer comprises from 1 to about 5 atomic layers of the crystalline material (“The material is a monolayer (for graphene and hBN this means one atomic layer; in the case of other 2D materials such as MoS2 etc. this means one molecular layer which actually comprises three atomic layers due to the crystal structure). However, in certain cases a few layers i.e. 2 to 5 layers of the 2D material are permitted.” p. 19 lines 8-17).
Regarding claim 3, modified Xia further teaches, via Lozada, the atomic layers of the hydrogen isotope selective layer comprise atoms in a hexagonal pattern (“A single piece of graphene or hBN is preferred.” p. 19 lines 8-17).
Regarding claim 4, modified Xia teaches the limitations of claim 1, as described above. Modified Xia further teaches, via Lozada, the crystalline material comprises graphene, hexagonal boron nitride, or a transition metal chalcogenide (“a 2-D material selected from graphene, hBN, MoS2 and WS2” p. 9 lines 15-25, see also p. 19 lines 8-17).
Regarding claim 5, modified Xia teaches the limitations of claim 1, as described above. Xia further teaches the hydrogen ion conductive layer comprises a perovskite type ceramic (“CaZr0.9In0.1O3−α (effective electrode area: 160 cm2) was developed because of its high chemical stability, mechanical strength, and durability in a series of perovskite-type proton conductors.” abstract).
Regarding claims 6 and 15, modified Xia teaches the limitations of claim 5. Xia further teaches the perovskite type ceramic comprises CaZrO3 (“CaZr0.9In0.1O3−α” abstract i.e., indium doped CaZrO3).
Regarding claim 16, modified Xia teaches the limitations of claim 1, as described above. Modified Xia does not teach a second separation membrane forming a gas-tight seal between the product chamber and a third chamber, a first side of the second separation membrane facing the product chamber and a second side of the second separation membrane facing the third chamber.
However, Lozada further teaches that several stages of isotope enrichment can be arranged in series to provide a desired level of isotope enrichment (p. 48 lines 21-30).
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the system of Xia, by adding a second separation membrane forming a gas-tight seal between the product chamber and a third chamber, a first side of the second separation membrane facing the product chamber and a second side of the second separation membrane facing the third chamber. A person having ordinary skill in the art would have been motivated to make this modification to provide a second enrichment stage, thereby enhancing the final level of isotope enrichment, as taught by Lozada. Furthermore, duplication of parts (i.e., the separation membrane), absent evidence of a new and unexpected result, establishes a prima facie case of obviousness (MPEP § 2144.04(VI)(B)).
Regarding claim 17, modified Xia teaches the limitations of claim 1, as described above. Xia further teaches a gas flow line to the feed chamber (“H2 balanced with He was supplied to the anode of hydrogen pump” § 2.2 and see annotated Fig. 2).
Regarding claim 18, modified Xia teaches the limitations of claim 1, as described above. Modified Xia further teaches, via Lozada, the hydrogen isotope selective layer further comprises a metal selected from Groups 8 to 10 of the periodic table (“2-D material selected from graphene, hBN, MoS2 and WS2 which has been decorated with a discontinuous film formed from one or more transition metals selected from groups 8 to 10 of the periodic table,” p. 9 lines 15-25, see also p. 19 lines 1-3 and p. 40 lines 1-13).
Regarding claim 19, modified Xia further teaches, via Lozada, the metal is present in a discontinuous fashion on a surface of the hydrogen isotope selective layer (“2-D material selected from graphene, hBN, MoS2 and WS2 which has been decorated with a discontinuous film formed from one or more transition metals selected from groups 8 to 10 of the periodic table,” p. 9 lines 15-25, emphasis added, see also p. 17 lines 9-15).
Regarding claim 20, Modified Xia teaches the limitations of claim 1, as described above. Modified Xia further teaches, via Lozada, the crystalline material comprises graphene (“A single piece of graphene or hBN is preferred.” p. 19 lines 8-17), said graphene serving as part of an electrode (see below).
Regarding the limitation “said graphene serving as part of the electrode”, Sala teaches that a graphene layer in contact with a current collector/electrode serves as part of the electrode “the porous electronic conducting cathode is produced using carbonaceous compounds, such as graphene,” (para. 20). Therefore, as the structure of Xia (and modified Xia) comprises current collectors/electrodes (“Pt electrode” Fig. 2) on both sides of the membrane, the graphene layer in modified Xia will necessarily serve a part of the electrode. I.e., regardless of which side of the membrane the hydrogen isotope selective layer is added to, it will be in electrical communication with the Pt electrodes/current collectors.
Regarding claim 23, modified Xia teaches the limitations of claim 1, as described above.
Modified Xia does not explicitly teach the hydrogen ion conductive layer contacts the feed chamber.
However, Lozada further teaches the hydrogen isotope selective layer is arranged on the side of the membrane contacting the product chamber (e.g., Fig. 10a), i.e., such that the hydrogen ion conductive layer contacts the feed chamber.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application, when modifying the membrane of Xia to comprise the hydrogen isotope selective layer as taught by Lozada, to do so such that the hydrogen ion conductive layer is in contact with the feed chamber. A person having ordinary skill in the art would have been motivated to make the modification in this way because Lozada teaches the membrane in this arrangement. Furthermore, combining prior art elements according to known methods to yield predictable results establishes a prima facie case of obviousness (MPEP § 2143(I)(A)).
Regarding claim 24, modified Xia teaches the limitations of claim 1, as described above.
Modified Xia further teaches, via Lozada, the hydrogen isotope selective layer and the hydrogen ion conductive layer are adjacent (“an ionomer coating provided on at least one side of the 2D material” p. 12 lines 20-26).
Regarding claim 25, for the purposes of compact prosecution, claim 25 has been interpreted as depending from claim 18.
Modified Xia teaches the limitations of claim 18, as described above.
Modified Xia further teaches, via Lozada, the metal is in the form of nano-sized dots (“Pt nanoparticles were deposited onto them by evaporating a discontinuous layer of Pt (nominally, 2 nm)” § 2.3., emphasis added).
Regarding claim 26, modified Xia teaches the limitations of claim 1, as described above. Xia further teaches the sample is a gas sample (“H2 balanced with He was supplied to the anode of hydrogen pump and pure He gas fed to the cathode to sweep the permeated gas controlled by mass flow controllers (MFC).” § 2.2.).
Claims 7-14 are rejected under 35 U.S.C. 103 as being unpatentable over Xia in view of Lozada, as applied to claim 5, and further in view of Elangovan (US Pat. Pub. 2008/0032140 A1).
Regarding claim 7, modified Xia teaches the limitations of claim 5, as described above.
Modified Xia does not teach the perovskite type ceramic has the composition as follows:
A1-x-αPxB1-yQyO3-δ in which:
A is a bivalent cation,
P is an A-site dopant,
B is a tetravalent cation,
Q is a B-site dopant,
α represents the A-site non-stoichiometry (deficiency), and
δ is an oxygen deficiency.
Xia instead teaches the perovskite type ceramic has the composition: A1B1-yQyO3-δ i.e., Xia does not teach an A-site dopant.
However, Elangovan teaches perovskite-type ceramic membranes for use as a hydrogen ion conducting layer in an electrochemical cell (para. 3) that provide superior resistance to degradation by carbon dioxide (para. 10), the perovskite-type ceramics having the composition as follows:
A1-x-αPxB1-yQyO3-δ (“perovskite of the general composition A1-x-αPxB1-yQyO3-δ …” para. 26) in which:
A is a bivalent cation (“A is a bivalent cation” id.),
P is an A-site dopant (“P is an A-site dopant” id.),
B is a tetravalent cation (“B is a tetravalent cation” id.),
Q is a B-site dopant (“Q is a B-site dopant” id.),
α represents the A-site non-stoichiometry (deficiency) (“α represents the A-site non-stoichiometry (deficiency)” id.), and
δ is an oxygen deficiency (“δ is an oxygen deficiency” id.).
As Elangovan teaches a ceramic membrane for use as a hydrogen ion conducting layer in an electrochemical cell, Elangovan is analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the membrane of Xia, such that the perovskite-type ceramic of the hydrogen ion conductive layer has the composition A1-x-αPxB1-yQyO3-δ i.e., by adding an A-site dopant, as taught by Elangovan. A person having ordinary skill in the art would have been motivated to make this modification to achieve the predictable benefit of stabilizing the ceramic to reaction with carbon dioxide, as taught by Elangovan. Furthermore, combining prior art elements according to known methods (i.e., adding an A-site dopant to the perovskite of Xia) to yield predictable results (improving the stability of the perovskite) establishes a prima facie case of obviousness (MPEP § 2143(I)(A)). Furthermore, simple substitution of one known element for another (i.e., using the perovskite of Elangovan in place of the perovskite of Xia) to achieve predictable results (forming a hydrogen ion transfer membrane) establishes a prima facie case of obviousness (MPEP § 2143(I)(B)). Furthermore, use of a material known in the art as suitable for a purpose (i.e., the perovskites of Elangovan as a hydrogen ion conductor in a separation membrane) establishes a prima facie case of obviousness (MPEP § 2144.07).
Regarding claim 8, Xia further teaches A is Ca (“CaZr0.9In0.1O3−α” abstract). Modified Xia further teaches, via Elangovan, P is a cation (“P is an A-site dopant, which may be a cation such as Pr, Sm, Er or other cations belonging to the lanthanide series.” para. 26).
Regarding claims 9-10, modified Xia further teaches, via Elangovan, P belongs to the lanthanide series (claim 9) and is Pr, Sm, or Er (claim 10) (“P is an A-site dopant, which may be a cation such as Pr, Sm, Er or other cations belonging to the lanthanide series.” para. 26).
Regarding claims 11-12, modified Xia teaches the limitations of claim 7, as described above.
Xia further teaches B is an element in Group IV of the periodic table (claim 11), wherein B is Zr, (claim 12) (“CaZr0.9In0.1O3−α” abstract).
Regarding claims 13-14, modified Xia teaches the limitations of claim 7, as described above.
Modified Xia does not teach Q is an element in group III of the periodic table or an element in the lanthanide series of the periodic table (claim 13), wherein Q is Sc, Y, Eu, Nd, Gd, or Yb (claim 14).
However, Elangovan further teaches Q is an element in Group III of the periodic table or an element in the lanthanide series of the periodic table (claim 13), wherein Q is Sc, Y, Eu, Nd, Gd, or Yb (claim 14) (“Q is a B-site dopant which may be either an element in Group III of the period table (e.g. Sc, Y) or another element (other than B) in the lanthanide series of the periodic table (e.g. Eu, Nd, Gd, Yb)” para. 26).
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the perovskite of Xia such that Q is an element in the lanthanide series of the period table (claim 13), wherein Q is Sc, Y, Eu, Nd, Gd, or Yb (claim 14), as taught by Elangovan. A person having ordinary skill in the art would have been motivated to make this modification to achieve the predictable benefit of stabilizing the ceramic to reaction with carbon dioxide, as taught by Elangovan. Furthermore, simple substitution of one known element for another (i.e., using Sc, Y, Eu, Nd, Gd, or Yb in place of In as Q in the perovskite of Xia) to achieve predictable results (forming a hydrogen ion transfer membrane) establishes a prima facie case of obviousness (MPEP § 2143(I)(B)). Furthermore, use of a material known in the art as suitable for a purpose (i.e., the perovskites of Elangovan as a hydrogen ion conductor in a separation membrane) establishes a prima facie case of obviousness (MPEP § 2144.07).
Response to Arguments
Applicant’s arguments, see Remarks p. 6, filed 04/24/2026, regarding the rejection of claim 25 under 35 U.S.C. § 112(b) have been fully considered and are persuasive. The rejection of claim 25 under 35 U.S.C. § 112(b) has been withdrawn.
Applicant’s arguments, see Remarks p. 6-7, filed 04/24/2026, regarding the rejections under 35 U.S.C. § 103 over modified Xia have been fully considered, but they are not persuasive.
Applicant’s Argument #1
Applicant argues on p. 6-7 that Xia teaches an electric heater configured to maintain the separation membrane at a temperature between 650 and 800 °C (923 to 1023 K), which is patentably distinct from the limitation “a heater configured to maintain the separation membrane at a temperature from 200 °C to 600 °C” as recited in amended claim 1.
Examiner’s Response #1
Examiner respectfully disagrees. At issue Xia reads on the limitation “a heater configured to maintain the separation membrane at a temperature from 200 °C to 600 °C” as recited in amended claim 1.
In the instant case, the claim in question is an apparatus claim. The broadest reasonable interpretation of an apparatus claim limited by its function is an apparatus capable of performing the recited function (MPEP § 2114).
As acknowledged by Applicant, the heater of Xia is configured to maintain the separation membrane at a temperature of between 650 and 800 °C. As the heater of Xia is an electric heater, it is capable of heating to temperatures lower than its maximum temperature by the application of a reduced current and/or intermittent application of heating. The heater of Xia is therefore of heating the separation membrane to temperatures below 800 °C, including values with the claimed range of 200 to 600 °C. Thus, under the broadest reasonable interpretation, Xia reads on the limitation “a heater configured to maintain the separation membrane at a temperature from 200 °C to 600 °C” as recited in amended claim 1.
Applicant’s argument is therefore not persuasive.
Applicant’s argument #2
Applicant argues on p. 7 that a person having ordinary skill in the art would not have been motivated to modify the system of Xia such that the heater is configured to maintain the separation membrane at a temperature between 200 and 600 °C. Specifically, Applicant argues that because Xia teaches 750 °C (1023 K) as providing hydrogen production, Xia teaches away from using lower temperatures in the system.
Examiner’s Response #2
As discussed in Examiner’s Response #1, above, Xia is considered to teach the limitation in question. Applicant’s argument is therefore considered moot, as no modification of Xia is required to read on the limitation in question.
However, in the interest of compact prosecution, it is noted that a teaching of an optimal or preferred value is not considered a teaching away from other values known to be suitable in the art (MPEP § 2123).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALEXANDER R PARENT whose telephone number is (571)270-0948. The examiner can normally be reached M-F 11:00 AM - 6 PM EST.
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/ALEXANDER R. PARENT/ Examiner, Art Unit 1795
/LUAN V VAN/ Supervisory Patent Examiner, Art Unit 1795
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