SINGLE-PHASE RETARDED ACID BASED ON AN AMPHOTERIC SURFACTANT

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 Applicant’s claim of priority as a 35 U.S.C. §371 national stage entry of PCT/US2023/016026 filed March 23, 2023, which claims priority to U.S. provisional application 63/269,803 filed March 23, 2022, is hereby acknowledged. 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 1-18 are rejected under 35 U.S.C. §102(a)(1) as anticipated by Xu (US 2016/0280986 A1 to Xu, published Sept. 29, 2016). Xu discloses an acidic treatment fluid, and a method of treating a subterranean formation by injecting the treatment fluid, wherein the treatment fluid comprises a weakly emulsifying surfactant, an aqueous fluid and an acid, wherein other additives suitable for use in a particular wellbore application can be included in the treatment fluid (abstract; [0015] to [0018]; [0028]; [0029]; [0035]; Figures 1-3; claims 19 and 20 of Xu). A preferred acid is hydrochloric acid and a preferred weakly-emulsifying surfactants include hydroxysultaines, such as lauryl hydroxysultaine (an alky sulfobetaine) ([0026]; [0029]; claims 6, 9, 13 and 16 of Xu). Xu discloses that weakly emulsifying surfactants useful in treating subterranean formation are capable of preventing and/or dispersing acid-induced sludge caused by the acidic treatment fluid, wherein in one sample, 4,000 weak surfactant (lauryl hydroxysultaine) was added to an aqueous composition comprising 15% HCl, and spent acid was formed by adding MgCl2 and CaCl2 to the15% HCL acid fluid, in which the pH was raised to 4.0 ([0022] to [0026]; [0047] to [0050]; [0053]; claims 12, 13 and 16 of Xu). Xu further discloses that the weakly-emulsifying surfactant can be present in the aqueous acidic fluid in an amount of 0.1 to 50 gallons per barrel per thousand gallons of acid/water ([0027]). Additives that can be added in combination with the acid include magnesium acetate ([0029]). The treatment fluid can further include salts, such as magnesium chloride, or other additives, such as fluid-loss additives, friction reducers and iron-control agents ([0033]; [0035]; [0042]; claim 20 of Xu). The Examples and claims 1-11 in Xu are drawn to experiments and a method of treating a subterranean formation using Xu’s treatment acidic aqueous treatment fluid. Thus, the instant claims are anticipated by Xu. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN J FIGUEROA whose telephone number is (571)272-8916. The examiner can normally be reached on 8:30 am -6:00 pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, JOSEPH DEL SOLE can be reached on 571-272-1130. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. 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. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /JOHN J FIGUEROA/Primary Examiner, Art Unit 1763 December 13, 2025