Ea1112

The Brunauer–Emmett–Teller technique (3Flex, Micrometrics, Norcross, GA, USA) was used to measure the specific surface area of each sorbent with N₂ adsorption isotherms. X-ray diffraction (XRD; D8 Discover, Bruker, Billerica, MA, USA) measurements were used to identify the crystalline and non-crystalline properties of each sorbent. To analyze the surface structure and microphotography of each sorbent, field emission scanning electron microscopy (Merlin compact, Zeiss, Oberkochen, Germany) measurements were performed. An X-ray photoelectron spectroscopy (XPS) analysis was conducted with a spectrophotometer (K-Alpha+, Thermo Fisher Scientific, Waltham, MA, USA) using an Al Kα source (1486.6 eV of photons).
For the chemical analysis, pH and electric conductivity (EC) were measured using a pH meter (MP220, Mettler Toledo, Worthington, OH, USA) and an EC meter (S230, Mettler Toledo), respectively, after mixing each sorbent with deionized water at a 1:5 (w/v) ratio for 1 h. The total nitrogen and total carbon were measured using an elemental analyzer (EA1112, Thermo Fisher Scientific). The temperature in the EA reactor was set to 1000 °C, and the flow rate of the carrier gas (He, O₂, and air) was maintained at 0.12 L/min.

The shape and microstructure of the waste soot was observed by transmission electron microscopy (TEM, JEM-2100F, JEOL, Akishima, Tokyo, Japan) at an accelerating voltage of 200 kV. The specific surface area of soot was determined from the N₂ adsorption-desorption isotherms obtained using a Quantachrome sorption analyzer (Autosorb-1, Boynton Beach, FL, USA) by the Brunauer–Emmett–Teller (BET) method. Before the N₂ adsorption-desorption experiments, all samples were heated under N₂ at 200 °C for 2 h to remove moisture. Thermogravimetric analysis (TGA) was performed using a TGA Q500 device (TA Instrument, New Castle, DE, USA) to analyze the weight of the soot residue. To obtain the elemental composition, a carbon-hydrogen-nitrogen-sulfur (CHNS) analyzer (Thermo Fisher Scientific, EA1112, Waltham, MA, USA) was used.

The portions of rock cores examined as described above were powdered using a mortar and pestle. Clay-sized fractions in powdered samples were suspended in distilled and deionised water, centrifuged at 3000 rpm for 5 min, and then the supernatant was collected. Next, the clay fraction was collected from the supernatant by centrifugation at 10,000 rpm for 10 min and dried at 50 °C and then subjected to organic carbon characterizations. KBr pellets made of the clay fractions were analyzed with Fourier transformed infrared-ray (FT-IR) spectrometry (Perkin Elmer Spectrum 2000, Tokyo, Japan) to clarify lipids in extant microorganisms. The pellets in the specimen chamber filled by N₂ gas were analyzed by infrared rays through KBr beam-splitter with the MCT detector. Representatvive FT-IR spectra were obtained by averaging 100 individual spectra. The contents of organic carbon in the clay fractions were measured using a mass spectrometer (Thermo Electron DELTAplus Advantage; Thermo Fisher Scientific Inc., Waltham, MA) connected to an elemental analyzer (EA1112, Thermo Electron DELTAplus Advantage) through a Conflo III interface. The clay fractions were heated at 100 °C in 3% HCl to eliminate carbonate minerals, washed twice with distilled, deionized water, and dried.

The powdered core sample was suspended in sterilized deionized water. The supernatant after centrifugation at 3,000 rpm for 5 min contained the clay fraction. The clay fraction was collected by centrifugation at 10,000 rpm for 10 min. We measured the organic carbon contents of the powdered core sample and the clay fraction using a mass spectrometer (Thermo Electron DELTAplus Advantage; Thermo Fisher Scientific Inc., Waltham, MA) connected to an elemental analyzer (EA1112, Thermo Electron DELTAplus Advantage) through a Conflo III interface. Before the measurement, the sample was heated at 100°C in 3% HCl to eliminate carbonate minerals, washed twice with distilled, deionized water, and dried.

Melting points were determined on a Büchi melting point B-540 apparatus (BÜCHI Labortechnik AG, Flawil, Switzerland) and are uncorrected. Element analyses were performed on a Thermo Finnigan EA1112 (San Jose, CA, USA) at the spectropole of the Aix-Marseille University. Both ¹H- and ¹³C-NMR spectra were determined on a Bruker Avance 250 spectrometer (Wissembourg, France) at the Service de RMN de la Faculté de Pharmacie de Marseille of the Aix-Marseille University and on a Bruker Avance III NanoBay 300 MHz spectrometer at the spectropole of Aix-Marseille University. The ¹H- and the ¹³C-chemical shifts are reported from CDCl₃ peaks: ¹H (7.26 ppm) and ¹³C (77 ppm) or Me₂SO-d6 (39.6 ppm). Multiplicities are represented by the following notations: s, singlet; d, doublet; t, triplet; q, quartet; m, a more complex multiplet, or overlapping multiplets. The following adsorbents were used for column chromatography: silica gel 60 (Merck, particle size 0.063–0.200 mm, 70–230 mesh ASTM, (Merck, Darmstadt, Germany). Thin Layer Chromatography (TLC) was performed on 5 cm × 10 cm aluminum plates coated with silica gel 60 F254 (Merck) in an appropriate solvent.

600 samples were desalinated and powdered prior to compositional measurements. Total Inorganic Carbon (TIC) was determined by carbon coulometer (UIC-CM5130). The accuracy of TIC content of standard reference material (Ultrapure CaCO₃ from Sigma-Aldrich) was 12.0 ± 0.25 wt%. Total carbon (TC) content was measured by the elemental analyzer (Thermo EA1112). Total organic Carbon (TOC) content was calculated by subtracting TIC from TC. 2, 4-DNP was used as a calibration standard for TC. Reproducibility for TC in NIST-SRM1944 sediment standard was found to be 4.4 ± 0.2 wt%. Carbon isotope measurement of total organic carbon (δ¹³C_TOC) was carried out on decarbonated sediments. A Thermo-Finnegan Delta-V-Plus continuous flow isotope ratio mass spectrometer coupled to an elemental analyzer (Thermo EA1112) was used for C isotope ratio measurements. The external standard reproducibility calculated for δ¹³C_TOC using IAEA-C3 cellulose standard was −24.7 ± 0.1‰ (VPDB). The results are presented in Supplementary Table 2.