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 .
This action is a response to the amendments and remarks filed on 4 November 2025.
Response to Amendment
Claims 1, 11, and 16 have been amended. Claims 2, 5, 14-15, and 19-20 have been canceled. Claims 1, 3-4, 6-13, and 16-18 are pending. Claims 4, 6-10, 13, and 18 remain withdrawn from consideration. Claims 1, 3, 11-12, and 16-17 are examined herein. In the previous action (Non-Final Rejection filed on 9 September 2025), claims 2-3, 5, 11, 14-17, and 19-20 were indicated as containing allowable subject matter. Allowable subject matter of claim 2 has been incorporated into claim 1 by amendment.
Response to Arguments
Applicant argues that the amendments to the claims render the rejections under the rejections under 35 USC 112(b) moot (Remarks, p. 6, middle).
In response, while the rejections of the canceled claims are indeed moot, the amendments introduce other sources of indefiniteness, as discussed below.
Upon further consideration and search, a new ground(s) of rejection, necessitated by amendment, is presented herein based upon Doshi (US 4,690,695). Said new grounds of rejection are presented herein as a final rejection, based upon amendment. See MPEP 706.07(a).
Claim Objections
Claim 11 is objected to because of the following informality:
Claim 11: The claim lacks a closing period.
Appropriate correction is required.
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, 3, 11-12, and 16-17 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.
Claim 1: The claim recites, “a high purity gas stream” (line 6) and “a gas stream lean in high purity gas stream” (line 9). These limitations together are indefinite for the following reasons: (1) It is unclear if “high purity” is to be understood as Applicant’s preferred name for a stream from a PSA device or if the relative term “high purity” is meant to claim a certain purity level, such as 95% (p. 6, line 25); (2) “Lean in high purity gas stream” lack an article (e.g., lean in the high purity gas stream), so it is unclear if the antecedent in line 6 is being referenced; (3) It is unclear what is meant by “a gas stream lean in high purity gas stream” because it is unclear how one stream can include another stream, and it is unclear how one stream can be interpreted as “lean” in another, entirely separate gas stream, as “lean” implies some presence (defined by Merriam-Webster as “deficient in an essential or important quality or ingredient”); (4) It is unclear how a stream produced from a PSA device can be present in a stream produced from a membrane device, particularly when the PSA device stream is not the stream introduced into the membrane device; and (5) it is unclear how a stream can be “lean” in a species that is also ”high purity” in the same stream, raising doubt about what is meant by “high purity.” It is noted that a “product gas” might be normally construed in the art to suggest a stream comprising a species in sufficient concentration to be valuable as a “product,” but the preamble makes clear that “product gas” is meant to designate a target species for the purification. However, it appears that “high purity gas stream” cannot be interpreted similarly.
Claim 3 is rejected because of its dependence from claim 1.
Claim 11: The claim is indefinite for the same reasons given above in regard to claim 1, i.e., it is unclear how the terms “a high purity product gas stream” (line 7) and “a gas stream lean in high purity gas stream” (line 9) limit the claim.
In addition, claim 11 is indefinite because it is not internally consistent. For example, in the sixth bullet point step, “thereby producing the gas stream lean in high purity gas stream and the permeate stream” refers to the streams produced the third bullet point step. However, the feed into the membrane separation device in the sixth step includes a second PSA off-gas stream, whereas the feed into the membrane separation device of the third step is an off-gas stream of a different (implicitly, a ”first”) PSA device, so the streams in the third and sixth steps cannot be the same. Likewise, the feed into the membrane separation device of the sixth step includes components from the products of the membrane separation device in the third step, i.e., the permeate of step 3 passes into the second PSA device, and a stream from the second PSA device is fed into the membrane separation device of the third step, so step six imagines that the products of a membrane separation result from a separation of a feed that itself includes a product of the membrane separation, which confuses cause and effect, as it is incoherent to recite that the feed to the sixth step membrane includes part of one of the products of the same separation. It is noted that the figures do not provide clarification because the membrane 104 permeate 106 is never fed to the second PSA 117 in any figure, as step 4 requires. Instead, it is fed to the first PSA 109.
Claim 12 is rejected because of their dependence from claim 11.
Claim 16: The claim is indefinite for the same reasons given above in regard to claim 1, i.e., it is unclear how the terms “a high purity product gas stream” (line 7) and “a gas stream lean in high purity gas stream” (line 9) limit the claim.
In addition, as in claim 11, the claim is internally inconsistent. For example, in the sixth bullet point step, “thereby producing the gas stream lean in high purity gas stream and the permeate stream” refers to the streams produced the third bullet point step. However, the feed into the membrane separation device in the sixth step includes a second PSA off-gas stream, whereas the feed into the membrane separation device of the third step is an off-gas stream of a different (implicitly, a “first”) PSA device, so the streams in the third and sixth steps cannot be the same. Likewise, the feed into the membrane separation device of the sixth step includes components from the products of the membrane separation device in the third step, i.e., the permeate of step 3 passes into the second PSA device, and a stream from the second PSA device is fed into the membrane separation device of the third step, so step six imagines that the products of a membrane separation result from a separation of a feed that itself includes a product of the membrane separation, which confuses cause and effect, as it is incoherent to recite that the feed to the sixth step membrane includes part of one of the products of the same separation. As another example, in step 8, the claim recites, “dividing the combined feed stream into a first portion and a second portion,” but this cannot be done in sequence because the combined feed stream has already been introduced to the PSA device (step 2), and so the following steps cannot be understood in the context of the previous steps. Furthermore, the last step imagines that its feed (“combining . . . and introducing”) and product streams (“the high purity gas stream and the off-gas stream”) are the same as those of the second step, but the feed to the third PSA (step 9) uses a part (the “second portion”) of the feed stream (“the combined feed stream”) claimed to be sent to the “first” PSA (steps 1 and 2), so the steps disagree about the fate of the “combined feed stream.” Fig. 3 does not offer clarification for the last step because no stream from the third PSA 303 is sent to the first PSA 109.
Claim 17 is rejected because of its dependence from claim 16.
Claim Rejections - 35 USC § 102
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.
Claims 1 and 3 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Doshi (US 4,690,695).
Regarding claim 1, Doshi discloses a process (claim 1) for obtaining a high purity product gas (col. 8, lines 41-43) from a gas mixture (col. 10, line 68) (i.e., a method of purifying a gas composed of a product gas and one impurity gas) comprising:
combining a first stage permeate 26 with a second stage permeate 35 to form a permeate stream in line 28 (Fig. 2; col. 8, lines 37-40, 62-65) (i.e., combining a feed stream with a second stream thereby forming a combined feed stream),
passing line 28 to a PSA system 29 (coil. 8, lines 40, 66-67) (i.e., introducing the combined feed stream into a pressure swing adsorption device) to produce a high purity product 30 of a first component and a PSA waste stream 31 for recycling (col. 8, lines 41-45, 51; claim 6) (i.e., thereby producing a high purity product gas stream and an off-gas stream), and
compressing recycle stream 31 and passing the recycle gas through line 33 to a second stage membrane system 34 (col. 8, lines 54-56) (i.e., introducing the off-gas stream into a membrane separation device) to form a second stage non-permeate gas 36 enriched in a second component and the second stage permeate 35 for recycling (col. 8, line 64; col. 9, lines 1-3) (i.e., thereby producing a gas stream lean in product gas high purity gas stream and a permeate stream, wherein the second stream is the permeate stream).
Regarding claim 3, Doshi teaches that the high purity product is helium (col. 10, lines 42, 68) (i.e., wherein the product gas is helium).
Allowable Subject Matter
The following is a statement of reasons for the indication of allowable subject matter:
A thorough search for pertinent prior art did not locate any prior art that discloses or suggests the invention recited in claims 11-12 and 16-17.
The concept of a method of purifying a gas composed of a product gas and one or more impurity gases comprising the steps of claims 11 or 16 is considered to define patentable subject matter over the prior art.
The closest prior art is Doshi (US 4,690,695), which discloses a process (claim 1) for obtaining a high purity product gas (col. 8, lines 41-43) from a gas mixture (col. 10, line 68) comprising:
combining a first stage permeate 26 with a second stage permeate 35 to form a permeate stream in line 28 (Fig. 2; col. 8, lines 37-40, 62-65),
passing line 28 to a PSA system 29 (coil. 8, lines 40, 66-67) (i.e., introducing the combined feed stream into a pressure swing adsorption device) to produce a high purity product 30 of a first component and a PSA waste stream 31 for recycling (col. 8, lines 41-45, 51; claim 6), and
compressing recycle stream 31 and passing the recycle gas through line 33 to a second stage membrane system 34 (col. 8, lines 54-56) (i.e., introducing the off-gas stream into a membrane separation device) to form a second stage non-permeate gas 36 enriched in a second component and the second stage permeate 35 for recycling (col. 8, line 64; col. 9, lines 1-3).
However, Doshi does not suggest the steps 4-7 of claim 11, or steps 4-10 of claim 16.
Claims 11-12 and 16-17 would be allowable if rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action.
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 GABRIEL E GITMAN whose telephone number is (571)272-7934. The examiner can normally be reached M-Th 7:15-5:45pm.
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/GABRIEL E GITMAN/Primary Examiner, Art Unit 1772
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