# US 12,180,418 B1 · Water-based drilling fluid formulated using MnZnFe-layered triple hydroxide and a process for scavenging hydrogen sulfide from subterranean geological formations > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,418 B1 - Document ID: US12180418B1 - Status: Granted - Kind: B1 - Application number: 18/810,299 - Filed: 2024-08-20 - Granted: 2024-12-31 - Earliest claimed: 2024-08-20 - Assignees: King Fahd University of Petroleum and Minerals - Applicants: King Fahd University of Petroleum and Minerals - Inventors: Sagheer A. Onaizi; Mustapha Iddrisu - Web page: https://patentgrep.com/patent/US12180418B1 ## CPC - C09K 8/528: inorganic depositions, e.g. sulfates or carbonates - C09K 2208/20: Hydrogen sulfide elimination - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract A method of removing hydrogen sulfide from a subterranean geological formation includes injecting a drilling fluid suspension in the subterranean geological formation. The drilling fluid suspension has a pH of 10 or more and includes a layered triple hydroxide material, including manganese, zinc, and iron, in an amount of 0.01 to 0.5 percent by weight of the drilling fluid suspension. The method further includes circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the layered triple hydroxide material in the water-based mud. ## Claims ### Claim 1 A method of removing hydrogen sulfide from a subterranean geological formation, comprising: injecting a drilling fluid suspension in the subterranean geological formation, wherein the drilling fluid suspension comprises a layered triple hydroxide material comprising manganese, zinc, and iron, wherein the drilling fluid suspension has a pH of 10 or more, wherein the layered triple hydroxide material is present in an amount of 0.01 to 0.5 percent by weight of the drilling fluid suspension, circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud; and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the layered triple hydroxide material in the water-based mud. ### Claim 2 (depends on 1) The method of claim 1, wherein a molar ratio of manganese to zinc to iron is 1-3:0.5-2:0.5-2 in the layered triple hydroxide material. ### Claim 3 (depends on 1) The method of claim 1, wherein a molar ratio of manganese to zinc to iron is 2:1:1 in the layered triple hydroxide material. ### Claim 4 (depends on 1) The method of claim 1, wherein the layered triple hydroxide material has a breakthrough capacity of 110 to 150 mg of hydrogen sulfide per gram of the layered triple hydroxide. ### Claim 5 (depends on 1) The method of claim 1, wherein the layered triple hydroxide material has a saturation capacity of 230 to 270 mg of hydrogen sulfide per gram of the layered triple hydroxide. ### Claim 6 (depends on 1) The method of claim 1, wherein the drilling fluid suspension further comprises a bentonite, a polysaccharide, a starch, a hydroxide, and a carbonate. ### Claim 7 (depends on 1) The method of claim 1, wherein a breakthrough time for the hydrogen sulfide in the presence of the drilling fluid suspension is 5 to 10 times greater compared to a breakthrough time for the hydrogen sulfide in the presence of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 8 (depends on 1) The method of claim 1, wherein a saturation time for the hydrogen sulfide in the presence of the drilling fluid suspension is 1 to 4 times greater compared to a saturation time for the hydrogen sulfide in the presence of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 9 (depends on 1) The method of claim 1, wherein a breakthrough capacity for the hydrogen sulfide in the presence of the drilling fluid suspension is 5 to 10 times greater compared to a breakthrough capacity for the hydrogen sulfide in the presence of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 10 (depends on 1) The method of claim 1, wherein a saturation capacity for the hydrogen sulfide in the presence of the drilling fluid suspension is 1 to 3 times greater compared to a saturation capacity for the hydrogen sulfide in the presence of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 11 (depends on 1) The method of claim 1, wherein a plastic viscosity of the drilling fluid suspension is 0.8 to 1.2 times greater compared to a plastic viscosity of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 12 (depends on 1) The method of claim 1, wherein an apparent viscosity of the drilling fluid suspension is 0.8 to 1.2 times greater compared to an apparent viscosity of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 13 (depends on 1) The method of claim 1, wherein a yield point of the drilling fluid suspension is 0.9 to 1.2 times greater compared to a yield point of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 14 (depends on 1) The method of claim 1, wherein a carrying capacity of the drilling fluid suspension is 0.9 to 1.2 times greater compared to a carrying capacity of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 15 (depends on 1) The method of claim 1, wherein a fluid loss of the drilling fluid suspension is 0.9 to 1.2 times greater compared to a fluid loss of the drilling fluid suspension without the layered triple hydroxide material. ### Claim 16 (depends on 1) The method of claim 1, wherein the scavenging hydrogen sulfide converts the hydrogen sulfide into an elemental sulfur and an insoluble sulfide. ### Claim 17 (depends on 1) The method of claim 1, wherein a gel strength of the drilling fluid suspension at a time of 10 seconds is 0.9 to 1.3 times greater compared to a gel strength of the drilling fluid suspension without the layered triple hydroxide material at a time of 10 seconds. ### Claim 18 (depends on 1) The method of claim 1, wherein a gel strength of the drilling fluid suspension at a time of 10 minutes is 0.9 to 1.3 times greater compared to a gel strength of the drilling fluid suspension without the layered triple hydroxide material at a time of 10 minutes. ### Claim 19 (depends on 1) The method of claim 1, wherein the layered triple hydroxide material is made by a process, comprising: dissolving a manganese salt, a zinc salt, and an iron salt in water to form a metallic solution; dissolving a base and a carbonate salt to form an alkali solution; adding dropwise the metallic solution and the alkali solution to water and stirring to form a first solution; stirring the first solution for 20 to 40 minutes to form a product; hydrothermally treating the product at a temperature from 120 to 180° C. for a time of 12 to 36 hours to form the layered triple hydroxide material; and drying the layered triple hydroxide material at a temperature of 60 to 100° C. ### Claim 20 (depends on 1) The method of claim 1, wherein the drilling fluid suspension has a density of 2 to 20 parts per gram (ppg).