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 .
Claim Status
The claims are not significantly amended, but several new claims are added.
Response to Arguments
Applicant's arguments filed 3/17/26 have been fully considered but they are not persuasive.
Pages 7-8 argue the following:
On pages 6 and 7 of the Office Action, the examiner characterizes the disclosures in Wang, as follows:
"C02+ 2-OOCCHCH3NH2- = -OOCCHCH3NHCOO- + -OOCCHCH3NH3+
(seepage 43). (emphasis added)
In the equation above, the second compound loses a hydrogen from "-NH2-" to make "-NH-", which can be considered a deprotonating-step of the carbamate group as described by Claim 15."
The examiner refers to 2 mole of the amino acid group on the left hand side of the equation being converted to: i) a first amino acid, on the right hand side, that is deprotonated, and ii) a second amino acid, on the right hand side, that is protonated. In other words, the examiner has identified the amine absorption reaction as a deprotonation reaction.
In contrast, claim 15 recites "carbon dioxide in the gas stream reacts with the amino acid derivative and adds a carbonate group to the amino group of the amino acid derivative to form a catalytic intermediate having a carbamate", and " wherein the contacting step is carried out under alkaline conditions so that the catalytic intermediate deprotonates". The examiner's assertion that Wang discloses deprotonation of the intermediate catalyst having a carbamate group is incorrect. The examiner is asserting deprotonation of amine in an absorption reaction is deprotonation of the catalytic intermediate which has a carbamate group, yet there is no possible way for a person skilled in the art to reach this process in view of Wang.
Deprotonation of the intermediate catalyst according to claim 15 is illustrated moving from right to left in Step 2 in Examples One and Two of the present specification (see Table 1 reproduced below). Contrary to the examiner's assertion, Wang fails to teach deprotonation of the carbamate group as defined in claim 15. On this basis, independent claim 15 is not obvious in view of Wang.
The remarks are respectfully not persuasive. As mentioned in the rejection, this formation was disparaged by the Wang reference and Wang states that because of this, the reaction proceeds to the equation on page 45 instead.
Next, the remarks argue the following on page 9:
In addition, the examiner asserts: "Wang explains that the first reaction has low stability (see page 43, last line) and therefore, the reaction proceeds to the reaction shown on page 45, which shows:
-OOCCHCH3NHCOO- + H2O = -OOCCHCH3NH2 + HCO3- (see equate on
page 45). (emphasis added)
This can be considered a hydrolysis step of the carbamate group, which produces
a bicarbonate and regenerates the amino acid."
However, the examiner omits that the zwitterion amino acid, namely -OOCCHCH3NH3+ is in the solution, and the text on page 45 of Wang describes that the zwitterion amino acid, and amino acid comprising carbamate, are in equilibrium with the bicarbonate. The text at the top of page 46 of Wang, and the diagram on page 46, extracted below, also shows that the zwitterion amino acid and the amino acid decompose to generate 2 mole of amino acid and carbon dioxide. This represents a generic amine based absorption and heat driven desorption reaction.
*see the figure on page 10*
In other words, Wang teaches that it is decomposition of the combination of bicarbonate, zwitterion amino acid, and amino acid derivative, all in solution, that are required to regenerate 2 mole of the amino acid derivative.
Importantly, the absorption and desorption steps in Wang are carried out in separate cycles/steps, see for example the text in section 2.2 on page 42 of Wang and the last paragraph on page 46 of Wang. This clearly shows that the amine based absorbent is operating as an absorbent and not as a catalyst as defined by the present disclosure.
In contrast, according the claim 15, during the contacting (absorbing) step, an amino acid derivative of N-substituted amino compounds absorbs carbon dioxide and forms a catalytic intermediate having a carbamate group, and then during the contacting (absorbing) step the carbamate group is deprotonated and hydrolysed to form carbonates (thus acting as a catalyst and not an absorbent) by the presence of a high concentration of potassium carbonate. The present disclosure enables carbon dioxide, in the form of a bicarbonate, to be "unbound" from the catalytic intermediate during the contacting (absorbing) step which regenerates the catalyst during the contacting step. This is not possible from the teachings in the prior art cited by the examiner.
Specifically, Wang teaches an absorption reaction and a desorption reaction that are carried out separately from each, other in separate cycles. It is not possible for a person skilled in the art on reading Wang to devise a process in which an amino acid derivative of N-substituted amino compounds absorbs carbon dioxide forms a catalytic intermediate having a carbamate, which is then deprotonated and hydrolysed to regenerate the catalyst and produce a bicarbonate in the contacting step (absorbing step) as taught by the present disclosure. On this additional basis, independent claim 15 is not obvious in view of Wang.
The remarks are respectfully not persuasive. Wang explains on page 45 that after the absorption step, which makes bicarbonate, a bicarbonate decomposition step was performed (page 45), which is used to “explore the CO2 desorption performance and examine the mechanism of CO2 desorption” (page 45, right col, para. 2). Therefore, the decomposition is used to analyze the system used in desorption, but is respectfully not the path of desorption used since desorption, as shown I the figure at page 45, already generates bicarbonate.
Next, the remarks argue the following on page 11:
The inventors have found that the presence of a base, namely potassium carbonate, in high concentrations, from 30 to 60 wt% according to the present disclosure not only thermodynamically favours the absorption of carbon dioxide to form a catalytic intermediate that has absorbed carbon dioxide, but the high concentration of the carbonate in solution also deprotonates and hydrolyses the intermediate catalyst. Wang fails to teach this benefit. On this basis, independent claim 15 is not obvious in view of Wang.
In the second paragraph on page 8 of the office action, the examiner acknowledges "Wang does not teach that the base used is a potassium carbonate used in a concentration range of 30- 60wt% in an aqueous solvent." and simply refers to the KR '099 as disclosing this feature. However, KR '099 does not disclose this feature, and does not suggest or teach why this feature is important. Specifically, the text refers to components A, B and C which appear to refer an amino acid (A), an amine (B), and water (C). The inclusion of K or Na seems to me to be practically limited to that which is required to form the amine acid salt.
The text bridging pages 3 and 4 also refers to a formula (((A+B)/(A+B+C)) x 100 and the inclusion of K and other species in the description of the elements of B. However, this does not amount to a teaching of a base solution having as potassium carbonate from the 30 to 60 wt%.
In addition, the process in KR '099 relies on separate absorbing and desorbing steps, representing use of the amine compound as absorbent, and not as a catalyst as taught by the present disclosure. That is to say, KR '099 does not overcome the failure of Wang of not disclosing or teaching that N-substituted amino compounds (ie an amino acid derivative) reacts with carbon dioxide acts as a catalytic intermediate having a carbamate, wherein the contacting (absorbing) step is carried out under alkaline conditions so that the catalytic intermediate deprotonates and the carbamate group undergoes hydrolysis which produces a bicarbonate and regenerates the amino acid derivative during the contacting step. On this basis, KR '099 has not further contribution to Wang and the present disclosure is not obvious in view of the Wang and KR '099.
The remarks are respectfully not persuasive. Wang does employ use of a base in their process. Specifically, Wang teaches use of NaOH, a strong base, in their composition (see section 2.1). Wang does not teach use of a potassium carbonate base in a concentration of 30-60wt%. KR ‘099 and Park were used to disclose this feature. KR ‘099 describes combining various bases with a CO2 absorbent that can include amino acids, such as alanine, serine or arginine (see office action, page 8). The different bases combined with the absorbent can include NaOH, KOH, H2CO3, Na2CO3 or NaHCO3 (see OA, page 8). Therefore, it would have been obvious to one skilled in the art to substitute the NaOH of Wang by its functional equivalent potassium carbonate, as taught by KR “099 with expected success. See MPEP 2144.06.
Next, the remarks argue the following:
The examiner also cites Park for the reason that it discloses an absorption solution containing 30wt% K2C03 (potassium carbonate). Park discloses using a potassium carbonate absorption process in which amine is used to both increase the solvent C02 storage capacity and speed up the absorption and desorption steps. Carbon dioxide is absorbed by the solution occurred at 70°C, and desorption was driven from the amine and carbonate solution at 90°C. See for example, the ABSTRACT and text at line 26 of the left column on page 127, and the line 11 of the right column of page 127. Park does not suggest that the process operates at an increased rate due to the amine species acting catalytically, rather the amine species simply acts as an absorbent. That is to say, Park does not suggest that a catalytic intermediate having a carbamate group can be deprotonated and be hydrolysed in accordance with the present disclosure. On this basis, Park and KR '099 do not address the failing of Wang.
At line 13 of page 6 of the office action, the examiner acknowledges that Wang "does not specifically teach that the N-substituted amino compound is an amino acid." and instead Wang references to another publication, HOOK, as teaching carbon dioxide can be thermally volatilised from solutions containing bicarbonate precipitant, dissolved carbonate and N-substituted amino compounds. However, this does not address the failing of Wang to teach that an amino acid derivative of N-substituted amino compounds can react with carbon dioxide during the contacting step and form a catalytic intermediate having a carbamate, and then during the contacting step have the carbamate group deprotonated and hydrolysed to form carbonates (thus acting as a catalyst and not an absorbent) by the presence of a high concentration of potassium carbonate in solution as taught by the present disclosure.
In addition, Park teaches absorption reaction and desorption reaction that are carried out in separately from each other in separate cycles, see the paragraph bridging the left and right hand columns on page 127. That is to say, Park does not overcome the failure of Wang and KR '099 of not disclosing or teaching that an amino acid derivative of N-substituted amino compounds can absorb carbon oxide to form a catalytic intermediate having a carbamate, wherein the absorbing step is carried out under alkaline conditions so that the catalytic intermediate deprotonates and the carbamate group undergoes hydrolysis which produces a bicarbonate and regenerates the amino acid derivative during the contacting (absorbing) step. On this additional basis, the present disclosure is not obvious in view of Wang, KR '099, and Park.
The remarks are respectfully not persuasive. The remarks state that Park does not describe the same mechanism described by Wang and the claims, which describe a catalytic intermediate having a carbamate group that is deprotonated and hydrolyzed (as described above). Although Park is silent on the mechanism, this feature is already taught by the primary reference above.
As to the issue at page 6, line 13, Wang does teach the feature of using an amino compound that reacts with CO2 to form a catalytic intermediate having a carbamate and then deprotonated and hydrolyzing to form a carbonate (see above). Th potassium carbonate feature relies on a different reference, as discussed above.
As to the entire system of the Park reference, this reference was relied upon for the limited teaching of the potassium carbonate concentration in water. Park describes use of an aqueous solvent for use in CO2 capture (title). Pak explains that when combining K2CO3 with amino acid salts, the absorptivity rate may increase (see Introduction, col. 2, lines 5-6). As to the amount, Park explains that in experimental tests, a concentration of 30wt% K2CO3 in water was effective (see section 1, para. 1).
Applicant argues that Park does not teach that the amino acid derivative of N-substituted amino compounds can absorb CO2 to form a catalytic intermediate having a carmate, wherein the absorption step is carried out under alkaline conditions so that the catalytic intermediate deprotonates and the carbamate group undergoes hydrolysis which produces a bicarbonate and regenerates the amino acid derivative during the contacting (absorbing) step. These features are already disclosed by the other references. Park is relied on for the limited teaching of K2CO3 concentration.
Next, page 13 argues the following:
The examiner asserts it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a N-substituted amino acid, as taught by Liu.
Liu suggests the amino acids is modified by introducing an isopropyl substitutent at the a- amino group enhanced carbon dioxide absorption, see lines 1 and 2 of the left column on page 11307. The teaching in Liu are about select an N-substituent that enhances absorption rate. However, the process disclosed in Liu use the amino acids as an absorbent and not as a catalyst. Moreover, the text pages 11308 and 11309 make it clear that the absorption and desorption steps are carried separately.
Therefore, Liu does not overcome the failure of Wang, KR '099 and Park of not disclosing or teaching that an amino acid derivative of N-substituted amino compounds reacts with carbon dioxide to produce a catalytic intermediate having a carbamate group, and then also during the contacting step the carbamate group is deprotonated and the intermediate catalyst hydrolysed to form carbonates (thus acting as a catalyst and not an absorbent), by the presence of a high concentration of potassium carbonate in solution, as taught by the present disclosure. On this basis, independent claim 15 is not obvious in view of the combination of Wang, KR '009, Park and Liu.
The remarks are respectfully not persuasive because Liu is relied on for the limited teaching that an amino acid is an N-substituted amino acid. As to the use of the amino acids as absorbents, it is respectfully argued that the use of the amino acids to absorb and then desorb is effectively the same as the claimed process. That is, the references use the same compounds in the same way. As to the absorption and desorption steps carried out separately, it seems that these are performed separately in the claims as well. That is, the process absorbs CO2 and the desorbs it in the form of a carbonate.
As to the feature: “an amino acid derivative of N-substituted amino compounds reacts with carbon dioxide to produce a catalytic intermediate having a carbamate group, and then also during the contacting step the carbamate group is deprotonated and the intermediate catalyst hydrolysed to form carbonates (thus acting as a catalyst and not an absorbent), by the presence of a high concentration of potassium carbonate in solution”, these features are taught by the prior references.
The remarks then argue on pages 13-14, the following:
Additional Benefits
The reactions identified by the examiner in Wang (highlighted above) use a 2:1 molar ratio of amino acid derivatives to carbon dioxide, see line 9 of page 45 of Wang. In contrast, one of the advantages this provides is that Steps 1, 2 and 3 occur at a 1:1 molar ratio of amino acid to carbon dioxide. In other words, the contacting step of the present disclosure requires half as much amino acid derivative (catalyst) as the process described in Wang. This advantage is by no means disclosed or suggested in Wang. On this basis, independent claim 15 is not obvious. This failing of Wang is not overcome by any one of KR '009, Park and Liu.
The text on page 45 of Wang teaches, and the reaction at the top of page 47 of Wang, discloses that the bicarbonate, whether dissolved or as a precipitant, carbonate (in solution) and the amino acid are then be heated together to drive off carbon dioxide to form a rich carbon dioxide
gas stream and regenerate the amino acid. Moreover, Wang, KR '009, Park and Liu rely on heating the solvent solution to regenerate the amino acid absorbent in solution.
In contrast, as stated in paragraph [0009] of the present specification: "One of the advantages of the solvent solution is that little or no heating is required to regenerate the amino acid derivative in this cycle and during the regeneration of the solvent solution". This is because the carbamate group of the intermediate is deprotonated and undergoes hydrolysis to regenerate the catalyst under alkaline conditions. This allows the precipitant, namely potassium bicarbonate to be separated from the solution containing the regenerated catalyst, and the precipitant stored or treated when it is cost effective to do so. This is benefit is not possible using the process disclosed in Wang, and the teachings in KR'009, Park and Liu do not overcome the failings of Wang. On this basis, independent claim 15 is not obvious.
The remarks are respectfully not persuasive. The ratio described in the remarks are not features found in Claim 15. Therefore, the remarks are outside the scope of the claim. Next, the remarks argue the heating feature, but again this is outside of the scope of the claim.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 15, 16, 17, 24, 26, 30, 31, 32, 33, 34, 35, 42 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang “Phase Change amino acid salt separates into CO2-rich and CO2-lean phases upon interacting with CO2”, attached, and in view of KR102069099 and in view of Park “Screening test for aqueous solvents used in CO2 capture. . “, and in view of Liu “Equimolar CO2 Capture by N-substituted Amino Acid Salts and Subsequent Conversion”.
Wang describes a CO2 capture process (see introduction, para. 2-3), which uses a CO2 absorption solution to sequester the gas (Introduction, para. 3). Wang explains that “amino acids are of great interest. . . for CO2 capture” (Introduction, para. 4). Therefore, in their process, Wang combines an amino acid (see section 2.1, which uses alanine, arginine, lsine and serine, which are all amino acids) with NaOH in water (deuterium oxide is water) (section 2.1, para. 1). This solution is used to absorb CO2 (see section 2.2). In some embodiments, Wang teaches that in the prior art, citing to Hook, that the amino absorption solution that can be used here can be an N-methyl-substituted 2-aminoethanol (page 45, line 36), but Wang does not specifically teach that the N-substituted amino compound is an amino acid.
As to the alkali salt feature, Wang shows in their NMR analysis that the alanaine contains Na (Fig. 2). This can be considered an inorganic alkali salt of the amino acid.
CO2 absorption is performed in a reactor (see section 2.2), which can be considered an absorber vessel. A precipitate was produced between the amino acid and the CO2 (section 2.2). As to the reaction mechanism, Wang analyzes the reaction and describes the reaction process as follows: the alanine solution reacted with CO2 to form Ala carbamate (-OOCCHCH3NHCOO-) (see section 3, para. 2, lines 5-6).
In Claim 15, lines 7-8, the claims describe that the CO2 reacts with the amino acid and then “adds a carbonate group to the amino group”, which should be COOO, but table 1 of the current specification shows that in step 1, CO2- is added to the amino acid group by adding a COO- group (see table 1 of the specification). Therefore, the carbonate group of Claim 15 will be treated as a COO- group.
Similarly, in the mechanism of Wang, after CO2 and alanine react, a COO- group is added to the compound (see page 43, right col, formula in last para).
As mentioned above, the process of absorption takes place in the presence of NaOH (see section 2.1). Therefore, the reaction conditions are considered alkaline.
The first reaction is:
CO2 + 2-OOCCHCH3NH2- = -OOCCHCH3NHCOO- + -OOCCHCH3NH3+ (see page 43).
In the equation above, the second compound loses a hydrogen from “-NH2-“ to make “-NH-“, which can be considered a deprotonating-step of the carbamate group as described by Claim 15.
Wang explains that the first reaction has low stability (see page 43, last line) and therefore, the reaction proceeds to the reaction shown on page 45, which shows:
-OOCCHCH3NHCOO- + H2O = -OOCCHCH3NH2 + HCO3- (see equate on page 45).
This can be considered a hydrolysis step of the carbamate group, which produces a bicarbonate and regenerates the amino acid.
As to the amino acid being a catalyst, since the amino acid used goes back to the same composition after the reaction, after it is used to facilitate the reaction, then it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that this can be considered a catalyst.
As to the bicarbonate being an alkali precipitate, Wang teaches that the precipitate can include bicarbonate (page 43, right col, lines 16-17 and line 3-5, where NaHCO3 is in the milky phase, but less so in the clear phase). As t the bicarbonate being an alkali, Wang teaches formation of NaHCO3 (page 43, right col, lines 6-7).
Wang does not teach that the base used is a potassium carbonate used in a concentration range of 30-60wt% in an aqueous solvent.
As to the use of potassium carbonate, KR ‘099 teaches an absorbent used for separating CO2 from a gas mixture (title). The absorbent mixture is combined with a second compound, which can be NaOH, KOH, K2CO3, Na2CO3 or NaHCO3 (page 3, “step (a), para. 4”). The absorbent can include amino acids, such as alanine, serine, arginine (page 3, last para).
It would have been obvious to one skilled in the art to substitute the NaOH of Wang
by its functional equivalent potassium carbonate, as taught by KR “099 with expected success. See MPEP 2144.06.
As to the concentration of potassium carbonate in water, Park describes use of an aqueous solvent for use in CO2 capture (title). Pak explains that when combining K2CO3 with amino acid salts, the absorptivity rate may increase (see Introduction, col. 2, lines 5-6). As to the amount, Park explains that in experimental tests, a concentration of 30wt% K2CO3 in water was effective (see section 1, para. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ K2CO3 in an amount of 30 wt%, as taught by Park for use with the K2CO3 of KR ‘099 in the absorption solution of Wang because this amount of K2CO3 would lead to predictable CO2 sequestration results.
As to the amino acid being N-substituted, the references do not specifically describe this.
Liu describes CO2 Capture (title). The reference explains in the background that conventional technology for the industrial capture of CO2 is known to employ amines (page 11306, left col, para. 2). Some of these amines include various amino acids (see Table 1). CO2 sequestration is known to form carbamate salts (pg 11306, right col, last para). As to the use of an N-substituted amino acid, Liu explains that to their “delight, introducing isopropyl substituent at the alpha-amino group greatly enhanced the CO2 capacity” (page 11307, left col, para. 1). Liu explains that various substitutions vary the CO2 absorption (see table 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a N-substituted amino acid, as taught by Liu for use with the CO2 absorption solution of Wang, KR ‘099 and Park because Liu explains that use of a N-substituted amino acids are known to greatly enhance the CO2 capacity of the adsorption solution.
As to Claim 16, Wang teaches that the reaction is maintained at a temperature of 313K during adsorption, then heated to 393K during desorption and then cooled back down to 313K for the next absorption-desorption cycle (see section 2.2).
As to Claim 17, Wang teaches cooling the absorption solution in a water bath (see section 2.2).
As to Claim 24, Wang teaches in one example that the absorption phase can be performed at 313K (see section 2.2) or 39.85 degrees C. It has been held that a prima facie case of obviousness exists where the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have the same properties. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 227 USPQ 773 (Fed. Cir. 1985). See MPEP 2144.05.
As to Claims 26 and 42, Wang does not specifically teach that the absorption step is pressurized. However, the claimed range of 100 kPa to 150 kPa overlaps ambient pressure. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the absorption step is performed at ambient pressure.
A prima facie case of obviousness exists where the claimed ranges and prior art ranges overlap or are close enough that one skilled in the art would have expected them to have the same properties. See MPEP 2144.05 I.”
As to Claim 30, Wang teaches that solid precipitates, that can include bicarbonate, are removed (page 42, left col, para. 3) and that the clear phase of the absorption solution is reused (section 2.2).
As to Claim 31, Wang teaches that solids form after CO2 absorption and that those solids include carbamate or bicarbonate (see pg 42, left col, para. 3). Furthermore, in their process, Wang teaches that the CO2-rich precipitates are heated to release the capture CO2 (section 2.2). The reference explains that specific precipitates heated include bicarbonate, which easily decomposes by heat (page 45, right col, lines 21-23). Although Wang does not specifically state that the by-product of the decomposition includes carbonate, since the compositions are the same and the process steps are the same, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that they would produce the same products.
As to Claim 32, Wang teaches that the desorption step is 393k (see section 2.2).
As to Claim 33, Wang teaches that 85% of the global energy is from fossil fuels, which are a source of CO2-containing gases (see Introduction, line 1). Therefore, although Wang does not specifically state that their process uses CO2 from combustion sources, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the CO2-derived gases used in Wang are from combustion since Wang explains that the majority of global energy is from these sources.
As to Claims 34 and 35, Wang describes use of amino acids, such as alanine (see section 2.1).
Liu describes use of an N-substituted form of amino acids (see title) and explains that when isopropyl is substituted at the alpha-amino group, it greatly enhanced the CO2 absorption capacity (see page 11307, left col, para. 1). Other useable amino acids include those in Table 1, which show an R group at the N and some show a R group at the C2 (for example, see PrNH-AlaNa). All the amino acids show an alkali metal associated with the O- (see table 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include the modified N-substituted amino acid, of Liu for use in the CO2 sequestering process using amino acids, as taught by Wang because Liu explains that these are useable and can be more effective than the use of amino acids alone.
Claim(s) 18, 28, 29 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang, KR ‘099, Park and Liu as applied to claim 15 above, and further in view of Pan (US Pub.: 2019/0183765).
Wang, KR ‘099, Park and Liu do not specifically teach that the process includes maintaining the pH at greater than 8.
Pan describes use of a salt of amino acids to form a carbamate (para. 8). Pan explains that it is known in the prior art that to synthesize bicarbonate with arginine by bubbling CO2 gas into a solution of amino acids (para. 8). In their process, Pan explains the inclusion of bases to form amino acid carbamate complexes (para. 10). The base can include NaOH, K2CO3 and others (para. 13). Pan explains that after CO2 is fed to the amino acid, carbamate complexes are formed when the pH is maintained above 8 (para. 70). However, as the pH drops due to the consumption of CO2, free bases in the solution become protonated and inhibits further formation of arginine carbamate (para. 70). Therefore, in order to move the reactor towards the formation of carbamate, Pan describe maintaining the pH of the solution above 8 (Para. 70) or can be 9.5 (para. 53).
Since Pan teaches that the pH is adjusted to a desired level, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the pH is monitored.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to maintain the pH at 8 or above, as taught by Pan for use with the absorption solution of Wang, KR ‘099, Park and Liu because use of this elevated pH, carbamate complexes are formed.
As to Claim 28, Wang does not specifically teach that the absorption step is pressurized. However, the claimed range of 100 kPa to 150 kPa overlaps ambient pressure. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the absorption step is performed at ambient pressure.
As to the pressure of the CO2 gas stream prior to adsorption, Rayner describes a system for capturing and releasing acid gases (title). The system feeds CO2 into a solvent that contains compounds that include amino acids as a means of capturing the CO2 gas (page 11, para. 3, 5). Rayner explains that when CO2 is absorbed into a solution at low pressure, CO2 update is lower, but when there is a higher pressure applied, CO2 update is increased (page 15, para. 1). Rayner explains that the pressure of the CO2 gas can range from 1-50 bar (page 11, para. 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention Wang, KR ‘099, Park and Liu to yield predictable results.
Claim(s) 36, 37 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang, KR ‘099, Park and Liu as applied to claim 34 above, and further in view of Zhao (CN 111185071) and evidenced by Sarcosine (Millipore Sigma).
Liu teaches that use of N-substituted amino acids are known to be effective, but the reference does not specifically teach use of the compound described in 36 and 37.
Zhao describes a CO2 sorption process that uses a basic amino acid salt to absorb the gas (abstract). Useable amino acid salts that can be used for this process includes: alanine, glycin, alanine salts, amino acid salts, serine salts (page 4, para. 7) but can also include other various, such as sodium sarcosine (page 4, para. 8).
Millipore Sigma shows that sarcosine is a name for N-methylglycine (see attached).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention employ sodium sarcosine, as taught by Zhao for use as the amino acid used in the absorption solution of CO2, Wang, KR ‘099, Park and Liu because Zhao explains that sodium sarcosine is a useable amino acid alternative to other amino acid absorbents, such as alanine salts, serine, lysine and arginine.
It would have been obvious to one skilled in the art to substitute sarcosine by its functional equivalent alanine, arginine, lysine in Wang with expected success. See MPEP 2144.06.
Claim(s) 38 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang, KR ‘099, Park and Liu as applied to claim 34 above, and further in view of (EP 2599536).
The references disclose use of an N-substituted amino acid, but not that the amino acid used is N-methyl alanine.
‘536 describes a method for treating an exhaust gas stream (title) that contains CO2 (para. 24) using an amino acid salt absorbent (para. 27). The amino acids salts useable as absorbents (para. 27) can include both non-sterically hindered or internally sterically hindered (para. 29). For the sterically hindered amino acids, ‘536 explains that suitable amino acids can include alkazyd M or N-methyl alanine (para. 30). Although ‘536 explains that non-sterically hindered amino acids are preferred for removing only CO2, the reference explains that sterically hindered amino acids, such as N-methyl alanine are useable (para. 30).
See MPEP, section: 2131.05 Nonanalogous or Disparaging Prior Art [R-08.2012]. "Arguments that the alleged anticipatory prior art is ‘nonanalogous art’ or ‘teaches away from the invention’ or is not recognized as solving the problem solved by the claimed invention, [are] not ‘germane’ to a rejection under section 102." Twin Disc, Inc. v. United States, 231 USPQ 417, 424 (Cl. Ct. 1986) (quoting In re Self, 671 F.2d 1344, 213 USPQ 1, 7 (CCPA 1982)). See also State Contracting & Eng’ g Corp. v. Condotte America, Inc., 346 F.3d 1057, 1068, 68 USPQ2d 1481, 1488 (Fed. Cir. 2003) (The question of whether a reference is analogous art is not relevant to whether that reference anticipates. A reference may be directed to an entirely different problem than the one addressed by the inventor, or may be from an entirely different field of endeavor than that of the claimed invention, yet the reference is still anticipatory if it explicitly or inherently discloses every limitation recited in the claims.).
A reference is no less anticipatory if, after disclosing the invention, the reference then disparages it. The question whether a reference "teaches away" from the invention is inapplicable to an anticipation analysis. Celeritas Technologies Ltd. v. Rockwell International Corp., 150 F.3d 1354, 1361, 47 USPQ2d 1516, 1522-23 (Fed. Cir. 1998) (The prior art was held to anticipate the claims even though it taught away from the claimed invention. "The fact that a modem with a single carrier data signal is shown to be less than optimal does not vitiate the fact that it is disclosed.").
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a N-methyl alanine amino acid in the adsorption solution, as taught by ‘536 for use with the CO2 absorption solution of Wang, KR ‘099, Park and Liu because ‘536 explains that this amino acid has predictable results for CO2 sorption.
Claim(s) 39 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang, KR ‘099, Park and Liu as applied to claim 35 above, and further in view of Ingram (CN108367232).
The references teach N-substituted amino acids, but does not teach the compound of Claim 39.
Ingram describes a gas absorption system (abstract) that can include a CO2 absorbent useable with other pollutants (page 4, para. 3). The absorbent used can include amino acids (page 9, para. 3), one of which can include N-methyl serine (page 4, para. 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use N-methyl serine, as taught by Ingram for use with the amino acids of Wang, KR ‘099, Park and Liu because these are known to predictably absorb CO2.
Claim(s) 40 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang, KR ‘099, Park and Liu as applied to claim 15 above, and further in view of Voyer (CN 106999842).
Wang, KR ‘099, Park and Liu describes K2CO3, but does not teach use of varying levels of carbonation.
Voyer describes a CO2 capature system that employs amino acids (page 5, para. 7) as an absorber (page 3, lines 18-19). The system incorporates a carbonate and a adjusts the pH to be basic (page 3, lines 22-28). To generate a bicarbonate product (page 3, line 25). Voyer explains that the carbonate source used can be potassium carbonate whose concentration can vary from 2M to 1M (page 4, lines 12-14). In some embodiments, it can vary between 2M to 1M to a value of 1.25M or 1.75M (page 4, lines 13-15).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to vary the K2CO3 concentration, as taught by Voyer for use with Wang, KR ‘099, Park and Liu to yield predictable results in sequestering CO2.
Claim(s) 43, 44 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang “Phase Change amino acid salt separates into CO2-rich and CO2-lean phases upon interacting with CO2”, and in view of KR102069099 and in view of Park “Screening test for aqueous solvents used in CO2 capture. . “, and in view of Liu “Equimolar CO2 Capture by N-substituted Amino Acid Salts and Subsequent Conversion” and in view of Zhang (CN 103221114).
Wang describes a CO2 capture process (see introduction, para. 2-3), which uses a CO2 absorption solution to sequester the gas (Introduction, para. 3). Wang explains that “amino acids are of great interest. . . for CO2 capture” (Introduction, para. 4). Therefore, in their process, Wang combines an amino acid (see section 2.1, which uses alanine, arginine, lsine and serine, which are all amino acids) with NaOH in water (deuterium oxide is water) (section 2.1, para. 1). This solution is used to absorb CO2 (see section 2.2). In some embodiments, Wang teaches that in the prior art, citing to Hook, that the amino absorption solution that can be used here can be an N-methyl-substituted 2-aminoethanol (page 45, line 36), but Wang does not specifically teach that the N-substituted amino compound is an amino acid.
As to the alkali salt feature, Wang shows in their NMR analysis that the alanaine contains Na (Fig. 2). This can be considered an inorganic alkali salt of the amino acid.
CO2 absorption is performed in a reactor (see section 2.2), which can be considered an absorber vessel. A precipitate was produced between the amino acid and the CO2 (section 2.2). As to the reaction mechanism, Wang analyzes the reaction and describes the reaction process as follows: the alanine solution reacted with CO2 to form Ala carbamate (-OOCCHCH3NHCOO-) (see section 3, para. 2, lines 5-6).
In Claim 15, lines 7-8, the claims describe that the CO2 reacts with the amino acid and then “adds a carbonate group to the amino group”, which should be COOO, but table 1 of the current specification shows that in step 1, CO2- is added to the amino acid group by adding a COO- group (see table 1 of the specification). Therefore, the carbonate group of Claim 15 will be treated as a COO- group.
Similarly, in the mechanism of Wang, after CO2 and alanine react, a COO- group is added to the compound (see page 43, right col, formula in last para).
As mentioned above, the process of absorption takes place in the presence of NaOH (see section 2.1). Therefore, the reaction conditions are considered alkaline.
The first reaction is:
CO2 + 2-OOCCHCH3NH2- = -OOCCHCH3NHCOO- + -OOCCHCH3NH3+ (see page 43).
In the equation above, the second compound loses a hydrogen from “-NH2-“ to make “-NH-“, which can be considered a deprotonating-step of the carbamate group as described by Claim 15.
Wang explains that the first reaction has low stability (see page 43, last line) and therefore, the reaction proceeds to the reaction shown on page 45, which shows:
-OOCCHCH3NHCOO- + H2O = -OOCCHCH3NH2 + HCO3- (see equate on page 45).
This can be considered a hydrolysis step of the carbamate group, which produces a bicarbonate and regenerates the amino acid.
As to the amino acid being a catalyst, since the amino acid used goes back to the same composition after the reaction, after it is used to facilitate the reaction, then it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that this can be considered a catalyst.
As to the bicarbonate being an alkali precipitate, Wang teaches that the precipitate can include bicarbonate (page 43, right col, lines 16-17 and line 3-5, where NaHCO3 is in the milky phase, but less so in the clear phase). As t the bicarbonate being an alkali, Wang teaches formation of NaHCO3 (page 43, right col, lines 6-7).
Wang does not teach that the base used is a potassium carbonate used in a concentration range of 30-60wt% in an aqueous solvent.
As to the use of potassium carbonate, KR ‘099 teaches an absorbent used for separating CO2 from a gas mixture (title). The absorbent mixture is combined with a second compound, which can be NaOH, KOH, K2CO3, Na2CO3 or NaHCO3 (page 3, “step (a), para. 4”). The absorbent can include amino acids, such as alanine, serine, arginine (page 3, last para).
It would have been obvious to one skilled in the art to substitute the NaOH of Wang
by its functional equivalent potassium carbonate, as taught by KR “099 with expected success. See MPEP 2144.06.
As to the concentration of potassium carbonate in water, Park describes use of an aqueous solvent for use in CO2 capture (title). Pak explains that when combining K2CO3 with amino acid salts, the absorptivity rate may increase (see Introduction, col. 2, lines 5-6). As to the amount, Park explains that in experimental tests, a concentration of 30wt% K2CO3 in water was effective (see section 1, para. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ K2CO3 in an amount of 30 wt%, as taught by Park for use with the K2CO3 of KR ‘099 in the absorption solution of Wang because this amount of K2CO3 would lead to predictable CO2 sequestration results.
As to the amino acid being N-substituted, the references do not specifically describe this.
Liu describes CO2 Capture (title). The reference explains in the background that conventional technology for the industrial capture of CO2 is known to employ amines (page 11306, left col, para. 2). Some of these amines include various amino acids (see Table 1). CO2 sequestration is known to form carbamate salts (pg 11306, right col, last para). As to the use of an N-substituted amino acid, Liu explains that to their “delight, introducing isopropyl substituent at the alpha-amino group greatly enhanced the CO2 capacity” (page 11307, left col, para. 1). Liu explains that various substitutions vary the CO2 absorption (see table 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a N-substituted amino acid, as taught by Liu for use with the CO2 absorption solution of Wang, KR ‘099 and Park because Liu explains that use of a N-substituted amino acids are known to greatly enhance the CO2 capacity of the adsorption solution.
As to separating the potassium bicarbonate precipitate, recycling the solvent and converting the bicarbonate to potassium arbonate using a heat source and forming a gas stream rich in CO2, Wang states that in tests, to explore the CO2 desorption performance, the bicarbonate was heated to decompose the product, which lead to the formation of carbmate and CO2 (see page 45, right col. para. 2), but the references do not teach all the features of steps (iv) and (v) of the claim.
Zhang describes a method for capture CO2 and other pollutants in exhaust gas stream (title) using ab amino-based adsorption solution (abstract). The solution can include an amino acid (para. 32). The system absorbs CO2 and then forms potassium bicarbonate precipitates, which are separated (para. 20, 32). The bicarbonate is converted to carbonate (para. 32). Potassium carbonate is then decomposed and CO2 is released (para. 32). The rest of the solvent is recycled for reuse (para. 82). The decomposition occurs using heat (para. 149).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to remove the precipitate, convert it to potassium carbonate, decompose it to release CO2 and recycle the solvent, as taught by Zhang for use with the process of Wang, KR ‘099, Park and Liu because reuse of the solvent is a known and effective means of reusing the absorber and heating the precipitate would lead to predictable and expected results by one of ordinary skill in the art.
Conclusion
THIS ACTION IS MADE FINAL. 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.
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/SHENG H DAVIS/Primary Examiner, Art Unit 1732 May 5, 2026
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