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 .
Information Disclosure Statement
The information disclosure statements (IDS) submitted are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
Response to Amendment
The amendments filed April 23, 2026 have been entered. Accordingly, claims 13-17 and 19-24 are currently pending.
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 22-24 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.
In re claim 22, the phrase "a fourth line the second mixture" renders the claim indefinite because it is unclear whether the fourth line is the second mixture, a structure for the second mixture, or a different relationship between the fourth line and the second mixture. For purposes of examination: in order to expedite prosecution, this phrase/term is interpreted as “a fourth line to send the second mixture…”.
Claims 23-24 are rejected at least by virtue of its dependency.
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 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.
Claims 13-17 and 19-22 and 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nelson (US3398545) in view of Roldan et al (US20050091991A1).
In re Claim 13, Nelson discloses A process for the liquefaction of hydrogen (Fig. 1-4) integrated with the cryogenic separation of a first mixture of hydrogen and of another component (2),
wherein:
i) cooling the first mixture (2) in an auxiliary heat exchanger (Fig. 2 and 3: heat exchanger 12 to 74) down to at least 120K (cool stream 76 down to -292 F, i.e. 93.15 K),
the cooled first mixture is separated by partial condensation (78 and 82) and/or by distillation and/or by stripping at a temperature below 120K in order to produce a flow rich in hydrogen (80) containing at least one impurity at between 20 and 30 bar (The first vapour, leaving the top of separator 40, passes through conduit 44 to a compressor 46 where it is compressed to high pressure (approximately 435 psia, i.e., 30 bar) and
the hydrogen-rich flow (80 becomes 88) is purified at a cryogenic temperature of at most 103K (Col 4:70-Col 5:5) in order to reduce its content of the at least one impurity in order to form a hydrogen-rich gas (Col 4:70-Col 5:5: nitrogen is reduced to form a hydrogen rich gas);
ii) sending the hydrogen-rich gas (88 which becomes 92) originating from the apparatus for separation by distillation and/or stripping and/or partial condensation (78 and 82), to a hydrogen liquefier (6), without having heated the hydrogen-rich gas to a temperature above 0 C (See Col 5:1-7), wherein the hydrogen-rich gas exiting from the separation apparatus at the temperature of at most 103K containing at least 99.9 mol% of hydrogen and at a pressure between 20 and 30 bar (88 > 92).
However, Nelson does not explicitly teach, iii) cooling the hydrogen-rich gas from the temperature of at most 103K and at the pressure between 20 and 30 bar in a first heat exchanger of the liquefier; iv) cooling a second hydrogen-rich flow in a second heat exchanger of the liquefier from a temperature of greater than 103K down to the temperature of the hydrogen-rich gas to form a cooled flow; and wherein the cooled flow is subsequently cooled in the second heat exchanger, the hydrogen-rich gas is mixed with the cooled second hydrogen-rich flow having the same pressure and composition as the hydrogen-rich gas and cooled in the second heat exchanger down to the temperature of the hydrogen-rich gas in order to form a second mixture, and the second mixture is liquefied either in the first heat exchanger or after cooling in the first heat exchanger in order to form liquid hydrogen.
On the other hand, Roldan teaches iii) cooling the hydrogen-rich gas (114) from the temperature of at most 103K and at the pressure between 20 and 30 bar ([0037]: at the designated temperature and pressure) in a first heat exchanger (1501-10) of the liquefier (Fig. 2 corresponding to Nelson 6);
iv) cooling a hydrogen-rich flow (110) in a second heat exchanger (130) of the liquefier (Fig. 2 corresponding to Nelson 6) from a temperature of greater than 103K to form a cooled flow (stream leaving heat exchanger 130); and
wherein the cooled flow (stream leaving heat exchanger 130) is subsequently cooled in the second heat exchanger (130),
the hydrogen-rich gas (114) is mixed with the hydrogen-rich flow (110) having substantially the same pressure and composition as the hydrogen-rich gas and cooled in the second heat exchanger down to the temperature of the hydrogen-rich gas (See [0036]: where the gas is hydrogen and adjusted to be the same temperature and pressure) in order to form a second mixture (stream after flow 120), and
the second mixture (stream after flow 120) is liquefied after cooling in the first heat exchanger (1501-10) in order to form liquid hydrogen ([0037]: cooled to form liquified gas).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have taken the teachings of Nelson and to have modified them by cooling the hydrogen-rich gas from the temperature of at most 103K and at the pressure between 20 and 30 bar in a first heat exchanger of the liquefier; iv) cooling a hydrogen-rich flow in a second heat exchanger of the liquefier from a temperature of greater than 103K to form a cooled flow; and wherein the cooled flow is subsequently cooled in the second heat exchanger, the hydrogen-rich gas is mixed with the hydrogen-rich flow having substantially the same pressure and composition as the hydrogen-rich gas and cooled in the second heat exchanger down to the temperature of the hydrogen-rich gas in order to form a second mixture, and the second mixture is liquefied after cooling in the first heat exchanger in order to form liquid hydrogen, in order to for the hydrogen gas to condense and remain in liquid form (See Roldan [0045]), without yielding unpredictable results.
In re Claim 14, Modified Nelson teaches wherein the hydrogen-rich gas (Nelson 88) is purified by adsorption (Nelson 90) in order to remove the at least one impurity nitrogen (Nelson Col 5:1-2: at least the impurity nitrogen is removed).
In re Claim 15, Modified Nelson teaches wherein the first mixture (Nelson 2) comprises, as main components, hydrogen and carbon monoxide and possibly methane and/or nitrogen (Nelson comprise hydrogen, carbon monoxide and nitrogen, methane, and constituents heavier than butane).
In re Claim 16, Modified Nelson teaches wherein the hydrogen-rich gas (Nelson 88) is withdrawn a phase separator (Nelson 86), said separator (Nelson 86) operating at between 20 and 30 bar abs (See Nelson Col 8:15-25).
In re Claim 17, Modified Nelson teaches wherein the process is kept cold at least partially by a refrigeration cycle (Roldan 140), the fluid (Roldan 154) of the cycle (Roldan 140) being heated in the first heat exchanger (Roldan 1501-10).
In re Claim 18, Modified Nelson teaches wherein the liquefied hydrogen is stored in a storage tank (Nelson Fig. 1: liquid hydrogen from liquefier 6 goes to storage), the boil-off gas ([0105]: gas from storage tank 170) of which is heated in the first (Roldan 1501-10).
In re Claim 19, Modified Nelson teaches wherein the hydrogen-rich gas (Roldan 110) is liquefied in the first heat exchanger (Roldan 1501-10) and the first mixture (Nelson 2) is cooled (cooled via Roldan 1501-10).
In re Claim 20, Modified Nelson teaches wherein the hydrogen-rich flow (Roldan 114) is cooled in the second heat exchanger (Roldan 130) from a temperature above 0°C (See [0114]).
In re Claim 21, Modified Nelson teaches wherein the hydrogen-rich flow (Roldan 110) is cooled in the second heat exchanger (Roldan 130) and subsequently is mixed with the hydrogen-rich gas (Roldan 110)|(See Roldan Fig. 8).
In re Claim 22, Nelson discloses a separation apparatus (4) configured to separate a mixed fluid (2) using a means selected from the group consisting of distillation, stripping, partial condensation, and combinations thereof (78 and 82);
a first fluid line configured to send the hydrogen-rich gas (92) originating from the separation apparatus (4) at a temperature of at most 103K containing at least 99.9 mol% of hydrogen and at a pressure between 20 and 30 bar (See [0036-0037]) to the hydrogen liquefier (6), without having heated the hydrogen-rich gas to a temperature above 0°C (the gas is not heated see Fig. 3);
a second fluid line configured to send the hydrogen-rich gas to be cooled from the temperature of at most 103K and at the pressure between 20 and 30 bar (line of 92)
However, Nelson does not explicitly teach, a first heat exchanger and a second heat exchanger; a third fluid line to send a hydrogen-rich flow to be cooled in the second heat exchanger; a fluid junction configured to mix the hydrogen-rich gas with the hydrogen-rich flow cooled in the second heat exchanger and having substantially the same pressure, temperature and composition as the hydrogen-rich gas in order to form a second mixture; and a fourth line to send the second mixture to be liquefied in the first heat exchanger or afte--r cooling in the first heat exchanger to be liquefied in order to form liquid hydrogen.
On the other hand, Roldan teaches the first heat exchanger (1501-9);
a second heat exchanger (130);
a third fluid line to send a hydrogen-rich flow to be cooled in the second heat exchanger (120);
a fluid junction configured to mix (junction after valve 112) the hydrogen-rich gas (114) with the hydrogen-rich flow (110) cooled in the second heat exchanger (130) and having substantially the same pressure, temperature and composition as the hydrogen-rich gas in order to form a second mixture (See [0036]: where the gas is hydrogen and adjusted to be the same temperature and pressure); and
a fourth line to send the second mixture to be liquefied in the first heat exchanger (1501-9) to be liquefied in order to form liquid hydrogen (See Roldan 160 containing liquid hydrogen).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have taken the teachings of Nelson and to have modified them by having a second heat exchanger; a third fluid line to send a hydrogen-rich flow to be cooled in the second heat exchanger; a fluid junction configured to mix the hydrogen-rich gas with the hydrogen-rich flow cooled in the second heat exchanger and having substantially the same pressure, temperature and composition as the hydrogen-rich gas in order to form a second mixture; and a fourth line to send the second mixture to be liquefied in the first heat exchanger or after cooling in the first heat exchanger to be liquefied, in order to for the hydrogen gas to condense and remain in liquid form (See Roldan [0045]), without yielding unpredictable results.
In re Claim 24, Modified Nelson teaches further comprising a refrigeration cycle (Roldan 140) using helium (Roldan [0050]: helium used) in order to cool and optionally to liquefy the second mixture1.
Claim 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nelson (US3398545) as modified by Roldan et al (US20050091991A1) further in view of Cardella (US 20180347897 A1).
In re Claim 23, Modified Nelson teaches wherein the first exchanger (Roldan 1501-9) is located in a first thermally insulated chamber (Roldan 170) and
the second exchanger (130),
the point where the hydrogen-rich gas (Roldan 114) and
the hydrogen-rich flow (Roldan 110) mix being located outside the first and second chambers (See Roldan Fig. 8 mixed outside insulation).
However, Modified Nelson does not explicitly teach, is located in a second thermally insulated chamber.
On the other hand, Cardella teaches a heat exchanger located in a second thermally insulated chamber (78).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have taken the teachings of modified Nelson and to have modified them by having is located in a second thermally insulated chamber, in order to have consistent temperature cooling and control of the lowering temperature (See Cardella [0114]), without yielding unpredictable results.
Response to Arguments
The Remarks of April 23, 2026, have been fully considered but are not persuasive for the reasons below.
Applicant argues
On Page 10¶4-Page 12 of the Remarks, that the examiner has not shown that claims 13 and 22 are obvious over Nelson in view of Roldan because there is allegedly no basis in the prior art for the limitations required by the claims. Applicant appears to suggest that one of ordinary skill in the art would not recognize from the teaching of Roldan that the claimed heat exchanger and mixing configuration. It is further suggested by Applicant that Roldan does not provide the necessary teachings for a continuous distillation system. This is not persuasive.
The Examiner respectfully disagrees with Applicant’s characterization of the Nelson and Roldan combination. Assuming arguendo, one of ordinary skill in the art would recognize that Nelson at least suggests a process for liquefaction of hydrogen. As shown in the Roldan remedies the deficiencies of Nelson by the additional heat exchange and cooling structures.
The current combination of prior art references teaches and suggests cooling the second stream in a second heat exchanger as a result of the modification in order to within a pressure or temperature range chosen by a user. Thus, applicant's arguments that the prior art does not suggest the claim language of to specifically match <103 K is considered unpersuasive.
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 IBRAHIM M ADENIJI whose telephone number is (571)272-5939. The examiner can normally be reached 8:00-5:00 PM.
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/IBRAHIM A. MICHAEL ADENIJI/Examiner, Art Unit 3763
/JOEL M ATTEY/ Primary Examiner, Art Unit 3763
1 The recitation of "in order to cool and optionally to liquefy the second mixture" recited in the claim has been considered a recitation of intended use. The prior art structure above is capable of performing as intended. It has been held that the recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus satisfying the claimed structural limitation. (MPEP 2114).
