Hervé Carrier

Direct multi-element analysis of crude oils and gas condensates by double-focusing sector field inductively coupled plasma mass spectrometry (ICP MS)

A double-focusing sector field ICP MS was optimized for the direct simultaneous determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sn, Ti, V in organic solutions. Polyatomic interferences originating from the carbon-rich matrix were completely eliminated at a resolution of 4000 allowing the detection limits at the low pg g−1 level to be obtained (typically one order of magnitude lower than using a quadrupole ICP MS). A method for the routine comprehensive trace element analysis of xylene solutions of oil samples using external calibration was developed. It was validated by the analysis of three certified reference materials and applied to the analysis of 2 gas condensate samples and 4 oil samples of different origins.

Multielement molecular size fractionation in crude oil and oil residue by size exclusion microchromatography with high resolution inductively coupled plasma mass spectrometric detection (HR ICP MS)

Microchromatography using permeation through gels with the increasing exclusion limit (5000, 400000 and 20000000 Da) was combined with high resolution (R = 4000) ICP MS to measure the distribution of Co, Cr, Fe, Ni, S, Si, V and Zn as a function of the molecular mass fraction of crude oil and oil vacuum distillation residue. The accuracy of the simultaneous multielement determination was verified by the µflow-injection-ICP MS analysis of certified reference materials (wear-metals in lubricating oils: SRM 1084a and SRM 1085b). The method allowed the acquisition of chromatograms with high sensitivity competitive existing methods, showing element- and sample origin-dependent morphology.

Petroleomics by Direct Analysis in Real Time-Mass Spectrometry

AbstractThe analysis of crude oil and its fractions by applying ambient ionization techniques remains underexplored in mass spectrometry (MS). Direct analysis in real time (DART) in the positive-ion mode was coupled to a linear quadrupole ion trap Orbitrap mass spectrometer (LTQ Orbitrap) to analyze crude oil, paraffin samples, and porphyrin standard compounds. The ionization parameters of DART-MS were optimized for crude oil analysis. DART-MS rendered the optimum conditions of the operation using paper as the substrate, T = 400°C, helium as the carrier gas, and a sample concentration ≥6 mg mL-1. In the crude oils analysis, the DART(+)-Orbitrap mass spectra detected the typical N, NO, and O-containing compounds. In the paraffin samples, oxidized hydrocarbon species (Ox classes, where x = 1–4) with double-bond equivalent of 1–4 were detected, and their structures and connectivity were confirmed by collision-induced dissociation (CID) experiments. DART(+)–MS has identified the porphyrin standard compounds as [M + H]+ ions of m/z 615.2502 and 680.1763, where M = C44H30N4 and C44H28N4OV, respectively, based on the formula assignment and by phenyl losses observed on CID experiments. Graphical Abstractᅟ

Compressibilities of liquid pentadecylcyclohexane and nonadecylcyclohexane from high pressure speed of sound and density measurements

The speed of sound in liquids pentadecylcyclohexane (C21H42) and nonadecylcyclohexane (C25H50) was measured by means of a pulse technique operating at 3 MHz. The measurements were carried out at pressures up to 150 MPa in the temperature range (303.15 to 383.15) K. Additional density measurements were performed up to p=60 MPa in the same range of temperature. From both measurements, the density was evaluated up to p=150 MPa and the isentropic compressibility was determined in the same pressure–temperature domain. The full density data were represented by a Tait-like equation in order to calculate the isothermal compressibility.