Ex Parte Bull et al

Patent Trial and Appeal Board

Mar 25, 2019

12612142 (P.T.A.B. Mar. 25, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/612,142 11/04/2009
109171 7590 03/27/2019
WOMBLE BOND DICKINSON (US) LLP
Attn: IP Docketing
P.O. Box 7037
Atlanta, GA 30357-7037
FIRST NAMED INVENTOR
Ivor Bull
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
B248 2260US.l (0108.4) 3835
EXAMINER
DA VIS, SHENG HAN
ART UNIT PAPER NUMBER
1732
NOTIFICATION DATE DELIVERY MODE
03/27/2019 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
IPDocketing@wbd-us.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte IVOR BULL, AHMAD MOINI, and MUKTA RAI
Appeal2018-002220
Application 12/612, 142
Technology Center 1700
Before BRADLEY R. GARRIS, KAREN M. HASTINGS, and
MICHAEL P. COLAIANNI, Administrative Patent Judges.
COLAIANNI, Administrative Patent Judge.
DECISION ON APPEAL
Appeal2018-002220
Application 12/612, 142
Appellants 1 appeal under 35 U.S.C. § 134 the final rejection of claims
1, 4, 5, 8-13, 15-23, 28, and 29. We have jurisdiction over the appeal
pursuant to 35 U.S.C. § 6(b ).
We AFFIRM.
Appellants' invention is directed to a selective catalytic article that
includes zeolites that have a chabazite (CHA) crystal structure. (Claim 1;
Spec. ,r 3).
Claim 1 is illustrative:
1. A selective catalytic reduction catalytic article
comprising a natural or synthetic aluminosilicate zeolite, the
zeolite having exchange sites and a CHA crystal structure and
the zeolite promoted at the exchange sites with one or more
metal cations selected from iron, copper and combinations
thereof, the zeolite being disposed on a substrate, the article
effective to reduce NOx in exhaust streams from diesel and
gasoline engines, wherein the zeolite has a mole ratio of silica
to alumina of less than 15 and has an alkali content of less than
about 0.5 weight percent, and wherein the catalytic article
exhibits the selective catalytic reduction ofNOx with ammonia
exceeding at least about 50% in exhaust gas streams at 250° C.
Appellants appeal the following rejections:
1. Claims 1, 4, 5, 8, and 29 are rejected under 35 U.S.C. § 103 as
unpatentable over Maeshima (US 4,046,888, issued Sept. 6, 1977) in
view of Maher (US 3,402,996, issued Sept. 24, 1968), Famos (US
5,589,147, issued Dec. 31, 1996), and Ward (US 3,945,943, issued
Mar. 23, 1976).
1 The Appeal Brief on page 1 indicates that "BASF Corporation" is the
assignee of record.
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Application 12/612, 142
2. Claim 9 is rejected under 35 U.S.C. § 103 as unpatentable over
Maeshima in view of Maher, Famos, Ward, and further in view of
Hubig (US 2007/0081934 Al, published Apr. 12, 2007).
3. Claim 10 is rejected under 35 U.S.C. § 103 as unpatentable over
Maeshima in view Maher, Famos, Ward and in further view of Li
'095 (US 2009/0048095 Al, published Feb. 19, 2009) and Li '362
(US 2010/0092362 Al, published Apr. 15, 2010).
4. Claims 11, 12, 13, 17, 18, 19, and 23 are rejected under 35 U.S.C.
§ I03(a) as unpatentable over Maeshima in view of Maher, Famos,
Ward, and Beutel (US 2008/0045405 Al, published Feb. 21, 2008).
5. Claims 15, 16, 28, and 29 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Maeshima in view of Maher, Famos, Ward, and in
further view ofHubig, and Gaffney (EP 0391351 A2, published Oct.
10, 1990).
6. Claims 20 and 22 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Maeshima in view of Maher, Famos, Ward, Beutel,
and further in view of Wei (US 2009/0031710 Al, published Feb. 5,
2009).
7. Claim 21 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Maeshima in view of Maher, Famos, Ward, Beutel, Wei, and Long
(R.Q. Long et al., "Selective Catalytic Oxidation (SCO) of Ammonia
to Nitrogen over Fe-Exchanged Zeolites" J. of Catalysis 201, 145-152
(2001)). [
Appellants' arguments focus on the subject matter of claim 1 only (App. Br.
3-17). Any claim not argued separately will stand or fall with our analysis
of the rejection of claim 1.
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Application 12/612, 142
FINDINGS OF FACT & ANALYSIS
The Examiner's findings and conclusions with respect to claim 1 are
located on pages 7 to 9 of the Final Action. The Examiner finds that
Maeshima discloses a selective catalyst reduction (SCR) catalyst made of
aluminosilicate obtained by exchanging an alkali metal ion with a metal for
the reduction ofNOx (Final Act. 7). The Examiner finds that Maeshima
discloses that the metal can be iron or copper and the silica to alumina ratio
(SAR) is 2 or more (Final Act. 7). The Examiner finds that Maeshima
teaches that the zeolite can have a chabazite crystal structure (Final Act. 7).
The Examiner finds that Maeshima does not teach the following: 1) the
alkali content is less than 0.5 wt. %, 2) the zeolite is disposed on a substrate,
3) the zeolite is used in a gasoline or diesel engine, and 4) the NOx reduction
when ammonia is used is at least 50% in the exhaust gas stream at 250°C
(Final Act. 7). The Examiner finds that Maher discloses reducing sodium
ion concentrations in an ion exchange zeolite using ammonium exchange
(Final Act. 7). The Examiner finds that the level of sodium in the zeolite can
be reduced to below 0.5% (Final Act. 7). The Examiner finds that Ward
teaches improving zeolite aluminosilicate catalysts that may be used in a
denitrification reaction by lowering the alkali metal levels to as low as 0.5%
to enhance thermal stability and tolerance to high temperatures (Final Act.
7-8). The Examiner concludes that it would have been obvious to reduce
the sodium levels to below 0.5 wt.% as taught by Maher by performing
additional exchange steps because Ward teaches that reduced sodium levels
improve hydrothermal stability and tolerance to high temperatures (Final
Act. 8).
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Application 12/612, 142
The Examiner finds that Famos discloses a SCR catalyst usable in an
engine that is coated on a substrate and can be a natural zeolite (Final Act.
8). The Examiner further finds that the engine in Famos would have been
either gasoline or diesel as they are standard in the art (Final Act. 8). The
Examiner concludes that it would have been obvious to coat the catalyst on a
substrate for use in a gasoline or diesel engine, as taught by Famos, for use
with Maeshima, Maher and Ward because it is known to coat SCR catalysts
on a substrate for use with engines to reduce NOx in these exhaust gas
streams (Final Act. 8-9). The Examiner finds that because the catalysts are
the same it is reasonable to expect that each catalyst has the same NOx
reducing property (Final Act. 9).
Appellants argue that they surprisingly discovered that chabazite
(CHA) zeolite materials exhibit strong ammonia SCR activity even after
hydrothermal aging (App. Br. 6). Appellants contend that the declaration of
one of the present inventors, Ahmad Moini (hereinafter "Moini
Declaration"), is evidence that one of ordinary skill in the art would not have
used a chabazite catalyst with a SAR ( silica to alumina ratio) below 15
(App. Br. 6). Appellants argue that as explained in the Moini Declaration,
the patent to Bull (US 7,601,662) and the pre-grant publication to Li '060
(US 2008/0241060) each demonstrate that one of ordinary skill in the art
would not have used a chabazite zeolite with a SAR less than 15 (App. Br.
6). Appellants contend that Bull and Li '060 teach away from using
chabazite zeolites having a SAR below 15 due to the instability of the lower
SAR catalysts at high temperatures ( e.g., 700°C) found in exhaust gases
(App. Br. 6). Appellants contend that Bull and Li '060 teach away from
chabazite catalysts with SAR values below 15 in ammonia applications and
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Application 12/612, 142
instead teach to use chabazite catalysts with a preferred SAR range from 25
to 40 (App. Br. 6, 7). Appellants contend that Li teaches that the "low-silica
chabazite" with a SAR of 6.3 as shown in Table 1 was largely destroyed
after aging at 700°C due to the precipitous drop in surface area of the
catalyst (App. Br. 7).
Regarding Maeshima, Appellants argue that Maeshima contains a
broad disclosure for aluminosilicates having a SAR of 2 or greater but
Maeshima does not teach specifically that chabazites should have a SAR
value of 2 or greater (App. Br. 8-9). Appellants argue that Maeshima's
disclosure is directed to faujasite/zeolite frameworks with a SAR below 15,
not to chabazite zeolites (App. Br. 9). Appellants contend that Famos
teaches that exhaust gas temperatures can be as high as 1000°C and
Maeshima's upper temperature limit for the zeolite catalysts is half the
temperature disclosed by Famos (i.e., 500°C) (App. Br. 10). Appellants
argue that one of ordinary skill in the art would have been aware of the
problems associated with using chabazite zeolites with low SAR values at
high temperatures and would not have used Maeshima's chabazite zeolite in
an exhaust gas system as taught by Famos (App. Br. 10).
These arguments are not persuasive of reversible error.
Although claim 1 recites the intended use for the catalyst article in
exhaust streams from diesel and gasoline engines, claim 1 does not recite
any particular temperature of the exhaust gases. Appellants contend that
Famos teaches that exhaust gases may have a temperature as high as
1000°C, but Famos also teaches that the exhaust gases may be as low as
200°C, which overlaps with the temperature range disclosed by Maeshima
(Famos col. 4, 11. 40-42; Maeshima col. 3, 11. 23-25). Maeshima discloses
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treating exhaust gas maintained at a temperature of 200 to 500°C with
ammonia and a zeolite to reduce NOx (Maeshima col. 2, 11. 47-50).
Maeshima further discloses that the exhaust gas temperature is adjusted to a
temperature of 200 to 500°C and discloses using an economizer ( e.g., a heat
exchanger) to achieve the desired exhaust gas temperature (Maeshima, col.
2, 11. 48-53; col. 7, 11. 20-23). Maeshima provides means to maintain and
achieve the desired exhaust gas temperature. Claim 1 uses the open-ended
transitional claim language comprising and so does not exclude using
Maeshima's economizer to maintain the desired exhaust gas temperature.
Maeshima' s teaching to maintain the exhaust temperature between
200 and 500°C undercuts Appellants' argument that Bull and Li teach away
from using chabazite zeolites in high temperature exhaust gas. Bull teaches
that at temperatures higher than 500°C the activity of metal-promoted
zeolites begins to decline (col. 1, 11. 35-38). Appellants allege that Li '060
shows that Comparative Example 1 that uses low-SAR chabazite zeolites
having a SAR of 6.3 is destroyed after hydrothermal aging at 700°C because
the surface area drops precipitously (App. Br. 6). The nature of Bull and Li
'060's disclosures do not teach away from using chabazite zeolites with a
low-SAR in Maeshima. In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994)
("Although a reference that teaches away is a significant factor to be
considered in determining unobviousness, the nature of the teaching is
highly relevant, and must be weighed in substance."). Rather, teachings in
Maeshima, Bull and Li '060 would have suggested cooling the exhaust gas
to within a temperature range of 200 to 500°C before treating with zeolite
that may include chabazite zeolites encompassed by the claim. As noted
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Application 12/612, 142
above, claim 1 does not exclude using a heat exchanger to control the
exhaust gas temperature.
Maeshima may include a broad disclosure of suitable zeolites having a
SAR of 2 or more. Nevertheless, Maeshima discloses zeolites having a
chabazite crystal structure and a SAR of 2 to 6. Maeshima's disclosure is
not limited to the preferred embodiments that use the faujasite zeolites. All
of Maeshima's disclosures, including the non-preferred embodiments, must
be considered. In re Lamberti, 545 F.2d 747, 750 (CCPA 1976).
Appellants argue that Maher, Gaffney and Hubig are non-analogous
art (App. Br. 11-12). Appellants contend that the field of Appellants'
endeavor is selective catalytic reduction (SCR) catalytic articles and exhaust
gas treatment systems and methods using such catalytic articles to reduce
NOx in a gas stream (App. Br. 11-12). Appellants argue that Gaffney is
directed to zeolites used in a completely different field of use (i.e., removal
of trace gases from argon) (App. Br. 12). Appellants contend that Ward's
denitrogenation disclosure would not be understood by one of ordinary skill
in the art to refer to SCR reactions for use in treating exhaust gas streams but
rather another form of hydrocarbon conversion (App. Br. 12). Appellants
argue that Ward is directed to hydrogenative hydrocarbon conversion, which
is not a SCR reaction to reduce NOx species in an exhaust gas (App. Br. 13).
Appellants contend that Maher is directed to the same general field as Ward,
hydrocarbon conversion, which is non-analogous to the field of endeavor of
the claimed invention (App. Br. 13).
Appellants contend that neither Ward, Maher, nor Gaffney is
reasonably pertinent to Appellants' problem (App. Br. 14). Appellants argue
that the problem solved by their invention is enabling use of a low SAR
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Application 12/612, 142
chabazite material to reduce efficiently NOx in a gaseous exhaust stream via
a SCR reaction under hydrothermal conditions (App. Br. 14). Appellants
contend that Gaffney is not directed to NOx reduction reactions of any kind
(App. Br. 14). Appellants argue that Ward and Maher are directed to
hydrocarbon conversion processes not NOx reduction of an exhaust gas
stream using SCR reaction (App. Br. 14).
Prior art is considered analogous if it is either ( 1) from the same field
of endeavor, regardless of problem addressed, or (2) if not from the same
field of endeavor the reference still is reasonably pertinent to the particular
problem with which the inventor was involved. In re Clay, 966 F.2d 656,
659 (Fed. Cir. 1992). The Supreme Court directs us to construe the scope of
analogous art broadly, stating "familiar items may have obvious uses beyond
their primary purposes, and a person of ordinary skill often will be able to fit
the teachings of multiple patents together like pieces of a puzzle." Wyers v.
Master Lock Co., 616 F.3d 1231, 1238 (Fed. Cir. 2010) citing KSR Int'! Co.
v. Teleflex, Inc., 550 U.S. 398, 402 (2007).
The Specification describes the "technical field" as chabazite zeolite
catalysts, methods for their preparation, and their use in exhaust gas
treatment systems (Spec. ,r 3). Claim 1 is directed to a selective catalytic
reduction catalytic article comprising a natural or synthetic aluminosilicate
zeolite, the zeolite having exchange sites and a chabazite crystal structure
having a ratio of silica to alumina (SAR) less than 15 and an alkali content
of less than about 0.5 weight percent with the intended use of the catalytic
article to reduce NOx in exhaust systems of diesel and gasoline engines.
Claim 1 further recites a property of the catalytic article where the article
exhibits the selective catalytic reduction ofNOx with ammonia exceeding at
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Application 12/612, 142
least about 50% in exhaust gas streams at 250°C. Based on claim 1 and the
Specification, the field of endeavor is broadly directed to chabazite zeolite
catalysts that may be used to treat exhaust gas. A chabazite zeolite catalyst
possessing the same structure and composition as recited in claim 1 would
reasonably be expected to have the recited property. In other words, the
field of endeavor includes zeolites generally including the chabazite crystal
structure with a SAR less than 15 and alkali content of less than 0.5% and
their use in exhaust systems with the attendant property being a
characteristic of the zeolite.
Based on these findings regarding the field of endeavor, we find that
Maher, Gaffney, and Ward are in the same field of endeavor. All three
references are concerned with zeolite catalysts and their use in catalyzing
nitrogen removal. Gaffney is directed to chabazite zeolites and improving
adsorption of nitrogen in the zeolite (Gaffney 2:4--6). Although Appellants
argue that one of ordinary skill in the art would not find Gaffney useful in
selecting zeolite material for SCR processes (Reply Br. 5) that argument is
premised on the erroneous argument that the field of endeavor is limited
solely to ammonia-SCR processes.
Ward is directed to crystalline aluminosilicate zeolite catalysts that
may be used in denitrogenation reactions ( col. 6, 1. 45). Appellants contend
that Ward's denitrogenation is directed to a hydrocarbon conversion
reaction, not SCR using ammonia (Reply Br. 5). Appellants' argument is
not persuasive because Ward's denitrogenation would still include removing
nitrogen from the hydrocarbon. Moreover, Ward teaches that the
aluminosilicate zeolites have better thermal stability in basic environments
including "ammoniacal solutions" or ammonia atmospheres (Ward, col. 6, 11.
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10-20). Additionally, Ward is also reasonably pertinent to Appellants'
problem of improving thermal stability of aluminosilicate zeolites, including
chabazite zeolites, by, inter alia, reducing the alkali content of the zeolite.
Maher is directed to improving the thermal stability of aluminosilicate
zeolites which would appear to be in a similar field of endeavor as
Appellants' chabazite zeolite. Nevertheless, Maher appears to be reasonably
pertinent to Appellants' problem of improving the thermal stability of
aluminosilicate zeolites. Maher teaches improving the thermal stability in
aluminosilicate zeolites by reducing the sodium ion concentration ( col. 1, 11.
45-50).
Appellants question the Examiner's reliance on Ward for teaching that
reducing sodium levels improve thermal stability of the zeolite (App. Br.
14). The Examiner provides multiple citations to Ward where it is taught to
reduce alkali metal levels and that so doing produces a zeolite with
improved thermal stability (Final Act. 7-8). Appellants do not specifically
show error with the Examiner's finding regarding Ward's teaching to reduce
alkali metal content of the zeolite. Maher teaches reducing sodium in
zeolites improves thermal stability (col. 1, 11. 45-50). In other words, the
combined teachings of the references would have suggested reducing the
sodium content of a zeolite to improve thermal stability of the zeolite.
Appellants contend that the Moini Declaration explains that the
evidence in the Specification establishes that it was surprising and
unexpected that by reducing the sodium content of the chabazite zeolite with
a silica to alumina ratio (SAR) of less than 15 would have good
hydrothermal stability for use in treating exhaust gas (App. Br. 15).
Appellants contend that as shown in Li '060 the low-silica chabazite zeolite
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with a SAR of 6.3 is completely destroyed after aging at 700°C (App. Br.
16).
Although Appellants allege that evidence in the Specification
establishes unexpected results, no evidence in the Specification has been
cited or explained by Appellants. The Moini Declaration in paragraph 8
refers to "experimental results set forth in the present application" but does
not direct us to the specific evidence or explain such evidence. Moreover,
Appellants have not compared the claimed invention with the closest prior
art (i.e., Maeshima). Appellants' argument of unexpected results is
premised on the low SAR chabazite catalyst being destroyed when used in a
high temperature exhaust gas (App. Br. 16). Claim 1, however, does not
require any temperature for the exhaust gas. As noted earlier in this
decision, Maeshima's economizer to lower the exhaust gas temperature to a
temperature between 200 and 500°C is not excluded by claim 1. Appellants'
Moini Declaration is not sufficient to overcome strong evidence of
obviousness provided by the Examiner.
On this record, we affirm the Examiner's § 103 rejection over
Maeshima in view of Maher, Famos and Ward. We further affirm the
Examiner's § 103 rejections (2) to (7) for the same reasons.
DECISION
The Examiner's decision is affirmed.
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)(l )(iv).
AFFIRMED
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