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 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.
Claim(s) 1, 3-6, and 9-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shishkov (US 2013/0231493 A1), in view of Wifong (US 10,065,174 B1).
With respect to claim 1, Shishkov and Wifong teach the claimed amino compound-supported porous substrate.
Claim 1 requires "[a]n amino compound-supported porous substrate comprising." Shishkov teaches porous inorganic bodies used as carriers and having high accessibility and large transport pores (Shishkov,, [0050]-[0052]). Wifong teaches sorbents in which amines are deposited onto porous supports for carbon dioxide capture (Wifong, col. 2, line 17-29). The combined teachings therefore correspond to an amino compound-supported porous substrate.
Claim 1 further requires "a porous substrate including at least macropores." Shishkov teaches a porous inorganic body having mercury-measured pores from 0.005 to 1000 micrometers, including pores greater than 20 micrometers (Shishkov, [0033], [0039]-[0042]). Shishkov Example 2 teaches mercury-intrusion pore volume throughout this range and main maxima at 400, 10, 6, and 0.4 micrometers (Shishkov, [0249]-[0250]).
Claim 1 further requires "an amino compound supported in at least some pores of the porous substrate." Shishkov does not teach "an amino compound supported in at least some pores of the porous substrate." However, Wifong teaches porous silica supports containing primary, secondary, and tertiary amines deposited in the support pores and teaches Class 1 sorbents made by wet impregnation of silica with PEI, TEPA, or other polyamines (Wifong, col. 2, line 20-29; col 3, lines 1-17 ). Wifong also teaches mixing already-fabricated porous pellets with an impregnation solution containing TEPA or PEI so that the amine is supported within the pellet pores (Wifong, col. 2, line 20-29; col 3, lines 1-17).
Claim 1 further requires "wherein the porous substrate has a total pore volume per unit volume of the porous substrate of 0.55 mL/mL or more and 0.95 mL/mL or less, as determined by mercury porosimetry." Shishkov does not explicitly teach "a total pore volume per unit volume of the porous substrate of 0.55 mL/mL or more and 0.95 mL/mL or less, as determined by mercury porosimetry." Shishkov instead reports the mercury-intrusion value per unit mass. Specifically, Shishkov Example 2 reports a total pore volume of 0.988 mL/g for pores from 0.005 to 1000 micrometers (Shishkov, [0249]). Shishkov identifies the ceramic powder as alumina (Shishkov, [0241]). The National Institute of Standards and Technology teaches an aluminum-oxide density of 3.970 g/cm3 in "Composition of Aluminum Oxide." One gram of alumina therefore occupies approximately 0.252 mL, and one gram of Shishkov’s porous body has an approximate external volume of 1.240 mL (0.988 mL pore volume + 0.252 mL solid volume). Shishkov’s pore volume per unit substrate volume is therefore approximately 0.797 mL/mL (0.988/1.240), which falls within the claimed range. This calculation is consistent with the present application’s instruction to multiply pore volume per unit mass by bulk density to obtain pore volume per unit volume.
It would have been obvious to a person having ordinary skill in the art before the effective filing date to impregnate Shishkov’s high-pore-volume inorganic substrate with Wifong’s amino compound. Shishkov teaches that large transport pores facilitate reagent transport and access during diffusion-limited reactions (Shishkov, [0003]). Wifong teaches that carbon dioxide diffuses through the pellet and its pores before reacting with the immobilized amine groups and expressly impregnates previously fabricated porous pellets with PEI or TEPA (Wifong, col. 5, lines 20-39; col 14, lines 20-39). A person having ordinary skill in the art therefore would have had reason to use Shishkov’s accessible porous carrier as Wifong’s amine support to facilitate gas access to the immobilized amine, with a reasonable expectation of obtaining a solid carbon-dioxide sorbent in which the amine is supported in the carrier pores.
Regarding claim 3, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 3 further requires "wherein the porous substrate has a skeleton containing an element selected from the group consisting of silicon, aluminum, tin, cerium, titanium, and zirconium." Shishkov teaches that the porous body preferably contains alumina and more preferably contains at least 99 wt.% alpha-alumina (Shishkov, [0046]-[0047]). Shishkov Example 2 teaches use of alumina as the ceramic powder (Shishkov, [0241]).
Regarding claim 4, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 4 further requires "wherein the amino compound-supported porous substrate includes an amino group in an amount, per unit volume of the amino compound-supported porous substrate, of 1.0 mmol/mL or more and 30.0 mmol/mL or less." Shishkov and Wifong do not explicitly teach "an amino group in an amount, per unit volume of the amino compound-supported porous substrate, of 1.0 mmol/mL or more and 30.0 mmol/mL or less." However, Wifong teaches PEI and other polyamines containing primary, secondary, and tertiary amino groups and teaches amine loadings of 1-65 wt.%, preferably 20-45 wt.% (Wifong, col. 6, line 44-67). A 20 wt.% PEI loading in the final sorbent corresponds to 0.25 g PEI per gram of Shishkov’s support. The PEI repeat unit has a molar mass of approximately 43.07 g/mol and includes one amino nitrogen. The disclosed loading therefore supplies approximately 5.8 mmol amino groups per gram of support. Using Shishkov’s calculated external support volume of approximately 1.240 mL/g gives approximately 4.7 mmol amino groups per mL, within the claimed range.
Wifong teaches the amount of immobilized amine as affecting carbon-dioxide capacity and diffusion and deliberately varies amine loading over a broad range (Wifong, col. 6, line 44-67). It would have been obvious to select a Wifong amine loading that provides an amino-group concentration within the claimed range to provide reactive amine sites while maintaining pore diffusion. The expected result would have been an amino-functional sorbent having sufficient amine sites for carbon-dioxide capture without filling the pore network to the point that gas transport is prevented.
Regarding claim 5, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 5 further requires "wherein the amino compound is at least one selected from the group consisting of a polyamine, a primary amine, a secondary amine, a tertiary amine, a quaternary ammonium, an aromatic amine, and a polyimine." Wifong teaches polyamines containing combinations of primary, secondary, and tertiary amino groups, including polyethylenimine, ethylenimine oligomers, tetraethylenepentamine, pentaethylenehexamine, and hexaethyleneheptamine (Wifong col 6, line 44-67). Wifong’s polyethylenimine and tetraethylenepentamine are polyamines and therefore satisfy at least one of the alternatives recited in claim 5.
Regarding claim 6, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 6 further requires "wherein the amino compound-supported porous substrate has a total pore volume, per unit volume of the amino compound-supported porous substrate, of 0.05 mL/mL or more and 0.80 mL/mL or less, as determined by mercury porosimetry." Shishkov and Wifong do not explicitly teach "a total pore volume, per unit volume of the amino compound-supported porous substrate, of 0.05 mL/mL or more and 0.80 mL/mL or less, as determined by mercury porosimetry." Shishkov’s unfilled porous substrate has a calculated total pore volume of approximately 0.797 mL/mL. Wifong teaches impregnating porous supports with variable amine amounts from 1-65 wt.% and teaches amine-to-silica weight ratios from 1:3 to 1:1 (Wifong, col. 6, lines 44-67; col 14, lines 20-69). Supporting amine in Shishkov’s pores would reduce the mercury-accessible pore volume from the approximately 0.797 mL/mL starting value. Wifong also teaches that carbon dioxide must diffuse through the pellet and support pores to reach the amine and uses a pore former to preserve porosity (Wifong, col. 5, lines 44-67; col 14, lines 20-39). Wifong therefore recognizes amine loading and retained porosity as variables affecting sorption and gas transport.
It would have been obvious to select a lower or intermediate amount from Wifong’s disclosed amine-loading range so that Shishkov’s initially open pore network remained partially unfilled. Such selection would predictably reduce the starting pore volume below 0.797 mL/mL while retaining substantially more than 0.05 mL/mL for the pore diffusion Wifong requires.
Regarding claim 9, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 9 further requires "wherein the porous substrate is a molded article." Shishkov teaches porous inorganic bodies formed by extrusion and identifies strands, rings, balls, and cylinders as suitable body geometries (Shishkov, [0050]). Shishkov Example 2 extrudes the alumina mixture through an 8 x 3 mm ring nozzle and calcines the resulting body (Shishkov, [0240]-[0249]).
Regarding claim 10, modified Shishkov teaches the subject matter of claim 9 as discussed above.
Claim 10 further requires "wherein the molded article is a columnar body and has an average diameter of 1.5 mm or more and 20 mm or less." Shishkov expressly teaches cylindrical porous bodies having an outer diameter from 2 to 20 mm (Shishkov, [0050]). A cylinder is a columnar body, and Shishkov’s 2-20 mm diameter range overlaps and is contained within the claimed 1.5-20 mm range.
Regarding claim 11, modified Shishkov teaches the subject matter of claim 9 as discussed above.
Claim 11 further requires "wherein the amino compound-supported porous substrate has a compression strength of 5 N or more." Modified Shishkov does not expressly teach "wherein the amino compound-supported porous substrate has a compression strength of 5 N or more." However, Wifong teaches amino-containing cylindrical sorbent pellets having a diameter of approximately 1.7 mm and a length of approximately 5 mm (Wifong, col.16, lines 53-55). Wifong defines crush pressure as crush force divided by pellet diameter times pellet length (Wifong, col 13, lines 60-70). Wifong reports a crush pressure of 1.57 MPa for pellet P4 (Wifong, col 17, lines 7-32 and table 3). Using Wifong’s disclosed formula and dimensions, the corresponding crush force is approximately 13.35 N: 1.57 N/mm2 x 1.7 mm x 5 mm. This calculated force exceeds the claimed 5 N.
It would have been obvious to provide the modified Shishkov sorbent with Wifong’s strength additive, polymer binder, and pellet-forming conditions because Wifong teaches that these constituents provide structural integrity and increased crush strength for gas-separation service (Wifong, col. 5, lines 10-20).
With respect to claim 12, modified Shishkov teaches the amino compound-supported porous substrate of claim 1 as discussed above. Claim 12 requires "[a]n acid gas adsorbent material comprising the amino compound-supported porous substrate according to claim 1." Shishkov does not teach "[a]n acid gas adsorbent material comprising the amino compound-supported porous substrate according to claim 1." However, Wifong teaches a solid supported-amine sorbent that removes carbon dioxide from gaseous mixtures by diffusion into the porous pellet followed by reaction with immobilized amine groups (Wifong, col. 5, lines 1-20). Carbon dioxide is an acidic gas. Wifong’s carbon-dioxide sorbent therefore corresponds to an acid gas adsorbent material comprising the amino compound-supported porous substrate produced by the combination. The reason for using Shishkov’s porous body as Wifong’s supported-amine carbon-dioxide sorbent is the same pore-access and diffusion rationale stated for claim 1.
Claims 2, 7, and 8 are rejected under 35 U.S.C. § 103 as being unpatentable over Shishkov (US 2013/0231493 A1) in view of Wifong (US 10,065,174 B1), as applied to claim 1 above, and further in view of Miyamoto (WO 2017/002871 A1) (See translated doc).
Regarding claim 2, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 2 further requires "wherein the porous substrate has a mode of pore size distribution of the macropores of 0.05 μm or more and 3.0 μm or less, as determined in a pore size range of 50 nm or more and 500 μm or less by mercury porosimetry." Shishkov and Wifong do not clearly teach "a mode of pore size distribution of the macropores of 0.05 μm or more and 3.0 μm or less, as determined in a pore size range of 50 nm or more and 500 μm or less by mercury porosimetry." Shishkov reports several local maxima, including 0.4 micrometer, but does not establish that the 0.4-micrometer peak is the mode over the claimed macropore analysis range (Shishkov, [0250]). However, Miyamoto teaches a silica porous body having through-holes and smaller pores and defines their mode diameters as mode values measured by mercury intrusion (Miyamoto, [0020]). Miyamoto reports a through-hole, i.e., macropore, mode of approximately 1.77 micrometers (Miyamoto, [0020], Fig. 2). The 1.77-micrometers falls within the claimed 0.05-3.0 micrometer range and within the claimed 50 nm-500 micrometer analysis window.
It would have been obvious to use Miyamoto’s disclosed macropore mode in the porous support of modified Shishkov. Miyamoto teaches a hierarchical pore system in which the continuous network and through-holes permit a reaction target to diffuse into and contact the porous body (Miyamoto, [006]). Wifong likewise teaches that carbon dioxide must diffuse through the support pores to reach the immobilized amines (Wifong, col. 5, lines 10-20) Selecting Miyamoto’s disclosed macropore distribution would therefore predictably facilitate gas transport to the supported amine sites.
Regarding claim 7, modified Shishkov teaches the subject matter of claim 1 as discussed above.
Claim 7 further requires "wherein the porous substrate further includes mesopores, and the porous substrate has a co-continuous structure composed of: a skeleton including the mesopores formed therein; and the macropores." Shishkov and Wifong do not explicitly teach "the porous substrate has a co-continuous structure composed of: a skeleton including the mesopores formed therein; and the macropores." However, Miyamoto teaches a silica porous body having a three-dimensional continuous-network skeleton, through-holes formed between portions of the skeleton, and smaller pores formed from the skeleton surface into the skeleton interior (Miyamoto, [0035]-[0036]). Miyamoto reports the smaller pore mode as approximately 17 nm, which is within the mesopore range, and the through-hole mode as approximately 1.77 micrometers, which is within the macropore range (Miyamoto, [0037], Fig. 2). Miyamoto further teaches spinodal decomposition that forms a co-continuous silica-hydrogel phase and solvent phase, producing the three-dimensional continuous network and through-hole architecture (Miyamoto, [0044]). Miyamoto’s skeleton pores and intervening through-holes therefore correspond to the claimed skeleton including mesopores and the macropores of the co-continuous structure.
It would have been obvious to employ Miyamoto’s known co-continuous hierarchical pore architecture in modified Shishkov because Miyamoto teaches that the structure permits diffusion and contact within the porous body (Miyamoto, [0002], [0035]-[0037]), and Wifong teaches that carbon dioxide must diffuse through the support pores to reach the amine groups (Wifong, col. 5, lines 10-20). The expected result would have been improved gas access to the immobilized amine sites through connected macro- and mesopore pathways.
Regarding claim 8, modified Shishkov teaches the subject matter of claim 7 as discussed above.
Claim 8 further requires "wherein the porous substrate has a ratio of a mode of pore size distribution of the macropores to a mode of pore size distribution of the mesopores of 5 or more and 200 or less." Miyamoto teaches a macropore or through-hole mode of approximately 1.77 micrometers and a mesopore mode of approximately 17 nm (0.017 micrometers), both obtained from the disclosed pore-size distribution (Miyamoto, [0020], Fig. 2). Converting 17 nm to 0.017 micrometer gives a macropore-to-mesopore mode ratio of approximately 104 (1.77/0.017), which falls within the claimed range of 5-200. Miyamoto also teaches generally that the through-hole mode is at least five times the smaller-pore mode (Miyamoto, [0020]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to STARFARI TESHAWN MCCLAIN whose telephone number is (571)272-0169. The examiner can normally be reached M-F 8 AM- 5 PM.
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/STARFARI TESHAWN MCCLAIN/Examiner, Art Unit 1736
/DANIEL C. MCCRACKEN/Primary Examiner, Art Unit 1736
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