Detailed Characterization of Petroleum Sulfonates by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Abstract

Petroleum sulfonates obtained from heavy vacuum gas oil (HVGO) were characterized by negative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry [(−) ESI FT-ICR MS] to better understand the chemical nature of their surface-active components. Electrospray ionization (ESI) analysis showed that sulfonates contain mainly O3S, O3S2, O4S, and NO3S classes, which means that the sulfonation reaction does not occur selectively for aromatic hydrocarbon (HC) class compounds because it also reacts with N, S, and O heteroatom classes. Because sulfonates were separated by solubility into lipophilic and hydrophilic categories, it was confirmed that the same classes compose hydrophilic and lipophilic sulfonates. Moreover, this procedure revealed that lipophilic sulfonate extracts contain organic acids (O2 class) that are related to the total acid number of the starting HVGO. However, selective isolation of the surface-active species using the “wet-silica” procedure allowed for detection that these compounds have a non-surface-active character because they do not interact with the water phase. The new structural information disclosed about petroleum sulfonates and their raw materials might encourage further studies on the rational design and synthesis of novel petroleum surfactants with the desired properties for industrial applications, such as chemical enhanced oil recovery (CEOR).

Characterization of Petroleum Compounds Adsorbed on Solids by Infrared Spectroscopy and Mass Spectrometry

“…For the synthetic solids (panels e and f of Figure ), the abundances of these functional groups were different, so that the band attributed to esters did not appear for SiO 2 and the band ascribed to highly conjugated carbonyls was more intense for Al 2 O 3 . This observation is consistent with the proven applicability of the methods used to extract interfacially active material (surfactants) from the crude oil using SiO 2 . , Figure S3 of the Supporting Information summarizes the areas calculated for the range of 1800–1500 cm –1 and includes hypothetical structures associated with each peak. Dotted circular lines indicate structural diversity around aromatic moieties.…”

“…This observation is consistent with the proven applicability of the methods used to extract interfacially active material (surfactants) from the crude oil using SiO 2 . 53,54 Figure S3 of the Supporting Information summarizes the areas calculated for the range of 1800−1500 cm −1 and includes hypothetical structures associated with each peak. Dotted circular lines indicate structural diversity around aromatic moieties.…”

Exploring Compositional Changes along In Situ Combustion and Their Implications on Emulsion Stabilization via Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS)

“…Interfacial material was isolated from samples following our previously reported protocols. , Approximately 100 mg of crude oil or emulsion was dissolved in 10 mL of toluene. For the separation procedure, 1.0 g of freshly prepared 40% SiO 2 –H 2 O was added to the previous mixture and transferred to a 60 cm × 8.0 mm glass column.…”

A systematic approach to measure the contents of mono- and di-sulfonates in petroleum sulfonates by the novel method of acid–base titration coupled with traditional two-phase titration

“…Thus, the amount of di-sulfonates can be calculated as 9.526 Â 10 À5 mol, and the contents of di-sulfonates as 1.559 Â 10 À3 mol g À1 . Given the average equivalent weight of di-sulfonates as 550 g mol À1 (M d ), 32,33 the titrimetric di-sulfonates mass was 5.2393 Â 10 À2 g. Therefore, the calculated contents of di-sulfonates in enriched di-sulfonates samples was 85.75%, which directly suggests that di-sulfonates have been effectively enriched. Fig.…”