| Title | Elemental and spectroscopic characterization of fractions of an acidic extract of oil sands process water |
| Author | Jones, D; Scarlett, A G; West, C E; Frank, R A; Gieleciak, R; Hager, D; Pureveen, J; Tegelaar, E; Rowland, S J |
| Source | Chemosphere vol. 93, issue 9, 2013 p. 1655-1664, https://doi.org/10.1016/j.chemosphere.2013.03.011 (Open Access) |
| Year | 2013 |
| Publisher | Elsevier BV |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | pdf |
| Subjects | oil sands; petroleum; spectroscopy; nitrogen; naphonic acids; oil sands process water; process water; spectroscopic; water; naphthenic; naphthenic acids; characterization; acidic; FTIR;
Multidimensional; solid phase extraction; phase; sulfur; extraction; chemosphere; GC-MS; aromatics |
| Illustrations | graphs; histograms |
| Released | 2013 07 12 |
| Abstract | 'Naphthenic acids' (NAs) in petroleum produced water and oil sands process water (OSPW), have been implicated in toxicological effects. However, many are not well characterized. A method for
fractionation of NAs of an OSPW was used herein and a multi-method characterization of the fractions conducted.
The unfractionated OSPW acidic extract was characterized by elemental analysis, electrospray ionization-Orbitrap-mass spectrometry
(ESI-MS), and an esterified extract by Fourier Transform infrared (FTIR) and ultraviolet–visible (UV) absorption spectroscopy and by comprehensive multidimensional gas chromatography–MS (GCxGC-MS). Methyl esters were fractionated by argentation solid
phase extraction (Ag+ SPE) and fractions eluting with: hexane; diethyl ether: hexane and diethyl ether, examined. Each was weighed, examined by elemental analysis, FTIR, UV, GC-MS and GCxGC-MS (both nominal and high resolution MS). The ether
fraction, containing sulfur, was also examined by GCxGC-sulfur chemiluminescence detection (GCxGC-SCD).
The major ions detected by ESI-MS in the OSPW extract were assigned to alicyclic and aromatic 'O2' acids; sulfur was also present. Components
recovered by Ag+ SPE were also methyl esters of alicyclic and aromatic acids; these contained little sulfur or nitrogen. FTIR spectra showed that hydroxy acids and sulfoxides were absent or minor. UV spectra, along with the C/H ratio, further
confirmed the aromaticity of the hexane:ether eluate.
The more minor ether eluate contained further aromatics and 1.5% sulfur. FTIR spectra indicated free carboxylic acids, in addition to esters. Four major sulfur compounds were detected by
GCxGC-SCD. GCxGC-high resolution MS indicated these were methyl esters of C18 S-containing, diaromatics with >=C3 carboxylic acid side chains. |
| Summary | (Plain Language Summary, not published)
'Naphthenic acids' (NAs) in petroleum produced water and oil sands process water (OSPW), have been implicated in toxicological effects. However, many are
not well characterized. A method for fractionation of NAs of an OSPW was used herein and a multi-method characterization of the fractions conducted. The unfractionated OSPW acidic extract was characterized by elemental analysis, electrospray
ionization-Orbitrap-mass spectrometry (ESI-MS), and an esterified extract by Fourier Transform infrared (FTIR) and ultraviolet-visible (UV) absorption spectroscopy and by comprehensive multidimensional gas chromatography-MS (GCxGC-MS). Methyl esters
were fractionated by argentation solid phase extraction (Ag+ SPE) and fractions eluting with: hexane; diethyl ether: hexane and diethyl ether, examined. Each was weighed, examined by elemental analysis, FTIR, UV, GC-MS and GCxGC-MS (both nominal and
high resolution MS). The ether fraction, containing sulfur, was also examined by GCxGC-sulfur chemiluminescence detection (GCxGC-SCD). The major ions detected by ESI-MS in the OSPW extract were assigned to alicyclic and aromatic 'O2' acids; sulfur
was also present. Components recovered by Ag+ SPE were also methyl esters of alicyclic and aromatic acids; these contained little sulfur or nitrogen. FTIR spectra showed that hydroxy acids and sulfoxides were absent or minor. UV spectra, along with
the C/H ratio, further confirmed the aromaticity of the hexane:ether eluate. The more minor ether eluate contained further aromatics and 1.5% sulfur. FTIR spectra indicated free carboxylic acids, in addition to esters. Four major sulfur compounds
were detected by GCxGC-SCD. GCxGC high resolution MS indicated these were methyl esters of C18 S-containing, diaromatics with C3 carboxylic acid side chains. |
| GEOSCAN ID | 298925 |
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