# US 11,898,097 B2 · Modified acid compositions as alternatives to conventional acids in the oil and gas industry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,097 B2 - Document ID: US11898097B2 - Status: Granted - Kind: B2 - Application number: 17/195,084 - Filed: 2021-03-08 - Published: 2021-07-01 - Granted: 2024-02-13 - Earliest claimed: 2017-12-22 - Assignees: Dorf Ketal Chemicals Fze - Applicants: Fluid Energy Group Ltd. - Inventors: Clay Purdy; Markus Weissenberger - Web page: https://patentgrep.com/patent/US11898097B2 ## CPC - C09K 8/74: combined with additives added for specific purposes - C23F 14/02: by chemical means - C09K 8/528: inorganic depositions, e.g. sulfates or carbonates - C23F 11/04: in markedly acid liquids - E21B 43/27: by use of eroding chemicals, e.g. acids - C09K 2208/32: Anticorrosion additives - E21B 37/06: using chemical means for preventing or limiting {, e.g. eliminating,} the deposition of paraffins or like substances - E21B 43/26: by forming crevices or fractures - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - C23F: NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE (working metal by laser beams B23K26/00; desurfacing by applying flames B23K7/00; working of metal by electro-erosion B23H; producing decorative effects by removing surface material, e.g. by engraving, by etching, B44C1/22; electrolytic etching or polishing C25F); INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25 - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract An aqueous modified acid composition for use in oil industry activities, said composition comprising: an amino acid, an alkanolamine and strong acid wherein the mineral acid: alkanolamine/amino acid are present in a molar ratio of not more than 15:1, preferably not more than 10:1; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids. ## Claims ### Claim 1 An aqueous modified acid composition comprising: HCl; an amino acid; and an alkanolamine; wherein the mineral acid: alkanolamine/amino acid are present in a molar ratio of not more than 15:1; wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof; and wherein the aqueous modified acid composition has a pH of less than 1. ### Claim 2 (depends on 1) An aqueous modified acid composition according to claim 1, wherein the amino acid: alkanolamine proportion ranges from 1%: 99% to 99%: 1%. ### Claim 3 (depends on 1) An aqueous modified acid composition according to claim 1, wherein the amino acid: alkanolamine proportion ranges from 20%: 80% to 80%: 20%. ### Claim 4 (depends on 1) An aqueous modified acid composition according to claim 1, wherein the amino acid: alkanolamine proportion ranges from 30%: 70% to 70%: 30%. ### Claim 5 (depends on 1) An aqueous modified acid composition according to claim 1, wherein the amino acid: alkanolamine proportion is 50%: 50%. ### Claim 6 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 10:1. ### Claim 7 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 7.0:1. ### Claim 8 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 4:1. ### Claim 9 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 3:1. ### Claim 10 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio ranging from 3:1 to 12:1. ### Claim 11 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the HCl: alkanolamine/amino acid are present in a molar ratio ranging from 5:1 to 10:1. ### Claim 12 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the alkanolamine is selected from the group consisting of: monoethanolamine; diethanolamine; triethanolamine and combinations thereof. ### Claim 13 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the alkanolamine is monoethanolamine. ### Claim 14 (depends on 1) The aqueous modified acid composition according to claim 1, wherein the alkanolamine is diethanolamine. ### Claim 15 (depends on 1) The aqueous modified acid composition according to claim 1, further comprising a metal iodide or iodate selected from the group consisting of: cuprous iodide; potassium iodide; sodium iodide; lithium iodide and combinations thereof. ### Claim 16 (depends on 1) The aqueous modified acid composition according to claim 1, further comprising an alkynyl alcohol or derivative thereof present in a concentration ranging from 0.01 to 5% w/w. ### Claim 17 (depends on 16) The aqueous modified acid composition according to claim 16, wherein the alkynyl alcohol or derivative thereof is propargyl alcohol or a derivative thereof. ### Claim 18 (depends on 15) The aqueous modified acid composition according to claim 15, wherein the metal iodide is present in a concentration ranging from 0.1 to 2% by weight of the total weight of the composition. ### Claim 19 The use of an aqueous modified acid composition in an oil industry activity, said composition comprising: HCl; an amino acid; and an alkanolamine; wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 15:1, wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof; wherein the aqueous modified acid composition has a pH of less than 1; and wherein the use comprises an activity selected from the group consisting of: stimulate formations; assist in reducing breakdown pressures during downhole pumping operations; treat wellbore filter cake post drilling operations; assist in freeing stuck pipe; descale pipelines and/or production wells; increase injectivity of injection wells; lower the pH of a fluid; remove undesirable scale on a surface selected from the group consisting of: equipment, wells and related equipment and facilities; fracture wells; complete matrix stimulations; conduct annular and bullhead squeezes & soaks; pickle tubing, pipe and/or coiled tubing; increase effective permeability of formations; reduce or remove wellbore damage; clean perforations; and solubilize limestone, dolomite, calcite and combinations thereof. ### Claim 20 A method of treating a metal surface with a composition comprising: HCl; an amino acid; and an alkanolamine; wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 15:1, wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof; wherein the composition has a pH of less than 1; said method comprising the steps of: providing said composition; exposing said metal surface to said composition; allowing said composition a sufficient period of time to act upon said surface; and optionally, removing the acid composition when the exposure time has been determined to be sufficient for the operation to be complete or sufficiently complete.