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[Display omitted] • ODS of model sulfur compounds and AXL was investigated over the PMoA/G5 catalyst. • The extraction efficiency for sulfone was compared between acetonitrile and methanol. • FT-ICR MS and NMR analyzed the detailed sulfone compound distribution. • Acetonitrile showed better selectivity for polyaromatic sulfone than methanol. PMoA/G5 catalyst was synthesized, and its oxidative desulfurization (ODS) performance on model oil was studied. The catalyst and oxidation-extraction-adsorption system was used for the ODS of Arabian Extra light oil (AXL). Acetonitrile and methanol were chosen as different extractants for the extraction of sulfones (O 2 S and O 2 S 4). The distribution of sulfone was first reported in detail at each of the three-stage extraction solvents at the molecular level analyzed by the Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), proton, and 13C nuclear magnetic resonance (1H NMR,13C NMR). The FT-ICR MS results show that the extracted proportion of macromolecular sulfone compounds increases with the extraction stages. Acetonitrile exhibited better selectivity than methanol for polyaromatic sulfone with a high carbon number for the O 2 S species with double bond equivalent (DBE) = 12–15 and O 2 S 2 species with DBE = 11–16. The NMR results reveal that polyaromatics with naphthenic rings and a low carbon number (<30) can be easily extracted due to their high polarity. The excellent performance of the PMoA/G5 catalyst makes it a promising candidate in the ODS reaction, and the research results give guidelines for ODS technology. [ABSTRACT FROM AUTHOR]

• Systematically compared ODS of model oil between mechanical stirring and sonication. • Activate energy (E a) for ODS of DBT under sonication is 8.92 kJ/mol. • The viscosity of AXL increased after oxidative desulfurization. • APPI FT-ICR characterized sulfur-containing compounds distribution. • A decrease in aromatic hydrocarbon content after ODS was evidenced by NMR. The oxidative desulfurization (ODS) of model oil (BT, DBT, and 4,6-DMDBT) was studied with Mo/Ti-TUD-1 catalyst under mechanical stirring and ultrasonic-assisted conditions. ODS of DBT followed the pseudo-first-order kinetic model under both conditions and achieved a maximum conversion of 99%. The use of ultrasound instead of mechanical stirring significantly shortens the reaction time from 80 to 15 min. The oxidative reactivity of sulfur compounds in the model oil followed the same order under the mechanical stirring and ultrasound: 4,6-DMDBT > DBT > BT. Then ultrasound-assisted oxidative desulfurization of Arabia extra light oil was performed at 60 °C. It removed 56.5% of sulfur from the Arabian extra light oil feedstock. APPI FT-ICR characterized the sulfur compounds distribution. The S 1 , S 2 , O 2 S 1 , and O 4 S 2 class species were identified in Arabian extra light oil feedstock, raffinate, and methanol extraction phase samples. The abundant O 2 S 1 class species which had 9–15 Double Bond Equivalent (DBE) values and 15–30 carbon numbers, O 4 S 2 class species with 11–20 DBE and 20 < carbon number < 40 were detected in the extraction phase. 1H NMR and 13C NMR results revealed that the molecular structure in Arabian extra light oil is aromatic-base with a high alkylation degree. Combined with the FT-ICR and NMR results, those sulfur-containing compounds with lower alkylation degrees were converted to sulfone over Mo/Ti-TUD-1 catalyst and extracted by methanol. [ABSTRACT FROM AUTHOR]

• Structural level characterization of different TPO distillate fractions is presented. • Sulfur species are mainly in the form of dibenzothiophene and benzonaphthothiophene. • Distillation allowed concentrating sulfur containing compounds in the heavy fraction. Tire pyrolysis oil (TPO) is a complex mixture of hydrocarbons spanning a wide boiling point range. Due to its complexity, direct implementation of TPO to combustion applications has been challenging. Distillation is a simple method for grouping similar compounds, based on their volatility, thereby facilitating further upgrading and use. In this work, TPO was distilled at atmospheric pressure into different fractions (light, low-middle, high-middle, and heavy), and the structural characteristics of each fraction were explored. Therefore, advanced analytical techniques such as GC–MS, APPI FT-ICR MS and 1H and 13C NMR were utilized. For the light fraction, the GC–MS revealed a significant presence of benzene, toluene, and xylene, as well as limonene. From the APPI FT-ICR MS results, the low-middle, high-middle, and heavy fractions were classified into a number of molecular classes. Among these, pure hydrocarbons (HC), hydrocarbons containing one sulfur atom (S 1), hydrocarbons containing two oxygen atoms (O 2), etc. Here, HC and S 1 were found to be the most abundant molecular classes in all fractions. Finally, a structural analysis of the functional groups present in each TPO fraction was conducted by 1H and 13C NMR. Average molecular parameters (AMPs), such as the number of aromatic, naphthenic, and olefinic carbons/hydrogens, were determined. In addition, derived AMPs, such as the aromaticity factor (fa), C/H paraffinic, C/H aromatic, etc., were calculated. Fractionation by distillation resulted in concentration of both the sulfur and aromatic compounds in the heaviest fraction. In this manner, effective application and upgrading strategies could be individually designed for each fraction. [ABSTRACT FROM AUTHOR]