Ex Parte Brok et al

Board of Patent Appeals and Interferences

Aug 10, 2009

10501240 (B.P.A.I. Aug. 10, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte THEODORUS JOHANNES BROK,
RUDOLF JOHANNES GROENEN, JEANINE MARIE KLINKENBIJL,
and MARIETTE CATHARINA KNAAP
____________

Appeal 2009-003712
Application 10/501,240
Technology Center 1700
____________

Decided: August 11, 2009
____________

Before CATHERINE Q. TIMM, ROMULO H. DELMENDO, and
JEFFREY B. ROBERTSON, Administrative Patent Judges.

DELMENDO, Administrative Patent Judge.

DECISION ON APPEAL
Appeal 2009-003712
Application 10/501,240

2
Appellants appeal under 35 U.S.C. § 134(a) from a final rejection of
claims 1-4, 9, 12-16, 20, and 23 (Appeal Brief filed August 13, 2008,
hereinafter “App. Br.,” at 2; Reply Brief filed October 13, 2008, hereinafter
“Reply Br.”; Final Office Action mailed March 13, 2008). We have
jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

STATEMENT OF THE CASE
Appellants state that the claimed invention “relates to a process for
removing carbon dioxide and optionally hydrogen sul[f]ide and/or COS
[carbonyl sulfide] from a gas stream . . . by washing the gas with an aqueous
washing solution containing water, sulfolane and a secondary or tertiary
amine derived from ethanol amine [e.g., methyldiethanolamine (MDEA)]”
(Specification, hereinafter “Spec.,” 1, ll. 1-8 and 1, l. 29 to 2, l. 3).
According to Appellants, “the addition of a few wt% of piperazine [to an
aqueous mixture of, e.g., MDEA and cyclotetramethylene-sulfone
(sulfolane)] results in a clear improvement of the kinetics of the system,
resulting in a lower liquid/gas ratio, which may result in a smaller design of
the plant (absorber as well as regenerator)” (Spec. 2, ll. 10-13 and 23-27).
Claims 1 and 15, the only independent claims, read as follows:
1. A process for the removal of carbon dioxide from a
gas stream containing carbon dioxide by washing the gas
stream with an aqueous washing solution containing between
15 and 45 parts by weight water, between 15 and 40 parts by
weight sulfolane and between 30 and 60 parts by weight of an
amine selected from the group of amines consisting of MEA,
DEA, TEA, DIPA and MDEA, wherein the parts by weights are
based on the amounts of water, sulfolane and amine together
being 100 parts by weight, and, further, wherein the aqueous
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washing solution contains piperazine in an amount in the range
of from 0.7 mol/1 to 0.9 mol/1.

15. An absorbent liquid containing between 15 and 45
parts by weight water, between 15 and 40 parts by weight
sulfolane and between 30 and 60 parts by weight of an amine
selected from the group of amines consisting of MEA, DEA,
TEA, DIPA and MDEA, wherein the parts by weights are based
on the amounts of water, sulfolane and amine together being
100 parts by weight, and, further, wherein the aqueous washing
solution contains piperazine in an amount in the range of from
0.7 mol/l to 0.9 mol./l.
(App. Br. 9 and 10, Claims App’x.)
The Examiner relied upon the following as evidence of
unpatentability (Examiner’s Answer mailed September 4, 2008, hereinafter
“Ans.,” 2-3):
Wagner US 4,997,630 Mar. 5, 1991
Appellants rely on the following as evidence of nonobviousness (App.
Br. 11, Evidence App’x):
Appl US 4,336,233 June 22, 1982
The Examiner rejected claims 1-4, 9, 12-16, 20, and 23 under 35
U.S.C. § 102(b) as anticipated by, or in the alternative, under 35 U.S.C. §
103(a) as obvious over Wagner (Ans. 2-6).

ISSUES
With respect to the anticipation rejection of claim 1, the Examiner
asserts that Wagner “disclose[s] a process for the removal of CO2 and/or H2S
from gases by means of an aqueous methyldiethanolamine-containing
absorption liquid [i.e., washing solution]” wherein the “aqueous absorption
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liquid contain[s] from 20 to 70 preferably from 30 to 65, and in particular
from 40 to 60 wt% of methyldiethanolamine [MDEA]” (Ans. 3).
Furthermore, the Examiner finds that Wagner’s washing solution can
additionally contain sulfolane “in an amount of from 1 to 60, preferably
from 10 to 50, [and] in particular from 20 to 40 wt%” and that “the balance
of [the] aqueous washing liquid . . . would be water, which reads on the
limitation as claimed” (id. at 4). With regard to piperazine, the Examiner
finds that Wagner “disclose[s] advantageously, the aqueous
methylenediethanolamine solution used additionally contains from 0.05 to 1,
in particular from 0.1 to 0.8, and especially from 0.1 to 0.6 mol/l of . . .
piperazine” (id.).
In the alternative, the Examiner asserts that “it would [have been]
obvious to have piperazine to be 0.7 mol/l to 0.9 mol/l because [the] broad
range of 0.05 to 1 mol/l [disclosed in the prior art] includes the narrow range
of 0.7 mol/l to 0.9 mol/l” (id.).
Appellants, on the other hand, contend that the Examiner erred in
finding anticipation because Wagner “does not teach each and every element
of the unique washing solution recited in the present claims with sufficient
specificity” (Reply Br. 4). In particular, Appellants assert that Wagner “does
not teach [the] concentration range for water specified in the present claims,
and in the sole specific example of an aqueous absorption solution, employs
a water concentration outside of the range specified in the present claims”
(id. at 3). According to Appellants, “Wagner . . . teaches three possible
concentration ranges for MDEA . . . and three possible concentration ranges
for a physical solvent . . . if a physical solvent is even used” (id.).
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With respect to the Examiner’s obviousness rejection, Appellants
contend that “the prior art as a whole teaches away from the aqueous
washing solution employed in the process recited in Appellant’s [sic]
claims” (id. at 4). Appellants assert that Appl, which is discussed in the
Specification at page 3, teaches that “only very dilute aqueous solutions can
be used together with piperazine, because of the formation of piperazine
carbamate” (Reply Br. 4; App. Br. 7). Appellants contend that, despite
Appl’s teachings, they “have surprisingly found that such limitations do not
occur when mixtures of water/sulfolane are used in certain proportions with
piperazine and MDEA” (Reply Br. 4).
Thus, the issues arising from the contentions of the Examiner and
Appellants are:
Have Appellants shown reversible error in the Examiner’s finding that
Wagner discloses the concentration ranges of components of a washing
solution with sufficient specificity to support an anticipation rejection of the
claimed subject matter?
If so, have Appellants shown reversible error in the Examiner’s
conclusion of obviousness as to claim 1 on the basis that Appl would have
taught away from the claimed invention?
Have Appellants shown reversible error in the Examiner’s
obviousness rejection by showing persuasive evidence of unexpected
results?

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FINDINGS OF FACT (“FF”)
1. Wagner discloses a process for “removal of CO2 and/or H2S
from gases” using “an aqueous absorption liquid containing
from 20 to 70, preferably from 30 to 65, and in particular from
40 to 60, % by weight of methyldiethanolamine [MDEA]” (col.
1, ll. 8-9; col. 2, ll. 30-32).
2. In an embodiment, Wagner discloses that “the aqueous
methyldiethanolamine [MDEA] solution used additionally
contains from 0.05 to 1, in particular from 0.1 to 0.8, and
especially from 0.1 to 0.6, mole/l of . . . piperazine” (col. 2, ll.
36-43).
3. Wagner discloses that “[t]he aqueous absorption liquid
containing from 20 to 70% by weight of methyldiethanolamine
[MDEA] can additionally contain a physical solvent,” e.g.,
tetramethylene sulfone (i.e., sulfolane) “in an amount of from 1
to 60, preferably from 10 to 50, [and] in particular from 20 to
40, % by weight” (col. 2, ll. 44-54).
4. In a sole example, Wagner discloses an absorption liquid
comprising “a 50% strength by weight aqueous
methyldiethanolamine [MDEA] solution” (col. 6, ll. 56-59).
5. Appl discloses “that amongst the industrially used physical
solvents, e.g. methanol, mixtures of
cyclotetramethylenesulfone, DIPA and water (Sulfinol ®),
NMP and dimethyl ethers of polyethylene glycols (Selexol ®),
only very dilute aqueous solutions can be used together with
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piperazine, because of the formation of piperazine carbamate”
(col. 3, ll. 29-35).

PRINCIPLES OF LAW
“Anticipation requires a showing that each limitation of a claim is
found in a single reference, either expressly or inherently.” Atofina v. Great
Lakes Chemical Corp., 441 F.3d 991, 999 (Fed. Cir. 2006).
“In cases involving overlapping ranges, we and our predecessor court
have consistently held that even a slight overlap in range establishes a prima
facie case of obviousness.” In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir.
2003).
“A known or obvious composition does not become patentable simply
because it has been described as somewhat inferior to some other product for
the same use.” In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994).

ANALYSIS
Anticipation of claims 1-4, 9, 12-16, 20, and 23
Appellants have shown reversible error in the Examiner’s finding that
Wagner anticipates the claimed invention. Table 1 below compares the
concentration ranges of the components of the claimed washing solution
with those of Wagner’s washing solution (FF 1-3):

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Component Claims 1
and 15
Wagner
(broadest)
Wagner
(preferred)
Wagner
(most
preferred)
MDEA wt% 30-60 20-70 30-65 40-60
sulfolane (wt%) 15-40 1-60 10-50 20-40
water (wt%) 15-45 balance balance balance
Piperazine (mol/l) 0.7-0.9 0.05-1.0 0.1-0.8 0.1-0.6
Table 1.
(Table 1 summarizes the ranges recited in claims 1 and 15 as well as the
ranges disclosed in Wagner.)
As seen in Table 1, Wagner does disclose solutions comprising
MDEA, sulfolane, and piperazine in concentration ranges that overlap the
claimed ranges. But each of the four broadest disclosed ranges for MDEA,
sulfolane, water, and piperazine includes concentrations that fall outside the
ranges recited in claims 1 and 15. The same is true for Wagner’s preferred
ranges. In addition, although Wagner’s “most preferred” ranges of MDEA
and sulfolane are within the claimed ranges, at least the “most preferred”
range of piperazine is completely outside the claimed range. Furthermore,
Wagner does not disclose any working example describing specific
concentrations within the claimed ranges (FF 4).
Thus, one of ordinary skill in the art would have had to resort to
picking and choosing from among Wagner’s disclosed ranges to arrive at a
washing solution having components within the claimed ranges.
Accordingly, Wagner does not describe the claimed range with sufficient
specificity to anticipate. See Atofina, 441 F.3d at 999-1000.

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Obviousness of Claims 1-4, 9, 12-16, 20, and 23
Appellants argue the appealed claims together. Accordingly, we
select claim 1 as representative and confine our discussion to this selected
claim. See 37 C.F.R. § 41.37(c)(1)(vii).
The Examiner’s obviousness rejection stands on different footing.
Regarding this rejection, we agree with the Examiner that the claimed
subject matter would have been obvious to one of ordinary skill in the art
over Wagner (Ans. 6; FF 1-3). As discussed above, Wagner’s disclosed
“broadest” and “preferred” ranges of MDEA, sulfolane, and piperazine
overlap the claimed ranges. With respect to the range for water, Appellants
have not shown error in the Examiner’s finding that the prior art range for
water overlaps the range recited in claim 1. Indeed, Appellants merely state
that “the ‘balance’ of water would . . . vary widely, and at most would only
partially overlap the specific concentration range for water recited in the
present claims” (App. Br. 6). Under these circumstances, we discern no
error in the Examiner’s prima facie case of obviousness. In re Peterson, 315
F.3d at 1329.
We next consider whether Appellants have provided a showing of
criticality or other evidence to rebut the Examiner’s prima facie case.
Appellants contend that Appl teaches away from the claimed washing
solution because Appl states that “only very dilute aqueous solutions can be
used together with piperazine, because of the formation of piperazine
carbamate” (FF 5).
This contention lacks persuasive merit. First, claim 1 does not
exclude carbamates. Second, Appellants have not directed us to any
experimental evidence that they unexpectedly avoid the problem of
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carbamates. Third, while Appl appears to disclose that “only very dilute
aqueous solutions can be used” (FF 5), Wagner’s later-filed disclosure states
that a washing solution comprising non-dilute aqueous solutions may be
used (FF 1-3). Thus, Appellants have not shown any discovery beyond what
would have been expected from the prior art. In re Gurley, 27 F.3d at 553.

CONCLUSION
Appellants have shown reversible error in the Examiner’s finding that
Wagner describes the claimed subject matter with sufficient specificity to
support an anticipation rejection.
However, Appellants have not shown reversible error in the
Examiner’s obviousness conclusion as to claim 1 on the basis that Appl
would have taught away from the claimed invention.
Also, Appellants have not shown reversible error in the Examiner’s
rejection of claim 1 with any persuasive evidence of unexpected results.

DECISION
Accordingly, we reverse the Examiner’s decision to reject claims 1-4,
9, 12-16, 20, and 23 under 35 U.S.C. § 102(b) as anticipated by Wagner.
We affirm, however, the Examiner’s decision to reject claims 1-4, 9, 12-16,
20, and 23 under 35 U.S.C. § 103(a) as unpatentable over Wagner.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(v).

AFFIRMED

Appeal 2009-003712
Application 10/501,240

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