DETAILED ACTION
In response to remarks filed on 17 December 2025
Status of Claims
Claims 8-20 are pending;
Claims 8-20 were previously presented;
Claims 1-7 are withdrawn;
Claims 8-20 are rejected herein.
Response to Arguments
Applicant’s arguments filed on 17 December 2025 have been fully considered and they are not persuasive. Regarding the “storing the carbon dioxide phase and the nonionic surfactant as a combined phase within the subterranean formation” limitation, examiner cited paragraph 0033 to show that the mixture is located underground regardless of the behavior described. “Storing” is a broad and relative term. “Storage” can be for a few seconds, a few minutes, a few hours, months, years which is why the term is relative. In this case the behavior described by paragraph 0033 happens while the mixture is stored/placed underground in the subterranean formation. The claim does not provide details regarding the storage.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 8, 14 and 16-19 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Sanders et al (U.S. Patent Application Publication No. 2014/0251607).
As to Claim 8, Sanders discloses a method comprising:
Combining a carbon dioxide phase and a nonionic surfactant, such that the nonionic surfactant is at least partially dissolved in the carbon dioxide phase, the nonionic surfactant comprising a first polyalkoxylated alcohol and a second polyalkoxylated alcohol, in which each polyalkoxylated alcohol is a reaction product of an aliphatic alcohol and one or more of ethylene oxide, propylene oxide, and butylene oxide (Paragraph 0036: “Using a mixture of the aliphatic branched alcohols to create the nonionic surfactants of the present disclosure is also possible”; Paragraph 0043: “The nonionic surfactant of the present disclosure provides a water soluble component and a carbon dioxide soluble (water insoluble) component. While not wishing to be bound by theory, it is believed that the propylene oxide used in forming the nonionic surfactant, along with the branched aliphatic alcohol, provides the carbon dioxide soluble (water insoluble) component of the nonionic surfactant, while the ethylene oxide used in forming the nonionic surfactant provides the water soluble component of the nonionic surfactant. To modify the carbon dioxide and/or the water soluble portions, changes in the molar amount of the propylene oxide and ethylene oxide used in the nonionic surfactant and/or the low molecular weight branched aliphatic alcohol used can be made”);
Introducing the carbon dioxide phase and the nonionic surfactant into a subterranean formation (Paragraph 0048: “In an alternative example, it is also possible to inject the nonionic surfactant with the diluent into the subterranean formation via the injection well followed by injecting the carbon dioxide into the subterranean formation (i.e., the carbon dioxide is injected after the nonionic surfactant with the diluent is injected into the subterranean formation) to generate the foam. In addition, in some embodiments, the nonionic surfactant can be injected into the reservoir with both the diluent and carbon dioxide to generate the foam, where the nonionic surfactant can be included in either the carbon dioxide and/or the diluent. The foam can also be created before being injected into the subterranean formation by stirring the diluent and the nonionic surfactant and injecting it into the subterranean reservoir”); and
Storing the carbon dioxide phase and the nonionic surfactant as a combined phase within the subterranean formation (Paragraph 0033: “So, instead of spreading out through the underground formation, the carbon dioxide finds the fastest way through the formation. If, however, the carbon dioxide were made to behave in a more viscous manner, it could be made to spread out and slow down thereby contacting more of the underground formation. This would lead to more contact of the carbon dioxide with the crude oil in the underground formation”).
As to Claim 14, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Sanders also discloses wherein the carbon dioxide phase comprises liquid carbon dioxide, an aqueous carbon dioxide solution, or any combination thereof (Paragraph 0029: “The foam can include the nonionic surfactant, carbon dioxide (CO.sub.2) in a liquid or supercritical phase, and a diluent, where the nonionic surfactant promotes a formation of the foam of the carbon dioxide, the diluent and the nonionic surfactant”).
As to Claim 16, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Sanders also discloses wherein the carbon dioxide phase is introduced to the subterranean formation before the nonionic surfactant (Paragraph 0048: “In an alternative example, it is also possible to inject the nonionic surfactant with the diluent into the subterranean formation via the injection well followed by injecting the carbon dioxide into the subterranean formation (i.e., the carbon dioxide is injected after the nonionic surfactant with the diluent is injected into the subterranean formation) to generate the foam. In addition, in some embodiments, the nonionic surfactant can be injected into the reservoir with both the diluent and carbon dioxide to generate the foam, where the nonionic surfactant can be included in either the carbon dioxide and/or the diluent. The foam can also be created before being injected into the subterranean formation by stirring the diluent and the nonionic surfactant and injecting it into the subterranean reservoir”).
As to Claim 17, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Sanders also discloses wherein the nonionic surfactant is introduced to the subterranean formation before the carbon dioxide phase (Paragraph 0048: “In an alternative example, it is also possible to inject the nonionic surfactant with the diluent into the subterranean formation via the injection well followed by injecting the carbon dioxide into the subterranean formation (i.e., the carbon dioxide is injected after the nonionic surfactant with the diluent is injected into the subterranean formation) to generate the foam. In addition, in some embodiments, the nonionic surfactant can be injected into the reservoir with both the diluent and carbon dioxide to generate the foam, where the nonionic surfactant can be included in either the carbon dioxide and/or the diluent. The foam can also be created before being injected into the subterranean formation by stirring the diluent and the nonionic surfactant and injecting it into the subterranean reservoir”).
As to Claim 18, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Sanders also discloses wherein the nonionic surfactant and carbon dioxide phase are introduced to the subterranean formation concurrently (Paragraph 0048: “In an alternative example, it is also possible to inject the nonionic surfactant with the diluent into the subterranean formation via the injection well followed by injecting the carbon dioxide into the subterranean formation (i.e., the carbon dioxide is injected after the nonionic surfactant with the diluent is injected into the subterranean formation) to generate the foam. In addition, in some embodiments, the nonionic surfactant can be injected into the reservoir with both the diluent and carbon dioxide to generate the foam, where the nonionic surfactant can be included in either the carbon dioxide and/or the diluent. The foam can also be created before being injected into the subterranean formation by stirring the diluent and the nonionic surfactant and injecting it into the subterranean reservoir”).
As to Claim 19, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Sanders also discloses wherein the nonionic surfactant is present in an aqueous fluid that is combined with the carbon dioxide phase (Paragraph 0016: “As used herein, the term "diluent" can include, for example, water, brine, connate water, surface water, distilled water, carbonated water, sea water and combinations thereof. For brevity, the word "diluent" will be used herein, where it is understood that one or more of "water," "brine," "connate water," "surface water," "distilled water," "carbonated water," and/or "sea water" can be used interchangeably”; Paragraph 0029: “The foam can include the nonionic surfactant, carbon dioxide (CO.sub.2) in a liquid or supercritical phase, and a diluent, where the nonionic surfactant promotes a formation of the foam of the carbon dioxide, the diluent and the nonionic surfactant”).
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.
Claims 9 and 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sanders et al (U.S. Patent Application Publication No. 2014/0251607) in view of Kubala et al (U.S. Patent Application Publication No. 2009/0260828).
As to Claim 9, Sanders discloses the invention of Claim 8 (Refer to Claim 9 discussion). However, Sanders is silent about wherein the combined phase is stored within the subterranean formation as a carbon dioxide hydrate, a mixed carbon dioxide hydrate, or any combination thereof. Kubala discloses that subterranean formations bearing hydrocarbon materials typically contain methane, hydrates, clathrates (Paragraphs 0015 and 0016: “Coal beds and hydrocarbon-bearing, shale-containing formations typically contain methane (CH4) and small amounts of other light hydrocarbon gases. Carbon dioxide (CO2) is known to displace methane from lattice structures, such as methane gas hydrates, methane THF clathrates, etc., and adsorbed methane from the surfaces, pore spaces, interstices, seams, etc. of the formation. This is contrasted with other gases, such as nitrogen or air that do not show a preferential tendency to displace the absorbed or latticed methane. Coal beds and gas hydrates, in particular, show preferential adsorption of or replacement by CO2 compared to methane. By injecting a carbon-dioxide treatment fluid into such formations at a pressure above the fracture pressure of the formation, the formations can be effectively fractured to stimulate production of methane and other hydrocarbon gases. The fracturing relieves stresses in the formation, decaps trapped gases and creates pore spaces and channels for the flow of gas from the formation into the wellbore. Additionally, because of the preferential displacement of absorbed or latticed methane by CO2, further methane is evolved from the treatment than would otherwise occur with other fracturing treatments or with the use of other gases. The use of CO2 also provides longer term enhancement of the overall gas production due the carbon dioxide's ability to displace methane”). Before the effective filing date of the invention, it would have been obvious to a person of ordinary skill in the art to inject the carbon dioxide-based treatment fluid of Sanders in an underground formation containing methane thereby resulting in a carbon dioxide hydrate, a mixed carbon dioxide hydrate, or any combination thereof. The motivation would have been to increase the utility of the fluid by also using it to displace and recover methane.
As to Claim 10, Sanders discloses the invention of Claim 8 (Refer to Claim 9 discussion). However, Sanders is silent about wherein the subterranean formation contains an existing gas hydrate or comprises a hydrate zone. Kubala discloses that subterranean formations bearing hydrocarbon materials typically contain methane, hydrates and/or clathrates (Paragraphs 0015 and 0016: “Coal beds and hydrocarbon-bearing, shale-containing formations typically contain methane (CH4) and small amounts of other light hydrocarbon gases. Carbon dioxide (CO2) is known to displace methane from lattice structures, such as methane gas hydrates, methane THF clathrates, etc., and adsorbed methane from the surfaces, pore spaces, interstices, seams, etc. of the formation. This is contrasted with other gases, such as nitrogen or air that do not show a preferential tendency to displace the absorbed or latticed methane. Coal beds and gas hydrates, in particular, show preferential adsorption of or replacement by CO2 compared to methane. By injecting a carbon-dioxide treatment fluid into such formations at a pressure above the fracture pressure of the formation, the formations can be effectively fractured to stimulate production of methane and other hydrocarbon gases. The fracturing relieves stresses in the formation, decaps trapped gases and creates pore spaces and channels for the flow of gas from the formation into the wellbore. Additionally, because of the preferential displacement of absorbed or latticed methane by CO2, further methane is evolved from the treatment than would otherwise occur with other fracturing treatments or with the use of other gases. The use of CO2 also provides longer term enhancement of the overall gas production due the carbon dioxide's ability to displace methane”). Before the effective filing date of the invention, it would have been obvious to a person of ordinary skill in the art to inject the carbon dioxide-based treatment fluid of Sanders in a subterranean formation containing an existing gas hydrate or a hydrate zone. The motivation would have been to increase the utility of the fluid by also using it to displace and recover clathrates.
Claims 11, 12, 15 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sanders et al (U.S. Patent Application Publication No. 2014/0251607) alone.
As to Claim 11, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). However, Sanders does not explicitly disclose wherein the first polyalkoxylated alcohol has a structure represented by
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wherein R1 is a C2 to C20 straight-chain or branched alkyl group; A is A1, A2, or A3, and A1 is —CH2CH2—, A2 is —CH2CH(CH3)—, and A3 is —CH2CH(CH2CH3)—; x is an integer ranging from 2 to 40, and there are a3 occurrences of A3 in the first polyalkoxylated alcohol, a2 occurrences of A2 in the first polyalkoxylated alcohol, and a1 occurrences of A1 in the first polyalkoxylated alcohol; wherein a3 is an integer ranging from 0 to 5, a2 is an integer ranging from 0 to 10, a1 is an integer ranging from 1 to 25, and a1=x−(a2+a3); and wherein the second polyalkoxylated alcohol has a structure represented by
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wherein R2 is a C2 to C20 straight-chain or branched alkyl group; B is B1, B2, or B3, and B1 is —CH2CH2—, B2 is —CH2CH(CH3)—, and B3 is CH2CH(CH2CH3)—; y is an integer ranging from x+4 to 65, and there are b3 occurrences of B3 in the second polyalkoxylated alcohol, b2 occurrences of B2 in the second polyalkoxylated alcohol, and b1 occurrences of B1 in the first polyalkoxylated alcohol; wherein b3 is an integer ranging from 0 to 5, b2 is an integer ranging from 0 to 10, b1 is an integer ranging from a1+4 to 50, and b1=y−(b2+b3). Before the effective filing date of the invention, it would have been obvious to a person of ordinary skill in the art to make the first polyalkoxylated alcohol of the structure previously mentioned since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. It is also common knowledge to choose a material that has sufficient strength, durability, flexibility, hardness, etc. for the application and intended use of that material.
As to Claim 12, Sanders as modified teaches the invention of Claim 11 (Refer to Claim 11 discussion). However, Sanders as modified does not explicitly teach wherein a1>a2 and/or b1>b2. Before the effective filing date of the invention, it would have been obvious to a person of ordinary skill in the art to make the first polyalkoxylated alcohol of the structure previously mentioned but with a1>a2 and/or b1>b2 since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. It is also common knowledge to choose a material that has sufficient strength, durability, flexibility, hardness, etc. for the application and intended use of that material.
As to Claim 15, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). Although Sanders does not explicitly disclose wherein the combined phase has a mass ratio of aqueous fluid to carbon dioxide ranging from about 1:5 to about 1:30, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to contrive any number of desirable ranges for the mass ratio limitation, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art.
As to Claim 20, Sanders discloses the invention of Claim 19 (Refer to Claim 19 discussion). Although Sanders does not explicitly disclose wherein a concentration of the nonionic surfactant in the aqueous fluid ranges from about 0.1 wt% to about 5.0 wt% based on total mass, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to contrive any number of desirable ranges for the concentration limitation, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art.
Claim 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sanders et al (U.S. Patent Application Publication No. 2014/0251607) in view of Nguyen (U.S. Patent Application Publication No. 2007/0114022).
As to Claim 13, Sanders discloses the invention of Claim 8 (Refer to Claim 8 discussion). However, Sanders is silent about further comprising introducing a preflush fluid to the subterranean formation prior to introducing the carbon dioxide phase and the nonionic surfactant, the preflush fluid comprising an aqueous fluid. Nguyen discloses introducing a preflush fluid to a subterranean formation (Paragraph 0026: “Typically, injection of a preflush fluid may occur at any time before the consolidating agent is introduced into the slot in the unconsolidated portion of the subterranean formation. In certain embodiments, a preflush fluid may be used, among other purposes, to clean out undesirable substances (e.g., oil, residue, or debris) from the pore spaces in the subterranean formation, to clean out such undesirable substances residing in perforations or holes in a casing string, and/or to prepare the subterranean formation for subsequent placement of the consolidating agent”). Before the effective filing date of the invention, it would have been obvious to a person of ordinary skill in the art to introduce a preflush fluid to the subterranean formation prior to introducing the carbon dioxide phase and the nonionic surfactant, the preflush fluid comprising an aqueous fluid. The motivation would have been to clean out undesirable substances.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to EDWIN J TOLEDO-DURAN whose telephone number is (571)270-7501. The examiner can normally be reached Monday through Friday: 10:00AM to 6:00PM EST.
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/EDWIN J TOLEDO-DURAN/Primary Examiner, Art Unit 3678