# US 11,906,503 B2 · Isotopocule analysis of hydrocarbon contamination > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,503 B2 - Document ID: US11906503B2 - Status: Granted - Kind: B2 - Application number: 17/304,974 - Filed: 2021-06-29 - Published: 2022-01-06 - Granted: 2024-02-20 - Earliest claimed: 2020-07-02 - Assignees: ExxonMobil Technology and Engineering Company - Applicants: ExxonMobil Technology and Engineering Company - Inventors: David T. Wang; Muhammad Asif; Michael J. Formolo - Web page: https://patentgrep.com/patent/US11906503B2 ## CPC - G01N 33/2835: {Specific substances contained in the oils or fuels} - B01D 15/08: Selective adsorption, e.g. chromatography - G01N 21/39: using tunable lasers - G01N 27/62: by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract Methods for identifying hydrocarbon contamination sources may include fingerprinting hydrocarbons using isotopocule analyses for BTEX compounds. For example, methods for identifying hydrocarbon contamination sources may comprise: extracting BTEX compounds from a sample; measuring the isotopocule composition of the BTEX compounds; and determining a characteristic of the sample based on the isotopocule composition. Such characteristics may include, but are not limited to, the characteristic of the sample comprises one or more selected from the group consisting of: a source of the sample, a condition at which the sample formed or was last equilibrated, a migration time from a source to a sample location, weathering of the sample, and degree to which the sample is anthropogenic and naturally-occurring. ## Claims ### Claim 1 A method comprising: extracting BTEX compounds from a sample; measuring an isotopocule composition of the BTEX compounds; and determining a characteristic of the sample based on the measured isotopocule composition, wherein the characteristic of the sample comprises a weathering of the sample, wherein the weathering of the sample is a chemical weathering of the sample or a biological weathering of the sample, wherein an amount of the chemical weathering is estimated based on an identified change in an amount of hydroxide (—OH) in the sample, or wherein an amount of the biological weathering is estimated based on an identified change in location and quantity 13C-13C of bonds in the sample. ### Claim 2 (depends on 1) The method of claim 1, wherein the sample comprises water, petroleum, petrochemicals, and/or solid material. ### Claim 3 (depends on 1) The method of claim 1, wherein the extracting of the BTEX compounds uses preparative capillary gas chromatography. ### Claim 4 (depends on 1) The method of claim 1, wherein the measuring of the isotopocule composition uses high-resolution mass spectrometry. ### Claim 5 (depends on 1) The method of claim 1, wherein the measuring of the isotopocule composition uses tunable laser infrared spectroscopy. ### Claim 6 (depends on 1) The method of claim 1, wherein the characteristic of the sample further comprises a differentiation of a plurality of sources. ### Claim 7 (depends on 6) The method of claim 6, wherein the differentiation comprises (a) inverse numerical methods and/or (b) minimization of errors in observed data compared to results simulated by forward modeling methods. ### Claim 8 (depends on 1) The method of claim 1, further comprising: hydrocarbon fingerprinting the sample, wherein the hydrocarbon fingerprinting is selected from the group consisting of: a distribution of specific hydrocarbons in the sample, a ratio of specific hydrocarbons in the sample, a ratio of carbon isotopes in the sample, an absence or presence of biomarkers in the sample, and any combination thereof. ### Claim 9 (depends on 8) The method of claim 8, wherein the hydrocarbon fingerprinting involves one selected from the group consisting of: gas chromatography, liquid chromatography, nuclear magnetic resonance spectroscopy, infrared spectroscopy, Raman spectrometry, and any combination thereof. ### Claim 10 (depends on 1) The method of claim 1, wherein the weathering of the sample is the chemical weathering of the sample. ### Claim 11 (depends on 1) The method of claim 1, wherein the weathering of the sample is the biological weathering of the sample. ### Claim 12 (depends on 1) The method of claim 1, further comprising: identifying a source of the sample by comparing the measured isotopocule composition with a database comprising isotopocule compositions of BTEX compounds from a variety of sources or a suspected source. ### Claim 13 A method comprising: extracting BTEX compounds according to Compound 1 from a sample where R1-R6 are independently hydrogen, methyl, ethyl, n-propyl, iso-propyl, hydroxyl, carboxyl, acyl, amino, nitro, sulfo, fluoro, chloro, bromo, or iodo; measuring an isotopocule composition of the BTEX compounds; and determining a characteristic of the sample based on the measured isotopocule composition, wherein the characteristic of the sample comprises a weathering of the sample, wherein the weathering of the sample is a chemical weathering of the sample or a biological weathering of the sample, wherein an amount of the chemical weathering is estimated based on an identified change in an amount of hydroxide (—OH) in the sample, or wherein an amount of the biological weathering is estimated based on an identified change in location and quantity of 13C-13C bonds in the sample. ### Claim 14 (depends on 13) The method of claim 13, wherein the sample composes water, petroleum, petrochemicals, and/or solid material. ### Claim 15 (depends on 13) The method of claim 13, wherein the extracting of the BTEX compounds uses preparative capillary gas chromatography. ### Claim 16 (depends on 13) The method of claim 13, wherein the measuring of the isotopocule composition uses high-resolution mass spectrometry. ### Claim 17 (depends on 13) The method of claim 13, wherein the measuring of the isotopocule composition uses tunable laser infrared spectroscopy. ### Claim 18 (depends on 13) The method of claim 13, wherein the characteristic of the sample further comprises a differentiation of a plurality of sources. ### Claim 19 (depends on 18) The method of claim 18, wherein the differentiation comprises (a) inverse numerical methods and/or (b) minimization of errors in observed data compared to results simulated by forward modeling methods. ### Claim 20 (depends on 13) The method of claim 13, further comprising: hydrocarbon fingerprinting the sample, wherein the hydrocarbon fingerprinting is selected from the group consisting of: a distribution of specific hydrocarbons in the sample, a ratio of specific hydrocarbons in the sample, a ratio of carbon isotopes in the sample, an absence or presence of biomarkers in the sample, and any combination thereof. ### Claim 21 (depends on 13) The method of claim 13, wherein the weathering of the sample is the chemical weathering of the sample. ### Claim 22 (depends on 13) The method of claim 13, wherein the weathering of the sample is the biological weathering of the sample.