SAUDI BASIC INDUSTRIES CORPORATION

Patent Trials and Appeals Board

Oct 22, 2020

15689452 - (D) (P.T.A.B. Oct. 22, 2020)

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.
15/689,452 08/29/2017 Ashim Kumar Ghosh 12CHEM0044-US-CNT 7293
102091 7590 10/22/2020
Cantor Colburn LLP - SABIC Americas
20 Church Street
Hartford, CT 06103
EXAMINER
CHONG, JASON Y
ART UNIT PAPER NUMBER
1772
NOTIFICATION DATE DELIVERY MODE
10/22/2020 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):
usptopatentmail@cantorcolburn.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ASHIM KUMAR GHOSH,
MOHAMED ELBACCOUCH, MOHAMMAD SHAFIEI, and
MURALI GOPALAKRISHNAN

Appeal 2019-005578
Application 15/689,452
Technology Center 1700
Before BRIAN D. RANGE, DEBRA L. DENNETT, and
LILAN REN, Administrative Patent Judges.
DENNETT, Administrative Patent Judge.
DECISION ON APPEAL1
Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the
Examiner’s decision to reject claims 1–11. See Final Act. 1. We have
jurisdiction under 35 U.S.C. § 6(b).

1 In our Decision, we refer to the Specification (“Spec.”) of Application No.
15/689,452 filed August 29, 2017 (“the ’452 App.”); the Final Office Action
dated September 10, 2018 (“Final Act.”); the Appeal Brief filed February
11, 2019 (“Appeal Br.”); the Examiner’s Answer dated May 16, 2019
(“Ans.”); and the Reply Brief filed July 16, 2019 (“Reply Br.”).
2 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies the real party in interest as SAUDI
BASIC INDUSTRIES CORPORATION. Appeal Br. 2.
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We AFFIRM IN PART.
STATEMENT OF THE CASE
The ’452 Application relates to toluene methylation with
transalkylation of heavy aromatics for preparing xylene products. Spec. ¶ 1.
Para-xylene (p-xylene) is said to be particularly valuable as a precursor to
forming polyester fibers and resins. Id. ¶ 3. According to the ’452
Application, toluene methylation used in laboratory studies to produce
mixed xylene (o-, m-, and p-xylene) has technical hurdles and results in less
valuable C9+ aromatics byproducts, making the previously known process of
toluene methylation commercially unattractive. Id. ¶ 5.
Claim 1 is representative of the ’452 Application’s claims and is
reproduced below from the Claims Appendix of the Appeal Brief.
1. A method of producing a purified mixed xylene
comprising:
introducing toluene and methanol to an alkylation
reactor;
reacting the toluene and the methanol in the alkylation
reactor to form a hydrocarbon stream comprising a first mixed
xylene, wherein the alkylation reactor comprises an alkylation
catalyst;
separating the hydrocarbon stream into a toluene stream
and a separated C8+ stream;
introducing the toluene stream to a transalkylation reactor
with a transalkylation catalyst to produce a transalkylated
stream comprising a second mixed xylene;
adding the transalkylated stream to the hydrocarbon
stream; and
separating a C8 product stream comprising the purified
mixed xylene from the separated C8+ stream.
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REFERENCES
The Examiner relies on the following prior art:
Name Reference Date
Ghosh et al. (“Ghosh”) US 8,062,987 B2 Nov. 22, 2011
Haizmann et al.
(“Haizmann”)
US 2012/0271071 A1 Oct. 25, 2012
Ding et al. (“Ding”) US 2013/0267746 A1 Oct. 10, 2013

REJECTIONS
The Examiner rejects claims under 35 U.S.C. § 1033 as follows: (1)
claims 1 and 10 as unpatentable over Ding; (2) claims 2–7 and 11 as
unpatentable over Ding in view of Ghosh; and (3) claims 8 and 9 as
unpatentable over Ding in view of Haizmann. Final Act. 7–14.
OPINION
We review the appealed rejections for error based upon the issues
identified by Appellant and in light of the arguments and evidence produced
thereon. 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 [E]xaminer’s rejections.”). After considering the
evidence presented in this Appeal and each of Appellant’s arguments,
Appellant persuades us of reversible error in the Examiner’s rejection of
claims 4–7, but fails to persuade us of reversible error in the rejections of
claims 1–3, and 8–11.

3 Because this application was filed after the March 16, 2013, effective date
of the America Invents Act, we refer to the AIA version of the statute.

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Rejection of claims 1 and 10 as obvious over Ding
Regarding claim 1, the Examiner finds that Ding teaches the
limitations of claim 1 except for explicitly disclosing the step of adding the
transalkylated stream to the hydrocarbon stream. Final Act. 8. The
Examiner finds that Ding teaches subjecting a methylation production
stream (i.e., the claimed hydrocarbon stream) and a transalkylated product
stream to the same separation step in which toluene is separated from the
remaining C8+ aromatics and sent to the transalkylation step. Id. (citing Ding
¶ 25). The Examiner finds that Ding discloses separation and recovery of
benzene and toluene from the methylation effluent and the transalkylation
effluent, and that the recovered benzene and toluene can be sent to the
transalkylation step and the methylation step. Ans. 10 (citing Ding ¶¶ 24–
25). The Examiner finds that the claimed invention differs from Ding only
in that it requires combining the methylation effluent with the
transalkylation effluent prior to the toluene separation column. Id. at 13.
The Examiner reasons that one of ordinary skill in the art would reasonably
expect the same result of the separation step, whether the methylation
product stream and transalkylation stream enter the separation section
separately or in a combined stream, thus claim 1 is not patentably
distinguishable from Ding’s disclosure. Final Act. 8–9.
Appellant argues
Ding merely discloses the benzene and toluene from the reactor
effluent are subjected to a methylation step, which produces a
mixture of xylenes, and, in a transalkylation step, C9+ aromatics
from the reactor effluent or those derived from the methylation
step is subjected to transalkylation to yield a mixture of xylenes.
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Appeal Br. 4. Appellant contends that, based on Ding’s disclosure that
“effluents from the methylation step and transalkylation step share the same
separation step,” the skilled artisan “might at best consider directing the
effluents from the methylation step and transalkylation step [to] share the
same separation step in order to separate out their products.” Id. Appellant
provides an annotated version of Ding’s FIG. 4 with an asterisk added to
show “where it is believed that an artisan presented with Ding might at best
consider a shared separation step in order to separate their xylene from the
TM (methylation) and TA (transalkylation) steps from the benzene.” Id. at
5. Appellant’s annotated figure is reproduced below with the asterisk added
by Appellant circled in red:

Ding FIG. 4 shows a process for maximizing para-xylene production
by the integration of the methylation and transalkylation steps in accordance
with an embodiment of Ding’s invention. Ding. ¶ 11. TA represents
transalkylation, TM represent transmethylation, T represents toluene, B
represent benzene, X represents mixed xylene, PX represents para-xylene,
and C9A+ represents C9+ aromatics. Ding ¶¶ 15, 22.
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Appellant argues that subjecting effluents from a methylation step and
a transalkylation step to the same separation step does not meet the
requirements of claim 1. Appeal Br. 5. More specifically, Appellant urges
that claim 1 requires a portion of the hydrocarbon stream is directed to the
transalkylation reactor and a portion of the transalkylated stream is also
redirected/recycled back into the transalkylation reactor. Id. According to
Appellant, the application explains that the transalkylated stream can be
combined with the hydrocarbon stream and can be added to the toluene
separation column to introduce more xylene into the column. Id. Appellant
acknowledges that claim 1 does not require combination of the hydrocarbon
stream and the transalkylated stream prior to being added to a separation
unit. Reply Br. 4. Appellant contends that the inventive feature of adding
the transalkylated stream comprising the second mixed xylene to the
hydrocarbon stream and then adding the toluene separated from the
transalkylated stream back into the transalkylation reactor is not disclosed or
suggested by Ding. Id. at 4–5. Appellant argues that there is no motivation
in Ding to add these steps, thus no reasonable expectation of success without
consideration of the ’452 Application—which is barred by hindsight.
Appeal Br. 6.
Appellant’s position is not persuasive of reversible error.
Ding teaches that at least a portion of the methylated aromatic
hydrocarbon-enriched fraction created in the methylation step is subjected to
a transalkylation step to form paraxylene. Ding ¶ 15. Ding also teaches
that, in certain embodiments, a portion of benzene and toluene from the
methylation step is transferred to the transalkylation step. Id. ¶ 24. For this
to occur, as the Examiner explains, the methylated aromatic hydrocarbon-
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enriched fraction of Ding must be separated into a benzene and toluene
stream and a C8+ fraction. Ans. 10.
Ding teaches that the effluents from the methylation step and
transalkylation step share the same separation section. Id. ¶ 25. Thus, both
a hydrocarbon stream (the methylated aromatic hydrocarbon-enriched
fraction created in the methylation step) and a transalkylated stream are fed
to the same separation column. Claim 1 does not require the hydrocarbon
stream and the transalkylated stream to be combined prior to being added to
a separation unit. See Reply Br. 4. Ding teaches that benzene and toluene
are recovered and recycled from the transalkylation step. See Ding FIG. 1
(indicating the C8+ streams of methylation and transalkylation are combined
and C6, C7 are separated); FIGs. 4, 5 (indicating that all benzene and
toluene are recycled). The benzene and toluene, either mixed or separated,
are transferred to the methylation step and the transalkylation step. Id. ¶ 25.
Contrary to Appellant’s position (see Reply Br. 4–5), Ding thus discloses
adding the transalkylated stream to the hydrocarbon stream and then adding
the toluene separated from the transalkylated stream back into the
transalkylation reactor.
For the above reasons, Ding at least renders claim 1 obvious.
Appellant presents argument referring to claim 10, but the arguments
address claim 9 instead. See Ans. 14–15; Reply Br. 5. Thus, Appellant
offers no separate argument for patentability of claim 10. We sustain the
rejection of claim 10 for the reasons we provide above for claim 1.
Rejection of claims 2–7 and 11 as obvious over Ding in view of Ghosh
Claims 2–7 and 11 depend directly or indirectly from claim 1. Appeal
Br. 11–12 (Claims App.).
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Claims 2, 3, and 11
Claim 2 requires that the alkylation catalyst comprises a phosphorus
containing, medium pore, pentasil zeolite having a silica/alumina ratio of
greater than or equal to 200. Id. at 11. Claims 3 and 11 depend from claim
2. Id. Claims 3 and 11 require that phosphorus is present in an amount of
0.01 (claim 3) or 0.07 (claim 11) to 0.15 g per gram of zeolite. Id. at 11, 12.
With regard to claims 2, 3, and 11, the Examiner finds that Ding
discloses methylation (alkylation) in the presence of a zeolite catalyst such
as ZSM-5. Final Act. 9 (citing Ding ¶ 16). The Examiner relies on Ghosh
as teaching a phosphorus-modified ZSM-5 zeolite catalyst that is pretreated
with water to be used in alkylation of toluene with methanol, and that ZSM-
5 has the claimed properties. Id. at 9. The Examiner finds that Ghosh
discloses increasing para-xylene selectivity by modifying ZSM-5 zeolite
with phosphorus. Id. at 9–10.
The Examiner finds that Ghosh teaches the phosphorous-treated ZSM-
5 catalyst may contain 0.0001 to 0.15 g phosphorous per gram of zeolite
(claim 3) and about 0.007 to about 0.12 g phosphorus per gram of zeolite
(clam 11), which ranges overlap the claimed ranges. Final Act. 10, 12.
The Examiner concludes that it would have been obvious to one of
ordinary skill in the art at the time of the filing to modify Ding by treating
the ZSM-5 zeolite catalyst with phosphorus because such treatment will
increase the para-selectivity properties of the zeolite and improve para-
xylene selectivity. Id. at 10. The Examiner further concludes that the
modification would involve substitution of a known prior art methylation
catalyst for another known prior art methylation catalyst to improve a known
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process for the methylation of toluene with methanol to obtain predictable
results. Id.
In the Answer, the Examiner explains that Ding discloses a broad
range of zeolite frameworks that may be used as a catalyst in the methylation
step but does not provide specific details on the catalyst composition or the
preparation steps of such a catalyst. Ans. 15. According to the Examiner,
one skilled in the art, reading the disclosure of Ding, would look to other
prior art for information on workable zeolite catalysts and their preparation
in accordance with the guidance of Ding, and Ghosh exemplifies such a
known methylation catalyst having ZSM-5 framework zeolite. Id. The
Examiner also finds that Ding’s figures do not identify which catalyst and
process conditions (e.g. temperature, pressure, feed rate) were employed
and, therefore, do not provide meaningful information on the effect of the
catalysts suggested by Ding. Id. at 15–16.
Appellant argues that there is no motivation for one of ordinary skill
in the art to replace Ding’s catalyst with Ghosh’s because Ding achieves a
high amount of xylene in its product streams. Appeal Br. 8; Reply Br. 6.
Appellant contends that Ding discloses several specific examples of
catalysts, thus there is no need for one of ordinary skill to rely on Ghosh to
glean catalyst details. Reply Br. 6. Appellant urges that catalysis is
notoriously unpredictable as a further reason not to modify Ding with
Ghosh. Id. at 6–7.
Ding discloses a group of possible catalysts for alkylation, including
ZSM-5. Ding ¶¶ 16, 18. One of ordinary skill in the art in possession of
Ding would reasonably look to other art (such as Ghosh) for more
information on specific catalysts—a reason that would have prompted a
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person of ordinary skill in the relevant field to combine the elements in the
way the claimed new invention does. See KSR Int’l Co. v. Teleflex Inc., 550
U.S. 398, 418 (2007). “When there is a design need or market pressure to
solve a problem and there are a finite number of identified, predictable
solutions, a person of ordinary skill has good reason to pursue the known
options within his or her technical grasp.” Id. at 421. Here, a design need
existed to choose a specific catalyst for use in Ding’s method. The choice of
Ghosh’s ZSM-5 catalyst is the product of ordinary skill and common sense.
See id.
Appellant’s contention that catalysis is notoriously unpredictable does
not alter our opinion. See Reply Br. 6–7. “Our precedent, however, does
not require that the motivation be the best option, only that it be a suitable
option from which the prior art did not teach away.” Par Pharm., Inc. v.
TWI Pharm., Inc., 773 F.3d 1186, 1197–98 (Fed. Cir. 2014). “[A]
reasonable expectation of success, not absolute predictability” supports a
conclusion of obviousness. In re Longi, 759 F.2d 887, 897 (Fed. Cir. 1985).
Ding discloses use of, inter alia, a ZSM-5 zeolite catalyst, and Ghosh
discloses details of a ZSM-5 zeolite catalyst. Ding ¶ 16; Ghosh generally.
The Examiner’s finding that a skilled artisan would have a reasonable
expectation of success in substituting Ghosh’s ZSM-5 catalyst in Ding’s
method is therefore supported by the record before us.
Evidence of a motivation to combine prior art references “may flow
from the prior art references themselves, the knowledge of one of ordinary
skill in the art, or, in some cases, from the nature of the problem to be
solved.” Brown & Williamson Tobacco Corp. v. Philip Morris Inc., 229
F.3d 1120, 1125 (Fed. Cir. 2000). Although catalysis may have some
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unpredictability, “a given course of action often has simultaneous
advantages and disadvantages, and this does not necessarily obviate
motivation to combine.” Medichem, S.A. v. Rolabo, S.L., 437 Fed. 1157,
1165 (Fed. Cir. 2006) (citation omitted). One of ordinary skill in the art
would have known that selecting a specific catalyst involved some
unpredictability, but would reasonably turn to Ghosh, given its disclosure of
providing para-selective properties to the ZSM-5 zeolite catalyst by treating
it with phosphorus-containing compounds. See Ghosh 3:15–18. The fact
that the motivating benefit (improved para-selective properties) comes at the
expense of choosing a different catalyst from those disclosed generally in
Ding should not nullify its use as a basis to modify the disclosure of Ding
with the teachings of Ghosh. Winner Int’l Royalty Corp. v. Wang, 202 F.3d
1340, 1349 at n. 8 (Fed. Cir. 2000). “Instead, the benefits, both lost and
gained, should be weighed against one another.” Id. The Examiner
articulated reasoning has the requisite rational underpinning to support the
legal conclusion of obviousness of claims 2, 3, and 11. See In re Kahn, 441
F.3d 977, 9888 (Fed. Cir. 2006).
Claims 4–7
Claim 4 requires conversion of greater than or equal to 0.05 g of C9+
aromatics per gram of toluene in the alkylation reactor. Id. at 11. Claim 5
requires the purified mixed xylene comprises greater than or equal to 85
wt% p-xylene based on the total amount of mixed xylene. Id. Claims 6 and
7 require the selectivity of the alkylation catalyst for para-xylene to be
greater than or equal to 80 mol% (claim 6) or less than or equal to 75 mol%
(claim 7). Id.
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With regard to claims 4–7, the Examiner finds that Ding does not
explicitly disclose the claimed limitations regarding the production of C9+ in
the alkylation reactor (claim 4), the ratio of p-xylene based on the total
xylenes produced (claim 5), or catalyst selectivities for p-xylene (claims 6
and 7). Id. However, the Examiner finds that Ghosh teaches that a ZSM-5
zeolite catalyst that is modified with phosphorus allows for increased para-
xylene selectivity, and therefore it would have been obvious to one skilled in
the art to modify Ding by using a phosphorus-modified ZSM-5 catalyst, as
discussed above. Id. Specifically, the Examiner finds that Ding in view of
Ghosh discloses a similar process of alkylation of toluene with methanol as
the method recited in claim 1 under similar conditions including catalyst
(compare Ghosh 3:16–4:27 with Spec. ¶¶ 34–37), temperature (compare
Ding ¶ 16 with Spec. ¶ 19), and pressure (compare Ding ¶ 16 with Spec.
Table 4). Id. The Examiner finds that one of ordinary skill in the art would
have reasonably expected the process of Ding in view of Ghosh to function
the same as the process of alkylation recited in claims 4 and 5 and produce
the required results, absent evidence to the contrary. Id.
The Examiner finds that Ghosh is silent on the selectivity for para-
xylene, but discloses a similar catalyst to that claimed. Id. at 11–12. The
Examiner finds that Ghosh’s catalyst is reasonably expected to have a
selectivity range similar to that claimed in claims 6 and 7. Id. at 12.
Appellant argues that neither Ding nor Ghosh specifically disclose the
additional limitations in claims 4–7. Appeal Br. 8; Reply Br. 7. Appellant
contends that neither reference suggests the high para-xylene selectivities of
claims 6–8. Id. Instead, Appellant argues, the references merely disclose an
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amount of xylene produced (Ding) and the percentage toluene conversion
(Ghosh). Id.
Where a product is produced by a claimed process and prior art
products are produced by identical or substantially identical processes, the
PTO can require an applicant to prove that the prior art products do not
necessarily or inherently possess the characteristics of his claimed product.
In re Best, 562 F.2d 1252, 1256 (CCPA 1977). This is the doctrine that the
Examiner invokes in determining that one of ordinary skill in the art would
reasonably expect the process disclosed by Ding in view of Ghosh to
function the same as the alkylation process in claims 4 and 5 and produce
the claimed results.
Here, however, the Examiner finds that the processes are “similar,”
not identical or substantially identical. See Final Act. 11. In addition, the
use of inherency, a doctrine originally rooted in anticipation, must be
carefully circumscribed in the context of obviousness. See, e.g., In re
Rijckaert, 9 F.3d 1531, 1533–34 (Fed. Cir. 1993) (“The mere fact that a
certain thing may result from a given set of circumstances is not sufficient
[to establish inherency].” (internal quotation omitted)). “[T]he inherency of
an advantage and its obviousness are entirely different questions.
. . . Obviousness cannot be predicated on what is unknown.” In re Shetty,
566 F.2d 81, 86 (CCPA 1977) (quoting In re Spormann, 363 F.2d 444, 448
(1966)).
Our reviewing court and its predecessor established that the concept
of inherency must be limited when applied to obviousness, and is present
only when the limitation at issue is necessarily present or the “natural result”
of the combination of prior art elements. PAR Pharm., Inc. v. TWi Pharms.,
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Inc., 773 F.3d 1187, 1195–96 (Fed. Cir. 2014) (emphasis added). On the
record before us, we cannot say that the limitations of claims 4–7 are
necessarily present or the natural result of the combination of Ding and
Gosh. Therefore, we do not sustain the rejection of claims 4–7.
Rejection of claims 8 and 9 as obvious over Ding in view of Haizmann
Claim 8 depends from claim 1 and further requires separating the C8+
stream in a xylene column into the C8 product stream and a separated C9+
stream. See Appeal Br. 11 (Claims App.). Claim 9 depends from claim 8
and further requires separating the separated C9+ stream in a C9 separation
column into a C9 stream and a C10+ stream; and introducing the C9 stream to
the transalkylation reactor. Id. at 12.
Regarding claim 8, the Examiner finds that Ding discloses separating
a C8+ stream into a C8 product stream and a C9+ stream. Id. at 13. The
Examiner finds that Ding does not explicitly disclose that the separation
section comprises a xylene column. Final Act. 12. The Examiner relies on
Haizmann for teaching use of a xylene column to separate a fraction of
reformate to produce a stream comprising C8 aromatic hydrocarbons and a
different stream comprising C9, C10 and heavier aromatic hydrocarbons. Id.
(citing Haizmann ¶¶ 9, 18, 32). The Examiner views this disclosure as
teaching “separating a C8+ stream in a xylene column into the C8 product
stream and a separated C9+ stream.” Id.
The Examiner concludes that it would have been obvious to one of
ordinary skill in the art to modify Ding by separating the C8+ stream
produced from the methylation and transalkylation steps into a C8 product
stream and a C9+ stream by using a xylene column, as the method involves
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application of a known technique to operate a known process to yield
predictable results. Id. at 13.
Appellant argues only that Haizmann fails to cure the deficiency of
Ding identified in the discussion of claim 1. Appeal Br. 9.
Because we find no error in the Examiner’s rejection of claim 1 over
Ding, we sustain the rejection of claim 8 over Ding in view of Haizmann.
Regarding claim 9, the Examiner finds that Ding discloses sending a
C9+ stream to the transalkylation step to produce C8 aromatics, the reference
does not explicitly disclose separating the C9+ stream into a C9 stream and a
C10+ stream and introducing the C9 stream to the transalkylation reactor.
Final Act. 13.
The Examiner relies on Haizmann for teaching separating the C9+
stream to produce a trimethylbenzene-enriched fraction (a C9 stream) and a
C10 aromatic hydrocarbon-enriched fraction by using a distillation column,
which the Examiner identifies as a C9 separation column. Id. (citing
Haizmann ¶¶ 32, 38, Fig. 1). The Examiner finds that Haizmann discloses
sending the separated trimethylbenzene-enriched fraction to the
transalkylation step to produce C8 aromatics. Id. (citing Haizmann ¶ 33).
The Examiner cites Haizmann as teaching that transalkylation processes are
significantly more selective for transalkylating methyl group substituents of
an aromatic ring, compared to higher alkyl group substituents (e.g. ethyl,
propyl, and butyl), because higher alkyl groups are much more susceptible,
under transalkylation conditions, to being non-selectively dealkylated or
removed from the aromatic ring, thereby forming benzene and light alkene
hydrocarbons. Id. at 13–14 (citing Haizmann ¶¶ 9–11). The Examiner finds
that Haizmann teaches that the use of a methylated aromatic hydrocarbon-
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enriched fraction in the transalkylation is advantageous because it increases
production of para-xylene. Id. at 14 (citing Haizmann ¶ 27).
The Examiner determines
it would have been obvious to separate in a C9 separation column
a trimethylbenzene-enriched fraction (i.e. a C9 stream) from the
C9+ stream obtained from the xylene column, and send the
separated trimethylbenzene-enriched fraction to the
transalkylation step, as taught by Haizmann, because (i) Ding, in
view of Haizmann, teaches obtaining a C9+ stream which is then
used as a feed to a transalkylation to produce C8 aromatics, (ii)
Haizmann further teaches separating trimethylbenzene from a
C9+ stream and sending it to transalkylation increases
transalkylation performance and paraxylene selectivity, and (iii)
this involves application of a known technique of preparing a
transalkylation feed to improve a known transalkylation process
to yield predictable results.
Id.
Appellant argues that because Ding is completely silent to
separating a C9+ stream into a C9 stream and a C10+ stream, one skilled
in the art would have no motivation or suggestion to do so based on
Ding’s disclosure. Appeal Br. 7; Reply Br. 5. Appellant cites to
Ding’s disclosure that the invention is directed to a process “for
producing xylenes by using benzene, toluene and C9 plus aromatics”
and claim 1 of Ding recites “a transalkylation step that converts the C9
plus aromatics from the methylation step to C8 aromatics. Reply
Br. 5.
The Examiner relies on Haizmann, not Ding, for separating a
C9+ stream into a C9 stream and a C10+ stream. Final Act. 13.
Therefore, Appellant fails to address the Examiner’s rejection of claim
9 over Ding combined with Haizmann persuasively.
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We sustain the rejection of claim 9 as obvious over Ding in
view of Haizmann.
CONCLUSION
The Examiner’s decision to reject claims 1–3 and 8–11 is AFFIRMED
and claims 4–7 is REVERSED.
DECISION SUMMARY
In summary:
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 10 103 Ding 1, 10
2–7, 11 103 Ding, Ghosh 2, 3, 11 4–7
8, 9 103 Ding, Haizmann 8, 9
Overall
Outcome
1–3, 8–11 4–7

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 IN PART