Shiguang LI et al.

Patent Trials and Appeals Board

Oct 21, 2021

2020006742 (P.T.A.B. Oct. 21, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
14/870,906 09/30/2015 Shiguang LI GTI-2003 3843
42419 7590 10/21/2021
PAULEY ERICKSON & SWANSON
2800 WEST HIGGINS ROAD
SUITE 365
HOFFMAN ESTATES, IL 60169
EXAMINER
HOLECEK, CABRENA L
ART UNIT PAPER NUMBER
1776
MAIL DATE DELIVERY MODE
10/21/2021 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte SHIGUANG LI, SHAOJUN ZHOU, HOWARD S. MEYER, and
MIAO YU
Appeal 2020-006742
Application 14/870,906
Technology Center 1700
Before JAMES C. HOUSEL, CHRISTOPHER C. KENNEDY, and
SHELDON M. MCGEE, Administrative Patent Judges.
HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–6, 8–11, and 20–28. We have
jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies Gas Technology Institute and South
Carolina Research Foundation as the real parties in interest. Appeal Brief
(“Appeal Br.”) filed March 31, 2020, at 2.
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Application 14/870,906

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CLAIMED SUBJECT MATTER
The invention recited in the claims on appeal relates to an improved
method of producing high purity oxygen from air. Specification (“Spec.”)
filed September 30, 2015, at 1 (Field of the Invention).2
Claim 1, reproduced below from the Claims Appendix to the Appeal
Brief, is illustrative of the claimed subject matter:
1. A method of producing oxygen from an oxygen-containing
gas comprising the steps of:
feeding a gas to the first side of a first membrane, the gas
including nitrogen and oxygen;
feeding an oxygen-absorbing solvent selected from the
group consisting of poly(ethyleneimine)-cobalt, cobalt
porphyrins, cobalt porphyrin complexes, and combinations
thereof to a second side of the first membrane;
passing the oxygen through the first membrane, from the
first side to the second side of the first membrane, where the
oxygen is absorbed by the oxygen absorbing solvent to form
an oxygen-rich carrier solution;
feeding the oxygen-rich carrier solution to a first side of a
second membrane;
passing the oxygen from the oxygen-rich carrier solution
through the second membrane, from the first side of the
second membrane to a second side of the second membrane;
and
recovering gaseous oxygen in a purity of greater than
95% from the second side of the second membrane.

2 This Decision also cites to the Examiner’s Answer (“Ans.”) dated July 29,
2020, and the Reply Brief (“Reply Br.”) filed September 28, 2020.
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Independent claim 21 recites a method of producing oxygen from an
oxygen-containing gas similar to claim 1, wherein the first membrane is in
the form of one or more tubes defining a bore side (interior of the tubes) and
a shell side (exterior of the tubes), such that the gas is fed to the bore side
and the solvent is fed to the shell side.
Independent claim 26 recites a method of producing oxygen from an
oxygen-containing gas similar to claim 1, wherein the second membrane is
in the form of one or more tubes defining a bore side (interior of the tubes)
and a shell side (exterior of the tubes), such that the oxygen-rich carrier
solution is fed to the shell side and oxygen is recovered from the bore side.
REFERENCES
The Examiner relies on the following prior art:
Name Reference Date
Bonaventura US 4,602,987 July 29, 1986
Sirkar US 6,165,253 Dec. 26, 2000
REJECTIONS
The Examiner maintains, and Appellant requests our review of, the
following rejections:
1. Claim 21 under 35 U.S.C. § 112(b) as indefinite;
2. Claims 1–3 and 20 under 35 U.S.C. § 103 as unpatentable over
Bonaventura; and
3. Claims 1–6, 8–11, and 21–28 under 35 U.S.C. § 103 as
unpatentable over Sirkar in view of Bonaventura.
OPINION
We review the appealed rejections for error based upon the issues
Appellant identifies, and in light of the arguments and evidence produced
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thereon. Cf. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010)
(precedential) (cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed.
Cir. 2011) (“[I]t has long been the Board’s practice to require an applicant to
identify the alleged error in the examiner’s rejections.”)). After considering
Appellant’s arguments and the evidence of record, we are not persuaded of
reversible error in the Examiner’s rejections for substantially the fact
findings, reasoning, and conclusions set forth in the Examiner’s Answer,
which we adopt as our own. We offer the following for emphasis.
Rejection 1: Indefiniteness
The Examiner rejects claim 21 under 35 U.S.C. § 112(b) as indefinite
for reciting, on line 7, an adjective, “oxygen-absorbing,” without an
associated noun. Ans. 3. The Examiner also observes that claim 21, line 9,
recites “the oxygen-absorbing solvent” which lacks antecedent basis (due to
the missing noun on line 7.3 Id. at 4.
Appellant fails to address this rejection in the Appeal Brief (Ans. 17),
but acknowledges this issue in the Reply Brief (Reply Br. 3). In doing so,
Appellant also acknowledges that the Examiner’s review of claim 21 based
on the noun, “solvent,” being associated with the adjective, “oxygen-
absorbing,” is correct. Id.
Accordingly, we summarily affirm the Examiner’s indefiniteness
rejection of claim 21, but will decide the merits of the obviousness of this
claim on the same basis as the Examiner.

3 We observe that an indefiniteness rejection applied against an independent
claim often casts a similar indefiniteness cloud on claims dependent
therefrom, unless the dependent claims provide a corrective remedy to the
issue in the independent claim.
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Rejection 2: Obviousness over Bonaventura
The Examiner rejects claims 1–3 and 20 under 35 U.S.C. § 103 as
unpatentable over Bonaventura. Ans. 5–8. Appellant addresses claims 1, 2,
and 20 separately. Claim 3 will stand or fall with claim 2 from which it
depends.
Claim 1
The Examiner finds that Bonaventura discloses the method
substantially as recited in claim 1, except for the purity of the recovered
oxygen of greater than 95%. Ans. 5–7. However, the Examiner also finds
that Bonaventura teaches that some industries may require pure oxygen. Id.
at 21–22. Therefore, the Examiner determines that it would have been
obvious to an ordinary artisan to have optimized Bonaventura’s recovered
oxygen purity involving only routine skill in the art. Id. at 7 (citing In re
Aller, 220 F.2d 454, 456 (CCPA 1955) (“it is not inventive to discover the
optimum or workable ranges by routine experimentation”)).
Appellant argues that Bonaventura requires the added complexity and
expense of first electrochemically unloading oxygen from the carrier
complex and then passing the freed oxygen to the membrane for passage
through the membrane. Appeal Br. 7. As such, Appellant asserts that the
claimed invention requires feeding an “oxygen-rich carrier,” which “is the
oxygen absorbing solvent with the oxygen absorbed.” Id. Because
Bonaventura teaches “disassociat[ing] the oxygen from [the] complex by
electrodes upstream of the membrane,” Appellant contends that Bonaventura
fails to disclose or suggest feeding an oxygen-rich carrier solution to a first
side of a second membrane. Id. Appellant also contends that there is no basis
in the record, outside of Appellant’s disclosure, for modifying Bonaventura
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to feed oxygen complex directly to the second membrane without first
passing the oxidizing station. Id. at 8.
Appellant further argues that Bonaventura fails to show or suggest
recovering gaseous oxygen in a purity of greater than 95% from the second
side of the second membrane. Appeal Br. 8. In this regard, Appellant asserts
that Bonaventura discloses directly utilizing oxygen in a fuel cell without
release of the oxygen in gaseous form. Id.
Appellant’s arguments are not persuasive of reversible error. Contrary
to Appellant’s arguments that Bonaventura requires first electrochemically
unloading oxygen from the carrier complex and then passing the freed
oxygen to the membrane for passage through the membrane, Bonaventura
actually teaches that this step may be omitted. For example, Bonaventura
teaches that the “unloading of oxygen may be accomplished merely by
reducing the pressure of oxygen at the unloading station.” Bonaventura
7:60–63. Bonaventura also teaches that “[i]n an embodiment of the invention
that is particularly useful for purifying oxygen from air, the electrochemical
cell can be eliminated.” Id. at 35:47–49; see also id. at 22:26–33 (discussing
that oxygen can be released “without requiring oxidation or reduction by an
electrochemical cell”). Bonaventura teaches that such an embodiment
(lacking an electrochemical cell) “takes advantage of the reversible nature of
the oxygen binding reaction itself.” Id. at 35:52–53. According to
Bonaventura, the recovery of gaseous oxygen can be accomplished by
connecting an inlet port of a compressor to the second side of the second
membrane, thereby producing compressed, purified oxygen. Id. at 35:58–68.
In addition, Bonaventura compares the disclosed process and system to a
typical oxygen production facility producing 95% oxygen, which
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Bonaventura characterizes as a lower purity product than the disclosed
invention. Id. at 35:31–46. Thus, even if claim 1 excludes electrochemically
unloading oxygen from the carrier complex, Bonaventura teaches an
embodiment without this electrochemical unloading step and suggests
recovery of gaseous oxygen in a purity greater than 95%.
Notwithstanding Bonaventura’s alternative embodiment, we note that
claim 1 recites the method steps using the transitional term, “comprising.”
“The word ‘comprising’ transitioning from the preamble to the body signals
that the entire claim is presumptively open-ended.” Gillette Co. v. Energizer
Holdings, Inc., 405 F.3d 1367, 1371–1372 (Fed. Cir. 2005). “‘Comprising’
is a term of art used in claim language which means that the named elements
are essential, but other elements may be added and still form a construct
within the scope of the claim.” Genentech, Inc. v. Chiron Corp., 112 F.3d
495, 501 (Fed. Cir. 1997). Thus, Bonaventura’s embodiment utilizing
electrochemical unloading steps is not excluded from claim 1, at least by
virtue of the transitional term.
We further note that claim 1 recites that a gas including oxygen is fed
to the first side of a first membrane and an oxygen-absorbing solvent is fed
to the second side of the first membrane, and oxygen passes through the
membrane and is absorbed by the solvent “to form an oxygen-rich carrier
solution.” There is no dispute that Bonaventura teaches both of these steps.
Claim 1 further recites that the oxygen-rich carrier solution is fed to a first
side of a second membrane. Here, Appellant contends that Bonaventura fails
to feed the oxygen-rich carrier solution to the first side of a second
membrane because Bonaventura’s oxygen-rich carrier solution is fed to an
electrochemical cell to release oxygen from the carrier. However, though
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oxygen is released from the carrier in this embodiment, Bonaventura teaches
that the freed oxygen and carrier solution are fed to the first side of the
second membrane. Bonaventura 20:16–51. Claim 1 does not require that the
oxygen-rich carrier solution is fed directly to the second membrane, nor that
the oxygen remain absorbed onto the carrier at the time the solution is fed to
the second membrane. Because Bonaventura’s solution includes both the
oxygen absorbed onto the carrier from the first membrane and the carrier,
this solution is still the oxygen-rich carrier solution. Thus, even
Bonaventura’s electrochemical embodiment feeds the oxygen-rich carrier
solution to the second membrane as claim 1 requires.
Further, although Bonaventura discloses that this embodiment may be
combined with a fuel cell to directly deliver oxygen to the fuel cell without
release of gaseous oxygen (id. at 20:52–67), this disclosure is merely one
possible use of this embodiment. Bonaventura also discloses this
embodiment may be used to produce gaseous oxygen. Id. at 20:16–18. In
addition, Appellant fails to rebut or otherwise address the Examiner’s
position that optimizing Bonaventura’s recovered oxygen purity involves
only routine skill in the art and, therefore, would have been obvious to one
of ordinary skill in the art.4

4 We note the dispute between the Examiner and Appellant regarding
whether some oxygen would remain bound to Bonaventura’s carrier when
fed to the second membrane after passing through the electrochemical
oxygen unloading station. Compare Ans. 18 and 20 with Reply Br. 2–3.
However, because we agree with the Examiner that Bonaventura feeds
oxygen-rich carrier solution to the second membrane in both the direct
embodiment and in the indirect embodiment as discussed above, resolution
of this dispute is unnecessary to our Decision.
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Claim 2
With regard to claim 2, the Examiner finds that Bonaventura teaches
that the gas is fed to the first side of the first membrane under atmospheric
pressure, which the Examiner interprets as “using pressure.” Ans. 7.
However, Appellant argues that feeding a gas to a membrane using pressure,
as claim 2 requires, is different from simply having a membrane in contact
with a gas under atmospheric pressure. Appeal Br. 8. This argument is not
persuasive because Appellant fails to explain in any detail why the claim 2
limitation is distinguished from a gas under atmospheric pressure. Indeed,
Bonaventura recognizes that the transport of oxygen across the membranes
depends in part on the partial pressure of oxygen on opposing sides of the
membranes. Bonaventura 8:20–34, 15:31–40, 17:34–42 and 53–61, 22:26–
33. As the Examiner finds, atmospheric pressure is 14.7 psi (typically
absolute and at sea level), such that gas is fed to the first side of the
membrane under pressure. Ans. 22. Accordingly, we sustain the Examiner’s
obviousness rejection of claim 2.
Claim 20
With regard to claim 20, the Examiner finds that although
Bonaventura fails to expressly teach producing gaseous oxygen in a purity of
greater than 99%, Bonaventura nonetheless suggests producing pure oxygen
(purity greater than 99%). Ans. 22–23. Appellant merely recites the
limitation of claim 20 and asserts that Bonaventura fails to disclose or
suggest this limitation. Skeletal arguments or arguments merely amounting
to assertions that the references do not disclose or suggest certain claim
limitations are not arguments for separate patentability within the meaning
of 37 C.F.R. § 41.37(c)(1)(iv). See In re Lovin, 652 F.3d 1349, 1356–57
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(Fed. Cir. 2011). Accordingly, we sustain the Examiner’s obviousness
rejection of claim 20.
Rejection 3: Obviousness over Sikar and Bonaventura
The Examiner rejects claims 1–6, 8–11, and 21–28 under 35 U.S.C.
§ 103 as unpatentable over Sirkar in view of Bonaventura. Ans. 8–17.
Appellant does not argue the claims under this rejection separately. We
select claim 1 as representative; claims 2–6, 8–11, and 21–28 stand or fall
with claim 1. 37 C.F.R. § 41.37(c)(1)(iv) (2019).
The Examiner finds that Sirkar discloses the method substantially as
recited in claim 1, except for recovery of gaseous oxygen at a purity of
greater than 95% and the use of an oxygen absorbing solvent selected from
the group consisting of poly(ethyleneimine)-cobalt, cobalt porphyrins, cobalt
porphyrin complexes, and combinations thereof. Ans. 8–9. However, the
Examiner finds that Bonaventura teaches that such compounds were known
in the art as oxygen-absorbing carriers for reversible binding of oxygen. Id.
at 9. In addition, the Examiner finds that Bonaventura teaches recovery of
gaseous oxygen at a purity of at least 95%. Id. The Examiner concludes that
it would have been obvious to include Bonaventura’s oxygen-absorbing
carriers in Sirkar’s method in order to bind oxygen reversibly and that it
would have been obvious to optimize the oxygen purity. Id. at 9–10.
Appellant argues that Sirkar fails to teach that the starting gas
includes nitrogen and oxygen when oxygen is the target gas to be collected.
Appeal Br. 9. Appellant concedes that Sirkar teaches that the starting gas
may be air, nitrogen, or oxygen, but asserts that Sirkar removes target
volatile compounds from these starting gases, rather than oxygen. Id. at 10.
Appellant contends that Sirkar discloses gas scrubbing and regeneration of
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absorbents, rather than separation of oxygen from air. Id. In addition,
Appellant asserts that the Sirkar and the Bonaventura processes are
essentially opposite, and contends that there is no basis for their combination
absent Appellant’s disclosure. Id. at 10, 11. And Appellant argues that any
combination of these references would still incorporate Bonaventura’s
electrode-based oxidation/reduction. Id. at 11.
Appellant’s arguments are not persuasive of reversible error. To
begin, as explained above, not only does Bonaventura expressly teach that
electrode-based oxidation/reduction is optional and may be omitted, but
claim 1 does not exclude electrode-based oxidation/reduction steps from the
method. Moreover, Appellant fails to explain in any detail how and why
Sirkar’s and Bonaventura’s processes are essentially opposites. Sirkar
discloses a system for transferring a solute or target from a feed gas to an
absorbent liquid separated by a membrane. Sirkar 3:58–62. Although Sirkar
is also concerned with removal of volatile organic compounds from the feed
gas such as air or nitrogen, Sirkar discloses that the gas species to be
selectively removed may be oxygen. Id. at 17:52–53. Thus, Sirkar’s process
is similar to Bonaventura’s which selectively removes oxygen from a feed
gas such as air by transferring oxygen from the feed gas to an absorbent
liquid separated by a membrane. The fact that Sirkar’s membranes are in the
form of hollow fibers whereas Bonaventura’s are shown to be flat
membranes alone does not demonstrate that their respective processes are
opposite, especially since both membrane forms perform the same selective
separation and transfer.
Further, we disagree with Appellant’s characterization of Sirkar as
directed to gas scrubbing and regeneration. Sirkar merely indicates that the
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inventive absorbent scheme and operational conditions are equally
applicable to gas scrubbing and regeneration. This teaching does not negate
the fact that Sirkar’s process is a selective removal process using membrane
separation and an absorbent liquid as recited in claim 1. Further, the teaching
that the gas species to be selectively removed may be oxygen is similarly not
limited to gas scrubbing and regeneration, but to both the inventive process,
as well as gas scrubbing and regeneration. Therefore, a preponderance of the
evidence supports the Examiner’s findings, reasoning, and conclusion that
the claim 1 method would have been obvious over the combination of Sirkar
and Bonaventura.
Accordingly, we sustain the Examiner’s obviousness rejection of
claim 1, and claims 2–6, 8–11, and 21–28.
CONCLUSION
Upon consideration of the record and for the reasons set forth above
and in the Examiner’s Answer, the Examiner’s decision to reject claims 1–6,
8–11, and 21–28 under 35 U.S.C. § 103 is affirmed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
21 112 Indefiniteness 21
1–3, 20 103 Bonaventura 1–3, 20
1–6, 8–11,
21–28
103 Bonaventura, Sirkar 1–6, 8–11,
21–28

Overall
Outcome
1–6, 8–11,
20–28

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TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED