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 .
Priority
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application No. CN202311640493, filed on December 1, 2023.
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Specification
The disclosure is objected to because of the following informalities: Page 3, line 21 “… a total concentration of Ca2+ and Mg2+…” there is no associated value for the total concentration outside of the mention in the prior paragraph not exceeding 5000mg/L.
Appropriate correction is required.
Claim Objections
Claim 8 is objected to because of the following informalities: claim 8 reads as being dependent "according to any of claim 1" which is understood to be a typing error to avoid multiple dependencies. Claim 8 should as "according to claim 1" and will be interpreted as such for the purposes of examination. Appropriate correction is required.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
Claims 8-10 are rejected under 35 U.S.C. 101 because the claimed invention is directed to non-statutory subject matter. The claim(s) does/do not fall within at least one of the four categories of patent eligible subject matter because the use claim 8 does not have a process step to be a proper process of use claim.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 3-10 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “slowly” in claim 3 is a relative term which renders the claim indefinite. The term “slowly” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Claim 3 involves a step of "adding slowly tetrabutyl titanate and ammonia solution" but there is no clarification as to what qualifies as "slowly" adding such reagents. Thus, Claim 3 is indefinite. Claims 4-7 are rejected as being dependent on, and failing to cure the deficiencies of, rejected dependent claim 3. For the purposes of examination, “adding slowly” will be interpreted as a dropwise addition of aqueous reagents.
Claim 6 is indefinite due to the “… a total concentration of Ca2+ and Mg2+…” in the fourth line of the claim is left undefined. There is no clear limitation to what this total concentration should be as the clause afterwards refers to a total salinity not exceeding 90,000 mg/L which would invalidate the prior limitation of claim 5 on which claim 6 is dependent upon whereby the Ca and Mg concentration must not exceed 5,000 mg/L. Thus, claim 6 is indefinite. For the purposes of examination, this total concentration of Ca and Mg limitation will be interpreted as “100-5000 mg/L” per page 6 penultimate paragraph of the instant specification.
Claim 7 is indefinite due to the terms “during use”, “when stirring” and “a required concentration” disclosed in (2) of the claim. It is unclear what qualifies as “use” of the proposed nanofluid or what satisfies a “required concentration” for preparing such a nanofluid. The phrase “when stirring” is unclear as no stirring step is mentioned or introduced from step (1) in claim 7 when preparing the mother solution. Thus, claim 7 is indefinite. For the purposes of examination, “when stirring” will be interpreted as “while stirring”. For the purposes of examination, a “required concentration” will be interpreted as the totality of concentrations of claim 5, on which claim 7 depends, and “during use” will be broadly interpreted as any implementation or preparation of the core-shell nanoparticles in such a solution.
Claim 8 is indefinite as being a use claim with a process step by which the imbibition displacement is performed. Claims 9-10 are rejected as being dependent on, and failing to cure the deficiencies of, rejected claim 8.
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 1-10 are rejected under 35 U.S.C. 103 as being unpatentable over Zhong et al (CN115991982A) in view of Long et al (CN110373171A) and Li et al (NPL "A green deep eutectic solvent modified magnetic titanium dioxide nanoparticles for the solid-phase extraction of chymotrypsin").
Regarding claim 1, Zhong discloses an “ultra-small size active nanofluid” as well as its preparation and application thereof. Zhong discloses use of the nanofluid in low permeability reservoir oil displacement at temperatures between 60-120°C (thus, temperature tolerant) and in presence of salt ions such as K+, Na+, Mg2+, Ca2+, and Cl-, as well as a mineralization (or salinity) degree of water (thus salinity tolerant and contained in water). Zhong’s nanofluid contains an active nano silicon dot, SiO2, in a concentration of 0.05-0.2 wt% (or 0.1 wt% specifically). Zhong does not specify magnetic core-shell structured nanoparticles Fe3O4@TiO2. In an analogous invention, Long et al disclose a magnetic nanoparticle stable emulsion similarly capable of oil-water separation. Long creates a magnetic nanofluid containing magnetic core-shell nanoparticles Fe3O4@SiO2 but does not disclose TiO2 shell structure. Nonetheless, it would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to substitute the nanoparticle of Zhong for the nanoparticle of Long as a known nanoparticle alternative for making a temperature and salinity tolerant magnetic nanofluid for use in oil-water separation. Analogously, Li et al disclose a magnetic core-shell nanoparticle (Fe3O4@TiO2) for use in solid-phase extractions. Li discloses that Fe3O4 is a commonly selected magnetic carrier for use in extraction and separation due to its low toxicity, simple preparation, and superparamagnetic properties. Furthermore, Li teaches that TiO2 can be utilized as an oxide layer due to having high polarity, good hydrophilicity, and its stability with good dispersibility (introduction). Li discloses that shelling Fe3O4 with TiO2 effectively improves dispersibility of the nanoparticles and the larger specific surface area of TiO2 provides more reaction sites, thus improving extraction capabilities. It would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to substitute the SiO2 shell for TiO2, as informed by Li, as a known alternative Fe3O4 shelling material to improve dispersibility of the generated nanoparticles and subsequently implement to the temperature and salinity tolerant magnetic nanofluid of Zhong. Thus, Zhong, Long, and Li teach the claimed “A temperature and salinity tolerant magnetic nanofluid, comprising: magnetic core-shell structured nanoparticles Fe3O4@TiO2, with a content of 0.01-0.2 wt%, and water.”.
Regarding claim 2, Zhong, Long, and Li teach the magnetic nanofluid of claim 1. Furthermore, Zhong teaches a wt% of the included nanoparticle in nanofluid of 0.1%. Therefore, Zhong, Long, and Li teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 1, wherein the content of the magnetic core-shell structured nanoparticles Fe3O4@TiO2 is 0.1 wt%”.
Regarding claim 3, Zhong, Long, and Li teach the magnetic nanofluid of claim 1. Zhong is silent on preparation of core-shell nanoparticles. Long teaches a preparation method for their Fe3O4@SiO2 nanoparticles but differs in certain steps from the claimed invention. Li teaches a preparation method that matches the invention as claimed (Section 2.2.1). Li dissolves the Fe3O4 nanoparticles into ethanol and subsequently sonicates. Li then “slowly adds” aqueous solutions of TBOT (tetrabutyl titanate) and ammonia. Furthermore, Li mechanically stirs the solution for 5 h. Li does not specify mechanical stirring at “ambient temperature” nor “ultrasonic treatment until even dispersion”. However, it is well understood in the art, that a sonication step would be utilized to evenly disperse the solution for homogeneity. Further, Long does teach ultrasonically mixing to form a mixed solution. It would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to substitute sonication for ultrasonication as a known alternative mixing process to create core-shelled nanoparticles. Additionally, since Li does not specify a temperature of stirring, it can be assumed that said step occurs at ambient or room temperature. Li subsequently places the products at 25°C for 20 h, separates by an external magnet, washes with ultrapure water, and dries at 55°C in vacuum to obtain the core-shelled Fe3O4@TiO2 nanoparticles. It would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to prepare the core-shelled structured nanoparticles according to a known published method, as informed by Li, for synthesizing such magnetic nanoparticles to be used in the nanofluid. Thus, Zhong, Long, and Li teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 1, wherein a preparation method of the magnetic core-shell structured nanoparticles Fe3O4@TiO2 comprising: (1) dissolving nano Fe3O4 in ethanol, giving ultrasonic treatment until even dispersion, thereafter, adding slowly tetrabutyl titanate and ammonia solution, mechanical stirring for 5 h in ambient temperature; and (2) placing reaction products at 25 °C for 20 h, separating by using magnet, washing by using ultrapure water, vacuum drying at 55 °C and obtaining the magnetic core-shell structured nanoparticles Fe3O4@TiO2”.
Regarding claim 4, Zhong, Long, and Li teach the magnetic nanofluid of claim 3. Zhong discloses that low permeability reservoir matrix pore throats are 50-900nm, thus requiring nano-sized particles in the nanofluid. Zhong describes the ultra-small size of their silicon dot to be 3-5nm, thus an obvious starting point for implementation of core-shelled nanoparticles. Therefore, Zhong, Long, and Li teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 3, wherein the magnetic core-shell structured nanoparticles Fe3O4@TiO2 have particle sizes less than 20 nm”.
Regarding claim 5, Zhong, Long, and Li teach the magnetic nanofluid of claim 4. Zhong teaches that the water solution contains K+, Na+, Mg2+, Ca2+, and Cl-. The total concentration of K+ and Na+ are 1000-30000mg/L (thus does not exceed 40000mg/L). The total concentration of Ca2+ and Mg2+ are 100-2000mg/L (thus does not exceed 5000mg/L). The total mineralization degree (understood to be salinity) is 2000-60000mg/L (thus does not exceed 90000mg/L). Therefore, Zhong, Long, and Li teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 4, wherein the water in the temperature and salinity tolerant nanofluid comprises water containing K+, Na+, Mg2+, Ca2+ and Cl-, wherein a total concentration of K+ and Na+ does not exceed 40000 mg/L, a total concentration of Ca2+ and Mg2+ does not exceed 5000 mg/L, and a salinity of the water does not go beyond 90000 mg/L”.
Regarding claim 6, Zhong, Long, and Li teach the magnetic nanofluid of claim 5. Zhong teaches that the water solution contains K+, Na+, Mg2+, Ca2+, and Cl-. The total concentration of K+ and Na+ are 1000-30000mg/L (falls within 1000-40000mg/L). The total concentration of Ca2+ and Mg2+ are 100-2000mg/L (falls within 100-5000mg/L). The total mineralization degree (understood to be salinity) is 2000-60000mg/L (falls within 2000-90000mg/L). Zhong does not mention aggregations within the nanofluid above a salinity content. However, aggregations forming, or precipitants, would be expected as the water becomes more concentrated with ions, a byproduct of increased salinity, as the water is less capable of dispersing the nanoparticles within the nanofluid. Aggregations or precipitation out of solution would be inherent to the nanoparticles and nanofluid, thus arrival to the invention as claimed would inherently possess such a quality. Regardless, both Long and Li speak on the ability of their shelled nanoparticles to maintain good dispersibility and reduce aggregations in solution, particularly under high temperature and high salt condition according to Long. Thus, it would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to ensure this lack of aggregation property extends to the prepared nanofluid as preventing automatic aggregation of droplets enables a stable emulsion, as informed by Long. Therefore, Zhong, Long, and Li teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 5, wherein the water in the temperature and salinity tolerant nanofluid comprises water containing K+, Na+, Mg2+, Ca2+ and Cl-, wherein a total concentration of K+ and Na+ is 1000-40000 mg/L, a total concentration of Ca2+ and Mg2+, and a total salinity of the water is 2000-90000 mg/L, and when the salinity of the water goes beyond this range, aggregations in the magnetic nanofluid will increase”.
Regarding claim 7, Zhong, Long, and Li teach the nanofluid of claim 5. Zhong teaches dissolving the nanoparticles into water which prepares a “mother liquid” (or mother solution) for “further use”. Further, Zhong continues adding water to the “mother liquid” under “the condition of stirring” and “diluting to the concentration”. In the embodiments, Zhong further describes that the water contains the necessary ions of K+, Na+, Mg2+, Ca2+ and Cl- within the disclosed concentration ranges. Thus, Zhong, Long, and Li teach the claimed “A preparation method of the temperature and salinity tolerant magnetic nanofluid according to claim 5, wherein the preparation method comprises: (1) adding the magnetic core-shell structured nanoparticles Fe3O4@TiO2 to water to be mother solution; and (2) during use, adding water to dilute the mother solution when stirring, and obtaining the temperature and salinity magnetic nanofluid with a required concentration”.
Regarding claim 8, Zhong, Long, and Li teach the nanofluid of claim 1. Further, Zhong describes the prepared nanofluid is to be used in ultra-low permeability reservoir as an oil displacement agent. Imbibition displacement is understood in the art to displace oil or gas from the matrix of rock or soil pores, thus Zhong teaches imbibition displacement. Therefore, Zhong, Long, and Li teach the claimed “Use of the temperature and salinity tolerant magnetic nanofluid according to any of claim 1 in imbibition displacement of ultra-low permeability reservoirs”.
Regarding claim 9, Zhong, Long, and Li teach the use of the nanofluid according to claim 8. Zhong further discloses that the reservoir temperature is 60-120°C, thus falling within the claimed range of 20-120°C. Therefore, Zhong, Long, and Li teach the claimed “The use of the temperature and salinity tolerant magnetic nanofluid according to claim 8, wherein strata conditions of the ultra-low permeability reservoirs comprise temperature at 20-120 °C”.
Regarding claim 10, Zhong, Long, and Li teach the use of the nanofluid according to claim 8. Zhong does not disclose a specific salinity of the strata outside of “high salinity reservoir”. Zhong’s nanofluid (which is specific to SiO2) is capable of withstanding salinity or mineralization between 2000-60000 mg/L as described above in rejection of claims 5-6, thus it would be expected to be suitable for use in such strata conditions whereby salinity is 0-90000 mg/L. Further, Long discloses their core-shell nanoparticle is capable of withstanding “high salt” as well. Regardless, such stability is an inherent property of the nanoparticles or corresponding nanofluid, thus by arrival to the magnetic nanofluid as claimed, the corresponding solution would be expected to be capable to operate in such strata conditions. Thus, Zhong, Long, and Li teach the claimed “The use of the temperature and salinity tolerant magnetic nanofluid according to claim 8, wherein strata conditions of the ultra-low permeability reservoirs comprise salinity at 0-90000 mg/L”.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Zhong et al in view of Long et al and Li et al as applied to claim 3 above, and further in view of Marín et al (Ultrasonic dispersion of nanostructured materials with probe sonication − practical aspects of sample preparation, Powder Technology, Volume 318, 2017, Pages 451-458, ISSN 0032-5910, https://doi.org/10.1016/j.powtec.2017.05.049).
Zhong, Long, and Li teach the magnetic nanofluid of claim 3. Zhong discloses that low permeability reservoir matrix pore throats are 50-900nm, thus requiring nano-sized particles in the nanofluid. Zhong describes the ultra-small size of their silicon dot to be 3-5nm, thus an obvious starting point for implementation of core-shelled nanoparticles. However, Long teaches a Fe3O4 nanoparticle of 20nm or greater and Li a core-shell nanoparticle having diameters around 300nm (Section 3.1). Li does teach a preparation method for such core-shell nanoparticles involving sonication steps as described in the rejection of claim 3 above. Marín teaches ultrasonication as a technique to disperse synthesized precipitated nanoparticles (results section), which can be broadly applied to nanomaterials or nanoparticles as disclosed in the introduction. Marín utilizes ultrasonication to disintegrate submicron aggregates, fragment or erode agglomerates/aggregates, and achieve a maximum dispersion into smallest dispersible units (i.e., a particle size).Thus, it would have been prima facie obvious to one of ordinary skill in the art, as of the effective filing date, to modify the sonication step in the method of Li, as informed by Marín, such that ultrasonication is applied to improve dispersion and break up particles into smaller units to achieve a smaller particle size closer to that informed by Zhong and subsequently implemented to the magnetic nanofluid. Therefore, Zhong, Long, Li, and Marín teach the claimed “The temperature and salinity tolerant magnetic nanofluid according to claim 3, wherein the magnetic core-shell structured nanoparticles Fe3O4@TiO2 have particle sizes less than 20 nm”.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Mousavi et al and Song et al disclose relevant preparation methods of core-shell Fe3O4@TiO2 nanoparticles. Recio et al (US PGPub 20230115715) disclose relevant fluid compositions for treating wellbores. Ayirala et al (US PGPub 20200172794) disclose relevant oil recovery compositions with metal oxide nanoparticles. Jaing et al (CN114774096A) disclose relevant uses of such compositions in ultra-low permeability reservoirs.
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/NWFG/Examiner, Art Unit 1759
/MELVIN C. MAYES/Supervisory Patent Examiner, Art Unit 1759
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