DETAILED ACTION
Claim(s) 1-19 were rejected in Office Action mailed on 11/18/2025.
Applicant filed a response, amended claim(s) 1-19, on 02/18/2026.
Claim(s) 1-24 are pending, and claim(s) 20-24 are withdrawn.
Claim(s) 1-19 are rejected.
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
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 1-19 are rejected under 35 U.S.C. 103 as being unpatentable over Tian et al., Calcium-looping reforming of methane realizes in situ CO2 utilization with improved energy efficiency, Sci. Adv., 2019 (Tian) (provided in IDS received on 08/25/2025), in view of Tan et al., Application of microwave heating for methane dry reforming catalyzed by activated carbon, Chemical Engineering & Processing: Process Intensification, 2019 (Tan).
Regarding claims 1-2, 5, 7-9 and 14, Tian teaches calcium-looping reforming of methane, which couples the calcium-looping CO2 capture and the CH4 dry reforming reactions in the CaO-Ni bi-functional sorbent-catalyst (reading upon a solid catalyst, Ni reads upon at least one metal species), where the CO2 captured by CaO is reduced in situ by CH4 to CO (Tian, Abstract);
the methane dry reforming reaction is:
CH4 (g)+CO2 (g)[Wingdings font/0xE0]2CO (g)+2H2 (g) (Tian, page 1, formula 1), reading upon a process for producing a gaseous product comprising hydrogen, and CH4 reads upon a gaseous hydrocarbon.
Tian further teaches in the CO2 capture step, CaO in the material separates CO2 from the gas streams and stores CO2 in the form of CaCO3 (CaCO3 reads upon a support, wherein the support comprises at least one of a carbonate or an alkaline earth metal oxide) (Tian, page 2, left column, 2nd paragraph).
Further regarding claim 1, Tian does not explicitly disclose the CH4 dry reforming reaction comprises exposing to microwave radiation.
With respect to the difference, Tan teaches catalyzed methane dry reforming (Tan, Title, Abstract). Tan specifically teaches application of microwave heating for methane dry reforming (Tan, Title, Abstract).
As Tan expressly teaches, methane dry reforming is a strong endothermic reaction and an efficient heating method is needed; microwave heating in catalytic reactions, such as gas-solid, had displayed an improved performance as compared to conventional heating. In some works, it had been testified microwave-assisted processes had lower energy consumption, along with higher heating rates and the desirable production distribution (Tan, page 2, left column, 2nd paragraph).
Tan is analogous art as Tan is drawn to catalyzed methane dry reforming.
In light of the motivation of using microwave heating in catalytic reaction, such as methane dry reforming, as taught by Tan, it therefore would have been obvious to a person of ordinary skill in the art to use microwave heating (i.e., microwave radiation) in the in situ reform of CH4 of Tian, which would necessarily include exposing methane to microwave in the presence of the bi-functional sorbent-catalyst, in order to achieve an improved performance, lower energy consumption, along with higher heating rates and desirable production distribution, and thereby arrive at the claimed invention.
Regarding claims 3-4, as applied to claim 1, given that Tian in view of Tan teaches the methane dry reforming reaction is:
CH4 (g)+CO2 (g)[Wingdings font/0xE0]2CO (g)+2H2 (g) (Tian, page 1, formula 1), the gasesous products are CO and H2 and in a molar ratio of 1:1, i.e., the gaseous product comprises 100 vol.% H2 and CO in the total amount of the gaseous product.
Regarding claim 6, as applied to claim 1, Tian in view of Tan further teaches in some cases, the material (i.e., as-synthesized sorbent-catalyst CaO-Ni) was fully reduced by H2 before use (Tian, page 7, left column, 2nd paragraph), i..e, the fully reduced material has elemental nickel.
Regarding claims 10-11, as applied to claim 1, Tian in view of Tan further teaches freshly calcined sorbent catalyst with different Ca-to-Ni molar ratio shown in Fig. 2, such as CaO/Ni_19, which has a Ca-to-Ni molar ratio of 1:19 (Tian, page 3, right column, Fig. 2), which reads upon the claimed ranges.
Alternatively, regarding claim 11, as applied to claim 1, Tian in view of Tan further teaches freshly calcined sorbent catalyst with different Ca-to-Ni molar ratio shown in Fig. 2, including CaO/Ni_4, CaO/Ni_9, CaO/Ni_19, which has a Ca-to Ni molar ratio of 1:4, 1:9 and 1:19 (Tian, page 3, right column, Fig. 2), it therefore would have been obvious to a person of ordinary skill in the art to use an molar ratio within the range of the three molar ratios, including a molar ratio of Ca-to-Ni of 18, and achieve desired catalyst performance requirement.
Regarding claim 12, as applied to claim 1, Tian in view of Tan teaches in the CO2 capture step, CaO in the material separates CO2 from the gas streams and stores CO2 in the form of CaCO3 (Tian, page 2, left column, 2nd paragraph). It therefore would have been obvious to a person of ordinary skill in the art to achieve complete conversion of CaO into CaCO3, to maximize CO2 capture, and therefore there is only calcium carbonate in additional the nickel species.
Tian in view of Tan further teaches in some cases, the material (i.e., as-synthesized sorbent-catalyst CaO-Ni) was fully reduced by H2 before use (Tian, page 7, left column, 2nd paragraph), i.e., the fully reduced material has elemental nickel.
Regarding claim 13, as applied to claim 1, the claims further limit the alkaline earth metal oxide is calcium oxide which is an optional embodiment of claim 1 and therefore not required. As such, claim 13 is are rejected based on identical/substantially identical reasons as claim 1.
Regarding claim 15, as applied to claim 1, Tian in view of Tan further teaches in Process tests, CH4 flow (i.e., 100 vol.% methane) was used for CH4 reforming (Tian, paragraph spanning between pages 7-8).
Regarding claims 16-18, as applied to claim 1, Tian in view of Tan further teaches subsequently, a new calcium looping CH4 reforming cycle was started by the introduction of a CO2 flow (Tian, paragraph spanning between pages 7-8), reading upon treating a spent catalyst with a source of carbon dioxide, wherein the source of carbon dioxide is a source of gaseous carbon dioxide, and the spent catalyst after the treatment with the source of carbon dioxide is uses as the solid catalyst.
Regarding claim 19, as applied to claim 1, Tian in view of Tan further teaches introducing a CH4 flow to calcine the sample, subsequently the temperature was decreased, and then a new calcium looping CH4 reforming cycle was started by the introduction of a CO2 flow (Tian, paragraph spanning between pages 7-8), reading upon wherein the spent catalyst is calcined prior to treatment with a carbon dioxide source.
Response to Arguments
Applicant primarily argues:
“As acknowledged by Tian et al., the process therein involves both CaCO3 calcination and CH4 dry reforming which are highly endothermic reactions which require high energy input to drive them (see Tian et al., page 1, RH column). Consequently, the process of Tian et al. employs high temperature thermal heating, firstly in the uptake of carbon dioxide by the sorbent (873K, ~600°C) and secondly in heating both the bifunctional catalyst in the presence of methane to 1073K (~800°C) in order to release CO2 and reform the methane (see Tian et al., paragraph bridging page 7 and 8).
However, as highlighted in the application as filed (see paragraph 7) the CO2 uptake capacity of the calcium sorbent normally decreases very quickly after several cycles in these high temperature processes. This problem is demonstrated in Kim et al. (cited in the Information Disclosure Statement of Nov. 2, 2022) where, at page 2818, LH column, penultimate paragraph, it is disclosed that in a typical experiment 1.Og of precalcined limestone was mixed with 1.0 g of Ni/MgO-A12O3 catalyst and heated to 800°C. Subsequently the temperature was reduced to 720°C for the carbonation reaction. Kim et al. describes, at page 2819 (paragraph bridging columns 1 and 2) that regeneration of the CO2 sorbent is a transient process due to depletion of the CO2 sorbent with time. This paragraph explains that after 42 minutes the quantity of CO2 released decreases (see figure 2f). HR-SEM micrographs of the fresh and cycled limestone revealed appreciable sintering (see page 2820, last paragraph, LH column, figure S7a) reducing pore volume and thus reducing the CO2 uptake capacity. Kim et al. reports that the irreversible decay of the CO2 sorbent leads to a loss of ~50% of its uptake capacity within 5 cycles (see page 2820, first paragraph).
Consequently, Kim et al. suggests modification of the sorbent by the incorporation of high Tamman temperature stabilizers (such as A12O3, ZrO3 or MgO) may be considered (see p.2820, RH column first paragraph) or a continuous supply of fresh CaO sorbent (see p.2820, RH column, second paragraph). However, Kim et al. does not teach or suggest using microwave radiation in the process therein or the effects thereof.
Similar to Kim et al., Tian et al. recognizes this problem at page 5, RH column, second paragraph which states "conventional CaL has to be operated at elevated temperatures above 1173 K. However, this comes at the cost of a decay in the CO2 capture capacity of all CaO-based sorbents due to high-temperature sintering, which is the most serious problem restricting the development of such a process for CO2 capture." Furthermore, supplemental figure 5 of Tian et al. (enclosed herewith) demonstrates a decline in the CO2 capture of the prepared sorbent-catalysts in the CaL methane reforming process disclosed therein across a number of cycles.
The presently claimed process avoids the high temperatures of both Tian et al. and Kim et al. which lead to sintering of the CO2 sorbent. The presently claimed method using microwave radiation allows rapid and selective heating offering the potential of calcination of the sorbent and reforming hydrocarbon at relatively low catalyst bed temperatures thus minimizing the CO2 uptake capacity losses of CO2 sorbent (see paragraphs [0009] and [0010] of the application as filed).”
Remarks, p. 7-8
The Examiner respectfully traverses as follows:
It is noted, “Mere recognition of latent properties in the prior art does not render nonobvious an otherwise known invention. In re Wiseman, 596 F.2d 1019, 201 USPQ 658 (CCPA 1979).” See MPEP 2145 II. Further, the fact that applicant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Given the calcium-looping reforming of methane with microwave radiation in Tian in view Tan is substantially identical to the process used in the present invention, as set forth on pages 6-8, it is clear that the calcium-looping reforming of methane with microwave radiation in Tian in view Tan would intrinsically have the substantially identical advantages as the present invention.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 (I).
Applicant further argues:
“Thus the claimed process provides a method of producing syngas from a gaseous hydrocarbon (such methane) wherein an effective reforming reaction can be achieved at catalyst bed temperature below 200°C leading to stable and consistent CaCO3 conversion and methane reforming for at least 12 cycles (see Figure 6). Furthermore, Figure 8D of the present application shows that the bifunctional catalyst after 12 cycles of CO2 capture and methane reforming has a CaO sorbent still possessing porous nano structures facilitating CO2 capture.
This would not have been predictable based on the cited art.”
“Furthermore, it would not have been predictable that by doing so the known issue of CO2 uptake capacity losses with respect to the sorbent would be ameliorated as the teachings of Tan et al. have no relevance sorbent capacity.”
Remarks, p. 8-9
The Examiner respectfully traverses as follows:
The data to show advantageous effects by the process for producing a gaseous product comprising hydrogen, in the present invention is not persuasive for the following reasons.
Firstly, the data is not commensurate in scope with the scope of the claims. The specification only provides data for a process for producing a specific gaseous product comprising hydrogen, said process comprising exposing specific hydrocarbon to microwave radiation for specific intensity and specific duration of time in the presence of a specific solid catalyst, wherein the solid catalyst comprises a specific metal with a specific amount on a specific support; whereas the present claim broadly recites a process for producing any gaseous product comprising hydrogen, said process comprising exposing any gaseous hydrocarbon to microwave radiation of any intensity for any duration of time, in the presence of any solid catalyst, wherein the solid catalyst comprises at least one metal species on a support, wherein the metal species is at least one of a nickel species or a cobalt species, and wherein the support comprises at least one of a carbonate or an alkaline earth metal oxide.
Secondly, the data does not provide proper side-by-side comparison.
Applicant further argues:
“The Examiner refers to Tan et al. and considers that a person of skill in the art would be motivated to use microwave heating in the process of Tian et al. simply because Tan et al. discloses its applicability to methane dry reforming. However, as highlighted above, there is a second key process in Tian et al. having a substantial energy requirement, i.e. the calcination of the CO2 sorbent in order to supply the CO2 feed for the MDR reaction. Tan et al. whilst disclosing a microwave assisted method of carbon dioxide reforming of methane, does not provide any teachings relevant to CO2 capture and subsequent decomposition of a sorbent under the process conditions to provide a source of CO2 for the reaction, let alone specifically calcium looping. Instead, Tan et al. employs a feed gas stream comprising carbon dioxide (see page 5, section entitled "Effect of CH4/CO2 ratio in the feed gas"; also Figure 1 which shows the various feed gases).
Accordingly, Tan et al. provides no teaching which would provide a person skilled in the art with a reasonable expectation that the microwave method therein would be useful in the calcium looping mediated process of Tian et al.”
Remarks, p. 9
The Examiner respectfully traverses as follows:
Firstly, the present claim does not require CO2 capture and subsequent decomposition of a sorbent under the process conditions to provide a source of CO2 for the reaction. Therefore, the fact remains that Tian in view of Tan meet the present claims, absent evidence to the contrary.
Secondly, Tian and Tan are both drawn to catalyzed methane dry reforming, and Tan provides proper motivation to combine, namely methane dry reforming is a strong endothermic reaction and an efficient heating method is needed; microwave heating in catalytic reactions, such as gas-solid, had displayed an improved performance as compared to conventional heating. In some works, it had been testified microwave-assisted processes had lower energy consumption, along with higher heating rates and the desirable production distribution (Tan, page 2, left column, 2nd paragraph). See page 7 set forth above. Therefore, it is the Examiner’s position that there would be a reasonable expectation of success by combining Tian and Tan.
Further, it is noted that it is well settled that obviousness does not require absolute predictability of success; all that is required is a reasonable expectation of success. In re Kubin, 561 F.3d 1351, 1360 (Fed. Cir. 2009); In re O’Farrell, 853 F.2d 894, 903-04 (Fed. Cir. 1988). See MPEP 2143E.
Therefore, the Examiner has fully considered Applicant’s arguments, but they are found unpersuasive.
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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/KELING ZHANG/
Primary Examiner
Art Unit 1732
Prosecution Insights