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 .
Response to Amendment
In response to the amendment received on 12/10/2025:
claims 1-21 are currently pending;
claims 16-21 are withdrawn;
the 112(b) rejection to claims 1-15 are withdrawn in light of the amendment to the claims; and
in the previous office action dated 08/11/2025, the 112(b) rejection to independent claim 1 specified the Examiners’ interpretation of claim 1 line 3 reciting “capturing carbon dioxide formed in while calcining cementitious precursors” is “capturing the carbon dioxide after calcining cementitious precursors” based on specification at [0027] and [0032]. Applicant’s response, submitted on 12/10/2025, indicated that the CNTs are produced on the same calcined cementitious precursors from which carbon dioxide is captured while calcining (see Applicant’s arguments at page 6, section Summary of Independent Claim 1), and amended claim 1 to recite “capturing carbon dioxide formed while calcining cementitious precursors”. Applicant’s response and amendment have changed the scope of the claimed limitations and have overcome the current grounds of rejection; however, new grounds of rejection are presented below.
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 1-9 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Eleto Da Silva et al. (US 2011/0107942 A1) (“Eleto” hereinafter) in view of Baier et al. (A cost estimation for CO2 reduction and reuse by methanation from cement industry sources in Switzerland, Frontiers in Energy Research, 2018) (“Baier” hereinafter); as evidenced by Noyes (US 2015/0059527 A1) (“Noyes” hereinafter) with respect to claim 1 and 8-9, and as evidenced by Stangeland et al. (CO2 Methanation: the effect of catalysts and reaction conditions, Energy Procedia, 2017) (“Stangeland” hereinafter) with respect to claim 11 only.
Regarding claim 1, Eleto teaches a method for generating carbon nanotube (CNT)-reinforced cementitious materials (see Eleto at [0001] teaching using cement clinker as nanoparticle anchoring base of transition metals allows carbon nanotubes to be generated on cement clinker particles and grains, in this way producing a kind of cement that is nanostructured with carbon nanotubes… by this process, the carbon nanotube synthesis and integration to clinker are carried out in just one continuous and large-scale stage, see Eleto at [0022] teaching the present disclosure describes a direct carbon nanotube/cement clinker synthesis by adding from 0.05% to 1% of carbon nanotubes onto cement clinker, in this way forming a carbon nanotubes/cement clinker composite, see Eleto at [0024]-[0025] teaching production of a nanostructured composite, rich in CNT, which can be used for several industrial applications, including the qualitative improvement of cement itself… the process described… produces a nanostructured composite of clinker containing CNT and basically involves… one… stages… 1 – a catalytic enrichment and activation method of basic cement clinker containing oxides or transition metal compounds so as to make it possible growing carbon nanotubes based on cement clinker components, see Eleto at [0027]-[0028] teaching therefore, this disclosure reports a process of a continuous production of carbon nanotubes using basic components of cement clinker as support matrix of transition metal nanoparticles, which promote carbon nanotubes growth… the aforesaid process also allows integrating carbon nanotubes to the traditional cement which are now recognized as fibrillar materials presenting exceptional mechanical resistance and in this way, improving significantly its physico-chemical properties). Cement containing CNT is taken to meet the claimed carbon nanotube (CNT)-reinforced cementitious materials. The process of a continuous production of carbon nanotubes using basic components of cement clinker is taken to meet the claimed teaches “a method for generating carbon nanotube (CNT)-reinforced cementitious materials”, comprising:
capturing carbon dioxide formed while calcining cementitious precursors; producing CNTs on the calcined cementitious precursors from the hydrocarbons (see Eleto at [0033]-[0034] teaching adding transition metal oxides… to clinker basic components called Catalytic Enrichment and Activation of Basic Portland Cement Clinker – can be made… before… clinker production, as follows… 1 – incorporating transition metals to clinker basic materials before the calcinations phase… oxides or transition metal compounds are added to clinker precursor materials, such as clay and limestone, before the calcination phase, see Eleto at [0048]-[0050] teaching the first phase would… involve a combination of cement powder or cement clinker to precursor transition metal compounds… with its calcination in oxidizing atmosphere at temperatures ranging from 300o C to 600o C… the second phase would involve a controlled introduction of such particle material into a rotary kiln of controlled atmosphere… into which an inert carrier gas is injected… and a carbon precursor gas, such as nonrestrictive natural gas, methane, ethylene, acetylene or propane… the aforesaid process of continuous large-scale synthesis of cement/carbon nanotubes composite allows controlling changes due to the said two basic components that enable controlled variations in the composite's physico-chemical features, which in turn allow a significant improvement of its applicability range for both structural and artistic reinforcement ends… the concentration of carbon nanotubes in relation, to clinker in the high temperature region may be controlled by the flow control, relative composition of involved gases and residence time of clinker in the high temperature region in said synthesis process). The calcination of limestone in a rotary kiln with transition metal compounds forming the cement/carbon nanotubes composite are taken to meet the claimed “capturing carbon dioxide formed while calcining cementitious precursors; producing CNTs on the calcined cementitious precursors from the hydrocarbons” because calcination of limestone liberates carbon dioxide that can be captured by the cementitious precursors and transition metal oxides to produce carbon nanotubes, as evidenced by Noyes (see Noyes at [0014] evidencing cement manufacture involves calcination, heating a raw material such as limestone (calcium carbonate) in a kiln, which liberates carbon dioxide, see Noyes at [0033] evidencing the methods disclosed herein produce solid carbon products… including carbon nanotubes… using carbon oxides present in offgas as the carbon source, see Noyes at [0029] evidencing the process offgas includes CO2… formed in a calciner… the term “offgas” means and includes any gas from any process that contains significant quantities of a carbon oxide (i.e., a higher concentration of CO2 and/or CO than is present in ambient air)… an offgas may be formed from heating limestone (CaCO3) to liberate CO2, as in the production of cements); and
forming CNT-reinforced, cementitious materials from the calcined cementitious precursors comprising the CNTs (see Eleto at [0039] teaching the said method consists in incorporating transition metal oxides… when preparing the clay and limestone mixture before calcination at oxidizing atmosphere for cement clinker formation… the mixture proportion is previously determined so as to produce a cement clinker with the desired concentration of microprecipitated phases onto cement clinker enriched with transition metals necessary to catalyze in situ synthesis reaction of carbon nanotubes, see Eleto at [0050] teaching the aforesaid process of continuous large-scale synthesis of cement/carbon nanotubes composite allows controlling changes due to the said two basic components that enable controlled variations in the composite's physico-chemical features, which in turn allow a significant improvement of its applicability range for both structural and artistic reinforcement ends… the concentration of carbon nanotubes in relation, to clinker in the high temperature region may be controlled by the flow control, relative composition of involved gases and residence time of clinker in the high temperature region in said synthesis process).
Eleto does not explicitly teach converting the carbon dioxide to hydrocarbons. However, as mentioned, Eleto teaches that catalytic conversion of carbon dioxide to carbon nanotubes is promoted by hydrocarbons, including alkanes such as CH4 (or methane) (see Eleto at [0048]-[0050]).
Like Eleto, Baier teaches that the calcination of limestone produces carbon dioxide (see Baier at page 2, right column, paragraph 2 teaching after waste incineration the cement industry, with an output of 2.5 million ton CO2 is the second largest emitter in the industrial sector… the waste gas (20-35% CO2 in variable N2 to O2 ratios) emitted by the cement industry is made up… and, secondly, from the CaCO3 dissociation of the feedstock… however, using these 2.5 million ton of mainly unavoidable CO2 would offer a possibility to replace large amounts of natural gas and reduce fossil imports with corresponding emissions, see Baier at page 2, right column, paragraph 4 to page 3, left column, paragraph 1 teaching the cement industry is conscious of the fact that it emits large amounts of CO2 and has been following various strategies for many years to counter these emissions… since only limited possibilities for further process optimizations are still available and since no alternative building material is going to exist for the near future, it is going to be necessary to consider additional approaches to reducing the high levels of CO2 emissions or to putting these to other uses… proposed reuse of the emitted CO2 in terms of its conversion to CH4 is one possible scenario to do so).
Baier further teaches particularly in industrial processes where CO2 emissions cannot currently be reduced through either substitution or renunciation, it would make sense to… produce a reusable waste product… this disclosure deals with making use of the climate-damaging gas CO2 for producing energy vector, i.e., methane (CH4) by applying the well-known Sabatier reaction for a power-to-gas application… and substitute fossil imports (see Baier at page 2, left column paragraph 3 to right column paragraph 1), which is taken to meet the claimed “converting the carbon dioxide to hydrocarbons” because methane is a hydrocarbon.
In summary, Baier teaches that it would make sense to use industrial CO2 emissions to produce methane by applying the well-known Sabatier reaction particularly for the cement industry that cannot currently reduce CO2 emission through either substitution or renunciation, and Eleto teaches that catalytic conversion of carbon dioxide to carbon nanotubes is promoted by hydrocarbons, including alkanes such as CH4 (or methane).
As such, one of ordinary skill in the art would appreciate that Baier teaches the industrial CO2 emissions to produce methane by applying the well-known Sabatier reaction particularly for the cement industry that cannot currently reduce CO2 emission through either substitution or renunciation, and seek those advantages by using methane from industrial CO2 emissions as taught by Baier in the direct carbon nanotube/cement clinker synthesis as taught by Eleto.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to use methane from industrial CO2 emissions as taught by Baier in the direct carbon nanotube/cement clinker synthesis as taught by Eleto because it would make sense to use industrial CO2 emissions to produce methane by applying the well-known Sabatier reaction particularly for the cement industry that cannot currently reduce CO2 emission through either substitution or renunciation, and Eleto teaches that catalytic conversion of carbon dioxide to carbon nanotubes is promoted by hydrocarbons, including alkanes such as CH4 (or methane).
Regarding claim 2, Eleto in view of Baier teach the limitations as applied to claim 1 above, and Eleto further teaches wherein the cementitious precursors comprise… tricalcium silicate (C3S) (see Eleto at [0029] teaching the basic components of cement clinker proved to be good anchor supports for transition metal nanoparticles, producing carbon nanotubes, see Eleto at [0009] teaching the major constituents of Portland cement clinker are: calcium silicates, called C3S (3CaO–SiO2)).
Regarding claims 3-4, Eleto in view of Baier teach the limitations as applied to claim 1 above, and Eleto further teaches comprising loading the calcined cementitious precursors with a catalyst (claim 3), and wherein the catalyst comprises… iron (claim 4) (see Eleto at [0029] teaching the basic components of cement clinker proved to be good anchor supports for transition metal nanoparticles, producing carbon nanotubes, see Eleto at [0035]-[0036] teaching the cement clinker enrichment with transition metals after calcination… carbon nanotubes synthesis is catalyzed by transition metal nanoparticles anchored in stable oxide support, see Eleto at [0038] teaching adding transition metals to cement clinker consists… in which transition metal salts and compounds… nonlimiting… Fe (or iron)).
Regarding claim 5, Eleto in view of Baier teach the limitations as applied to claims 1 and 3 above, and Eleto further teaches comprising reducing the catalyst to form catalyst particles on the calcined cementitious precursors (see Eleto at [0036] teaching carbon nanotubes synthesis is catalyzed by transition metal nanoparticles anchored in stable oxide support, see Eleto at [0038] teaching adding transition metals to cement clinker consists in a first process in which transition metal salts and compounds… are dissolved in polar, anhydride and volatile organic solvents… therefore, a liquid ionic solution of said salts and compounds is obtained in a water-free environment… this solution is then combined with cement clinker until a homogeneous mixture is obtained and then put into a kiln at temperatures… for the solvent volatization… then, the mixture is calcined in muffle kiln… in this way, clinker is impregnated with such transition metal oxides and becomes active for carbon nanotubes synthesis by chemical vapor-phase deposition). The formation of transition metal oxide nanoparticles combined with cement clinker after calcination is taken to meet the claimed “reducing the catalyst to form catalyst particles on the calcined cementitious precursors”.
Regarding claim 6, Eleto in view of Baier teach the limitations as applied to claims 1 and 3 above, and Eleto further teaches comprising forming the CNTs from the hydrocarbons by reaction of the hydrocarbons on a surface of the catalyst particles (see Eleto at [0043] teaching after this enrichment phase of cement clinker containing transition metals, this material is put into a rotary kiln of controlled and reducing atmosphere together with injection of a light hydrocarbon… such gaseous light hydrocarbons undergo a pyrolysis reaction at high temperatures and controlled atmosphere environment… the said pyrolysis reaction is catalyzed by the presence of transition metal nanoparticles described herein locally producing free carbon and Cx–Hy species responsible for carbon nanotubes growth… anchoring these nanoparticles in high stability compounds at high temperatures (high thermal stability oxide supports, such as Al.sub.2O.sub.3, SiO.sub.2, CaO, MgO or phases resulting from their combination) is an important measure for preventing the emergence of microprecipitates and agglomeration of such transition metal nanoparticles in a condition of carbon nanotubes synthesis by chemical vapor-phase deposition).
Regarding claim 7, Eleto in view Baier teach the limitations as applied to claims 1 and 3 above, and Eleto further teaches comprising: dissolving a transition metal salt in a solvent to form a catalyst solution (see Eleto at [0038] teaching adding transition metals to cement clinker consists in a first process in which transition metal salts and compounds… are dissolved in polar, anhydride and volatile organic solvents… therefore, a liquid ionic solution of said salts and compounds is obtained in a water-free environment), wherein the liquid ionic solution is taken to meet the claimed catalyst solution;
adding the catalyst solution to the cementitious precursor; and drying the catalyst solution to deposit the transition metal salt on the surface of the cementitious precursor (see Eleto at [0038] teaching the solution is then combined with cement clinker until a homogeneous mixture is obtained and then put into a kiln at temperatures… for the solvent volatization… then, the mixture is calcined in muffle kiln… in this way, clinker is impregnated with such transition metal oxides and becomes active for carbon nanotubes synthesis by chemical vapor-phase deposition).
Regarding claims 8-9, Eleto in view Baier teach the limitations as applied to claim 1 above, and Eleto further teaches comprising capturing the carbon dioxide by absorbing the carbon dioxide in a trap (claim 8), and wherein the trap comprises… metal oxides (claim 9) (see Eleto at [0039] teaching the said method consists in incorporating transition metal oxides… when preparing the clay and limestone mixture before calcination at oxidizing atmosphere for cement clinker formation… the mixture proportion is previously determined so as to produce a cement clinker with the desired concentration of microprecipitated phases onto cement clinker enriched with transition metals necessary to catalyze in situ synthesis reaction of carbon nanotubes). The transition metal oxides is taken to meet the claimed “trap” (claims 8-9), and is expected to be capable of capturing and absorbing the carbon dioxide from the calcination process of limestone. The calcination of limestone produces carbon dioxide, as evidenced by Noyes (see Noyes at [0014] evidencing cement manufacture involves calcination, heating a raw material such as limestone (calcium carbonate) in a kiln, which liberates carbon dioxide, see Noyes at [0033] evidencing the methods disclosed herein produce solid carbon products… including carbon nanotubes… using carbon oxides present in offgas as the carbon source, see Noyes at [0029] evidencing the process offgas includes CO2… formed in a calciner… the term “offgas” means and includes any gas from any process that contains significant quantities of a carbon oxide (i.e., a higher concentration of CO2 and/or CO than is present in ambient air)… an offgas may be formed from heating limestone (CaCO3) to liberate CO2, as in the production of cements).
Regarding claim 11, Eleto in view of Baier teach the limitations as applied to claim 1 above, and Baier further teaches comprising converting the carbon dioxide to hydrocarbons by performing a Sabatier reaction on the carbon dioxide to generate methane and water (see Baier at page 2, left column paragraph 3 to right column paragraph 1 teaching making use of the climate-damaging gas CO2 for producing energy vector, i.e., methane (CH4) by applying the well-known Sabatier reaction). Sabatier reaction is taken to meet the claimed limitations because Sabatier reaction produces methane and water from carbon dioxide and hydrogen as evidenced by Stangeland (see Stangeland at page 2023, paragraph 2 and section 2.1, paragraph 1, equation 1 evidencing methanation reaction, also called the Sabatier reaction… methanation of CO2 is an exothermic reaction in which H2 and CO2 react to form CH4 and H2O).
Claims 10 and 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Eleto in view Baier as applied to claim 1 above, and further in view of Noyes and ScienceDaily (Converting carbon dioxide to carbon monoxide using water, electricity, 2017) (“Daily” hereinafter).
Regarding claim 10, Eleto in view of Baier teach the limitations as applied to claim 1 above, and as mentioned, Baier teaches making use of the climate-damaging gas CO2 for producing energy vector, i.e., methane (CH4) by applying the well-known Sabatier reaction methane (see Baier at page 2, left column paragraph 3 to right column paragraph 1). But Eleto in view of Baier do not explicitly teach “performing an electrochemical reaction on the carbon dioxide with water to produce carbon monoxide”.
Like Eleto, Noyes teaches a carbon nanotube synthesis and integration to the cement clinker wherein the CNTs are catalytically converted from carbon dioxide and hydrocarbons (see Noyes at [0086] teaching in the calcining system 200… a portion of the solids 208 produced in the calciner… is mixed in a mixing vessel… with a portion of the solid carbon product 124 produced in the system 100… in other words, a portion of the solid carbon product 124 is a component of a cement of a cement product 218… the properties of the cement product 218 may vary based on the amount and type of the solid carbon product 124 added to the solids 208, see Noyes at [0082] teaching the calcining system 200 is configured to produce cement (e.g., Portland cement) or ingredients thereof… solids 208 produced in the calciner 206 may be referred to in the art as “clinker”, and may be further processed… to form a cement, such as cement based on calcium silicates, see Noyes at [0068] teaching in the system 100… the reactor… may catalytically convert CO and/or CO2 in the dried carbon oxide feedstock… to at least one solid carbon product… which may be separated from the catalyst and reaction gases in a separation unit associated with the reactor… a reducing agent… may be added to the reactor… to promote one or more reactions, including Bosch reactions… for example, the reducing agent… may include a hydrocarbon, see Noyes at [0033] teaching the methods disclosed herein produce solid carbon products… including carbon nanotubes… using carbon oxides present in offgas as the carbon source, see Noyes at [0029] teaching a process offgas is used as a feedstock to product solid carbon products… the process offgas includes CO2 or other gases formed in a calciner… as used herein, the term “offgas” means and includes any gas from any process that contains significant quantities of a carbon oxide (i.e., a higher concentration of CO2 and/or CO than is present in ambient air)… an offgas may be formed from heating limestone (CaCO3) to liberate CO2, as in the production of cements, including Portland cement).
Noyes further teaches concerns about greenhouse gases are encouraging industry and governments to find ways to minimize carbon dioxide production and its release into the atmosphere (see Noyes at [0015])… there is a spectrum of reactions involving carbon, oxygen, and hydrogen wherein various equilibria have been identified… hydrogen pyrolysis involves equilibria between hydrogen and carbon that favors solid carbon production (see Noyes at [0016)… the use of carbon oxides as a carbon source in production of solid carbon has largely been exploited… because point-source emissions have much higher concentrations of carbon dioxide than ambient air, however, they are often economical sources from which to harvest carbon dioxide (see Noyes at [0018]).
In summary, Noyes teaches that industrial carbon oxide offgas can be used as an economical source from which to harvest carbon dioxide so as to minimize carbon dioxide production and its release into the atmosphere.
Noyes further teaches the Bosch reaction of carbon dioxide and hydrogen to form… CNTs… is mildly exothermic (heat producing) and proceeds with the stoichiometry as shown in Equation 1:
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… the Bosch reactions are reversible… the Bosch reaction of Equation 1 is believed to be a two-step reaction with an overall release of energy (i.e., the reaction is exothermic)… in the first step of the reaction, carbon dioxide reacts with hydrogen to form carbon monoxide and water in a reverse water-gas shift reaction:
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… in the second step of the reaction, CO reacts with hydrogen in the presence of a catalyst to form solid carbon and water:).
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… the methane-reforming reactions, as described herein, include the reaction of methane with carbon dioxide or water:
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… the methane-reforming reactions produce carbon monoxide and hydrogen, which may form a gas stream suitable for Bosch reactions (see Noyes at [0034]-[0036]), which is taken to meet the claimed “comprising converting the carbon dioxide to hydrocarbons by… performing a reverse water gas shift reaction on the carbon monoxide with hydrogen to form methane”.
Like Noyes, Daily teaches forming CO from CO2 (see Daily at page 1, summary teaching researchers have determined how electrocatalysts can convert carbon dioxide to carbon monoxide using water and electricity… the discovery can lead to the development of efficient electrocatalysts for large scale production of synthesis gas – a mixture of carbon monoxide and hydrogen). The conversion of carbon dioxide to carbon monoxide using water and electricity is taken to meet the claimed “performing an electrochemical reaction on the carbon dioxide with water to produce carbon monoxide”.
Daily further teaches the electrochemical reduction of carbon dioxide to fuels is a subject of considerable interest because it offers a means for storing electricity from energy sources such as wind and solar radiation in the form of chemical bond (see Daily at page 1, paragraph 2)… “once you recognize how these reaction are occurring on electrocatalysts, you can control the catalysts structure and operating conditions to produce carbon monoxide efficiently,” Singh said… since they are product gases – carbon monoxide and hydrogen are insoluble in aqueous electrolytes – they can be readily separated as synthesis gas and converted into fuels such as… a mixture of hydrocarbons (see Daily at page 2, paragraph 7).
As such, one of ordinary skill in the art would appreciate that Daily teaches that electrocatalyst can convert carbon dioxide to carbon monoxide using water and electricity that could lead to large scale production of synthesis gas and converted into a mixture of hydrocarbons, and Noyes teaches industrial carbon oxide offgas can be used as an economical source from which to harvest carbon dioxide so as to minimize carbon dioxide production and its release into the atmosphere. One of ordinary skill in the art can seek those advantages by using an electrocatalyst that convert carbon dioxide to carbon monoxide using water and electricity in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to use an electrocatalyst that convert carbon dioxide to carbon monoxide using water and electricity as taught by Daily in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier because industrial carbon oxide offgas can be used as an economical source from which to harvest carbon dioxide so as to minimize carbon dioxide production and its release into the atmosphere as taught by Noyes. Additionally, electrocatalyst could lead to large scale production of synthesis gas and converted into a mixture of hydrocarbons.
Regarding claims 14-15, Eleto in view of Noyes and Baier teach the limitations as applied to claim 1 above, but Eleto in view of Baier do not explicitly teach comprising: forming hydrogen during formation of the carbon nanotubes; and recycling the hydrogen to form hydrocarbons from carbon dioxide (claim 14), and comprising using a portion of the hydrogen to assist in forming the CNTs (claim 15). Please see claim 10 rejection based on Noyes as it applies here as well.
However, Eleto teaches that the concentration of carbon nanotubes in relation, to clinker in the high temperature region may be controlled by the flow control, relative composition of involved gases and residence time of clinker in the high temperature region in said synthesis process (see Eleto at [0050]).
Noyes teaches that there is a spectrum of reactions involving carbon, oxygen, and hydrogen wherein various equilibria have been identified… hydrocarbon pyrolysis involves equilibria between hydrogen and carbon that favors solid carbon production, typically with little or no oxygen present… the Boudouard reaction, also called the "carbon monoxide disproportionation reaction," is the range of equilibria between carbon and oxygen that favors solid carbon production, typically with little or no hydrogen present… the Bosch reaction is within a region of equilibria where all of carbon, oxygen, and hydrogen are present under reaction conditions that also favor solid carbon production (see Noyes at [0016]). And, Noyes teaches that the relationship between the hydrocarbon pyrolysis, Boudouard, and Bosch reactions may be understood in terms of a C–H–O equilibrium diagram, as shown in FIG. 1 (shown below)… the C–H–O equilibrium diagram of FIG. 1 shows various known routes to solid carbon, including, carbon nanotubes ("CNTs")… the hydrocarbon pyrolysis reactions occur on the equilibrium line that connects H and C and in the region near the left edge of the triangle to the upper left of the dashed lines… two dashed lines are shown because the transition between the pyrolysis zone and the Bosch reaction zone may change with reactor temperature (see Noyes at [0017]).
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Furthermore, Noyes teaches the methods utilize Bosch reactions to produce solid carbon products and water by the reduction of carbon dioxide or carbon monoxide with hydrogen, hydrocarbons, alcohols, or mixtures thereof… reaction conditions may be optimized to produce a selected type of solid carbon… the catalytic conversion process may include a variety of separation technologies to remove the solid carbon and water and may include recycling the tail gases with makeup gases added as necessary… the methods disclosed herein include reactions in the interior region of the phase diagram shown in FIG. 1, including multi-step reactions (e.g., methane-reforming reactions, followed by reactions in the Bosch reaction zone), where equilibrium may be established between solid carbon, oxygen, hydrogen, and compounds of carbon, hydrogen and/or oxygen… the central region of FIG. 1 has several points favorable for the formation of CNTs and other allotropes and associated morphologies of solid carbon… the type of solid carbon produced may be selectively controlled through selection and processing of the catalysts, reaction gas mixtures, and reaction conditions… thus, these methods open new routes to the processing of carbon-containing gases and the production of valuable solid carbon products such as CNTs (see Noyes at [0027]-[0028]). Moreover, Noyes teaches the Bosch reactions, as disclosed herein, use hydrogen, hydrocarbons, alcohols, or mixtures thereof to reduce carbon oxides (e.g., carbon dioxide, carbon monoxide, or mixtures thereof) to solid carbon (e.g.… single-wall CNTs, multi-wall CNTs…) and water… these reactions may be conducted at temperatures from approximately 450 oC to approximately 1,000 oC in the presence of a catalyst such as iron… the Bosch reaction of carbon dioxide and hydrogen to form… CNTs… is mildly exothermic (heat producing) and proceeds with the stoichiometry as shown in Equation 1:
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… the Bosch reactions are reversible… the Bosch reaction of Equation 1 is believed to be a two-step reaction with an overall release of energy (i.e., the reaction is exothermic)… in the first step of the reaction, carbon dioxide reacts with hydrogen to form carbon monoxide and water in a reverse water-gas shift reaction:
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… in the second step of the reaction, CO reacts with hydrogen in the presence of a catalyst to form solid carbon and water:
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… the methane-reforming reactions, as described herein, include the reaction of methane with carbon dioxide or water:
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… the methane-reforming reactions produce carbon monoxide and hydrogen, which may form a gas stream suitable for Bosch reactions… the methane-reforming reactions typically occur at temperatures higher than temperatures at which Bosch reactions occur… in some embodiments, the methane-reforming reactions may precede Bosch reactions to supply hydrogen and carbon monoxide for Bosch reactions… because methane-reforming reactions typically occur at higher temperatures than Bosch reactions, it may be desirable to add a cooler carbon oxide steam to gases flowing from methane-reforming reactions and cool the resulting mixed gas stream to a temperature suitable for subsequent Bosch reactions (see Noyes at [0034]-[0036]).
As such, one of ordinary skill in the art would appreciate that the equilibrium between solid carbon and hydrogen as taught by Noyes that include reactions in the interior region of the phase diagram shown in FIG. 1, including multi-step reactions (e.g., methane-reforming reactions, followed by reactions in the Bosch reaction zone) are result effective variables that could be optimized so as to provide the desired carbon nanotubes and hydrocarbons from the hydrogen and carbon dioxide in the direct carbon nanotube/cement clinker synthesis as taught by Eleto and Baier, and meet the claimed “forming hydrogen during formation of the carbon nanotubes; and recycling the hydrogen to form hydrocarbons from carbon dioxide” (claim 14), and “comprising using a portion of the hydrogen to assist in forming the CNTs” (claim 15). The equilibrium between solid carbon and hydrogen as taught by Noyes is consistent with the teaching outlined by Eleto that the concentration of carbon nanotubes in relation, to clinker in the high temperature region may be controlled by the flow control, relative composition of involved gases and residence time of clinker in the high temperature region in said synthesis process (see Eleto at [0050]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have optimized the equilibrium between solid carbon and hydrogen as outlined by the methods as taught by Noyes that include reactions in the interior region of the phase diagram shown in FIG. 1, including multi-step reactions (e.g., methane-reforming reactions, followed by reactions in the Bosch reaction zone) so as to provide the desired carbon nanotubes and hydrocarbons from the hydrogen and carbon dioxide in the direct carbon nanotube/cement clinker synthesis as taught by Eleto and Baier, and meet the claimed “forming hydrogen during formation of the carbon nanotubes; and recycling the hydrogen to form hydrocarbons from carbon dioxide” (claim 14), and “comprising using a portion of the hydrogen to assist in forming the CNTs” (claim 15).
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Eleto in view of Baier as applied to claim 1 above, and further in view of Blasco-Gómez et al. (On the edge of research and technological application: a critical review of electromethanogenesis, International Journal of Molecular Sciences, 2017) (“Blasco” hereinafter).
Regarding claim 12, Eleto in view of Baier teach the limitations as applied to claim 1 above, and as mentioned, Baier teaches making use of the climate-damaging gas CO2 for producing energy vector, i.e., methane (CH4) by applying the well-known Sabatier reaction methane (see Baier at page 2, left column paragraph 3 to right column paragraph 1).
Eleto in view of Baier do not explicitly teach comprising converting the carbon dioxide to hydrocarbons by electromethanogenesis.
Like Baier, Blasco teaches Sabatier reaction (see Blasco at page 1, paragraph 1 teaching methane is produced by either natural thermal splitting of kerogen contained in sedimentary rocks or catalytic formation (equations (1) and (2))… both are reversible, exothermic and catalyst-dependent reactions… in industry, reaction 1 is used to produce synthetic methane-rich fuel from syngas, whereas reaction 2 was discovered in the early 1900s by Paul Sabatier and required elevated temperatures, high pressure and the presence of metal catalyst). Blasco further teaches recently, the bioelectrochemical reduction of carbon dioxide (CO2) has been postulated as a promising process to obtain methane… in this case, CO2 can be either directly reduced by providing electrons as a reducing power (equation (3)) or by means of the in situ production of hydrogen (H2) – an electron donor for hydrogenotrophic methanogenesis – which act as a catalyst (equation (2)) to reduce the large overpotentials affecting the reaction (see Blasco at page 2, paragraph 2). Furthermore, Blasco teaches the term electromethanogenesis was first used to refer to an alternative methanogenic pathway… where CO2 is reduced by a single Archaeon… using electrical current supplied to the reactor (see Blasco at page 2, paragraph 3), which is taken to meet the claimed “comprising converting the carbon dioxide to hydrocarbons by electromethanogenesis”.
Furthermore, Blasco teaches the conversion of electrical current into methane (electromethanogenesis) by microbes represents one of the most promising applications of bioelectrochemical systems (BES)… electromethanogenesis provides a novel approach to… carbon dioxide fixation and renewable energy storage into a chemically stable compound, such as methane (see Blasco at Abstract).
As such, one of ordinary skill in the art would appreciate that Blasco teaches that electromethanogenesis is a novel approach to carbon dioxide fixation and renewable energy storage into a chemically stable compound, such as methane, and seek those advantages by replacing Sabatier reaction with electromethanogenesis in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to replace Sabatier reaction with electromethanogenesis as taught by Blasco in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier because electromethanogenesis is a novel approach to carbon dioxide fixation and renewable energy storage into a chemically stable compound, such as methane.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Eleto in view of Baier as applied to claim 1 above, and further in view of Sheehan (Electrochemical methane production from CO2 for orbital and interplanetary refueling, Cell Press, 2021) (“Sheehan” hereinafter).
Regarding claim 13, Eleto in view of Baier teaches the limitations as applied to claim 1 above, and as mentioned, Baier teaches making use of the climate-damaging gas CO2 for producing energy vector, i.e., methane (CH4) by applying the well-known Sabatier reaction methane (see Baier at page 2, left column paragraph 3 to right column paragraph 1).
Eleto in view of Baier do not explicitly teach comprising electrochemically reducing the carbon dioxide to hydrocarbons.
Like Baier, Sheehan teaches Sabatier reaction (see Sheehan at pages 3-4 bridging paragraph teaching both the thermocatalytic Sabatier process and the electrocatalytic process face challenges that ultimately affect their technoeconomics and viability for deployment… going forward, as more robust and efficient CO2 electrolysis systems are engineered, their lower operational temperatures and pressures provide an opportunity to decrease system weight as compared with the Sabatier).
Sheehan also teaches at a high level, there are two abiotic methods that can be used to produce methane from carbon dioxide, water, and electricity… in the direct electrochemical scheme, the cathodic CO2 electroreduction half-reaction is coupled with a corresponding half-reaction that provides the requisite protons and electrons to form CH4 (see Sheehan at page 3, paragraph 1), which is taken to meet the claimed “comprising electrochemically reducing the carbon dioxide to hydrocarbons”.
As such, one of ordinary skill in the art would appreciate that Sheehan teaches that more robust and efficient CO2 electrolysis lower operational temperatures and pressures that provide an opportunity to decrease system weight as compared with the Sabatier, and seek those advantages by replacing Sabatier reaction with a more robust and efficient CO2 electrolysis in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to replace Sabatier reaction with a more robust and efficient CO2 electrolysis as taught by Sheehan in the direct carbon nanotube/cement clinker synthesis as taught by Eleto in view of Baier because CO2 electrolysis lower operational temperatures and pressures that provide an opportunity to decrease system weight as compared with the Sabatier.
Response to Arguments
Applicant’s response to 112 rejection and amendments to independent claim 1 have obviated the rejection based on the teachings of Eleto in view of Noyes and Baier. However, upon further consideration, a new ground of rejection is set forth for the amended claim 1 based on Eleto in view of Baier, as outlined above. Thus, relevant arguments are addressed below.
Applicant discusses that the cited portion of Eleto have not been shown to describe that the “calcined cementitious precursors” on which “the calcined cementitious precursors” on which “the CNTs” are produced are the same “cementitious precursors” from which “carbon dioxide” was captured “while calcining [the] cementitious precursors”… although Eleto describes “a direct carbon nanotube/cement clinker synthesis”, Eleto does not describe or suggest that the carbon dioxide to produce the carbon nanotube is captured when the cement clinker is calcined (see Applicant’s arguments at page 6 paragraph 4 to page 7 paragraph 1).
Examiner acknowledges the arguments and respectfully notes that, as outlined above, Eleto teaches the method consists in incorporating transition metal oxides when preparing the clay and limestone mixture before calcination at oxidizing atmosphere for cement clinker formation in situ synthesis reaction of carbon nanotubes (see Eleto at [0039] and [0048]-[0050], and claims 1 and 8-9 rejections above). The transition metal oxides is taken to meet the claimed limitations because the oxides absorbs or traps the carbon dioxide from the calcination process of limestone. Limestone calcination produces carbon dioxide, as evidenced by Noyes (see Noyes at [0014] evidencing cement manufacture involves calcination, heating a raw material such as limestone (calcium carbonate) in a kiln, which liberates carbon dioxide, see Noyes at [0033] evidencing the methods disclosed herein produce solid carbon products… including carbon nanotubes… using carbon oxides present in offgas as the carbon source, see Noyes at [0029] evidencing the process offgas includes CO2… formed in a calciner… the term “offgas” means and includes any gas from any process that contains significant quantities of a carbon oxide (i.e., a higher concentration of CO2 and/or CO than is present in ambient air)… an offgas may be formed from heating limestone (CaCO3) to liberate CO2, as in the production of cements). Eleto in view of Baier have reasonably met the claimed limitations. As such, the rejection to independent claim 1 is maintained.
Applicant discusses that Baier does not remedy the deficiencies of the portions of Eleto and Noyes, or the proposed combination of Eleto, Noyes and Baier has not shown to describe or suggest that cementitious precursors are calcined to produce carbon dioxide, which is captured, and the CNTs are produced on the same calcined cementitious precursors from which carbon dioxide is captured… portions of Stangeland, Weissman, Daily, Blasco and Sheehan have not been cited as remedying the deficiencies of the proposed combination of Eleto, Noyes and Baier (see Applicant’s arguments at page 8, paragraphs 2-3).
Examiner acknowledges the arguments, and as mentioned above, Eleto in view of Baier have reasonably met the claimed limitations. As such, the rejection to independent claim 1 is maintained.
Applicant discusses that the Office Action has not shown that the limitations of claim 14 are not met my Eleto, Noyes and Baier because the quoted portions from page 18 of the Office Action are merely inferences and conclusory statements by the Office… the Office action has not shown that Noyes or any other references describes that the hydrogen, which is formed during formation of the carbon nanotubes, is recycled to form hydrocarbons from carbon dioxide (see Applicants arguments at page 8, paragraph 4 to page 9, paragraph 3).
Examiner acknowledges the arguments and respectfully notes that in the new rejection above, the equilibrium between solid carbon and hydrogen as taught by Noyes that include reactions in the interior region of the phase diagram shown in FIG. 1, including multi-step reactions (e.g., methane-reforming reactions, followed by reactions in the Bosch reaction zone) are result effective variables that could be optimized so as to provide the desired carbon nanotubes and hydrocarbons from the hydrogen and carbon dioxide in the direct carbon nanotube/cement clinker synthesis as taught by Eleto and Baier, and meet the claimed “forming hydrogen during formation of the carbon nanotubes; and recycling the hydrogen to form hydrocarbons from carbon dioxide” (claim 14), and “comprising using a portion of the hydrogen to assist in forming the CNTs” (claim 15). The combination of Eleto, Baier and Noyes has reasonably met the claimed limitations of claim 14. As such, the rejection to claim 14 is maintained.
Applicant requested a telephone conference with the Examiner and further requested the Examiner to contact the undersigned attorney if the present application is not allowed and/or if one or more of the rejections is maintained (see Applicant’s arguments at page 9 paragraph 4).
Examiner respectfully notes that examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice; communications should be directed to MARITES A GUINO-O UZZLE whose telephone number is (571)272-1039. The examiner can normally be reached M-F 8am-4pm EST. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Amber R Orlando can be reached at (571)270-3149.
Applicant requests consideration of all filed IDS not previously considered, by initialing and returning each Form PTO-1149 (see Applicant’s arguments at page 10, paragraph 10).
Examiner notes that there are no new filed IDS. The earlier filed IDS submitted on 06/23/2023 was considered on 07/30/2025 and attached in the previous office action dated 08/11/2025.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARITES A GUINO-O UZZLE whose telephone number is (571)272-1039. The examiner can normally be reached M-F 8am-4pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Amber R Orlando can be reached at (571)270-3149. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MARITES A GUINO-O UZZLE/Examiner, Art Unit 1731