Hyphenation of supercritical fluid chromatography and two-dimensional gas chromatography–mass spectrometry for group type separations

Potgieter, H.; Westhuizen, Rina van der; Rohwer, Egmont Richard; Malan, D.

doi:10.1016/j.chroma.2013.04.020

Cited by 17 publications

(16 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another way of reducing the sample complexity prior to HT‐GC analysis is to apply a fractionation step prior to the analysis by GC . Solid‐phase extraction (SPE) is one of the most widely used methods for extraction, sample clean‐up, analyte concentration, and fractionation of organic compounds from a number of sample matrices .…”

Section: Introductionmentioning

confidence: 99%

“…Solid‐phase extraction (SPE) is one of the most widely used methods for extraction, sample clean‐up, analyte concentration, and fractionation of organic compounds from a number of sample matrices . HPLC fractionation has also been used extensively, and various methods utilising supercritical fluid chromatography (SFC) as an online fractionation step were published . Venter et al reported the group‐type analysis of oxygenated compounds with a silica gel porous layer open tubular (PLOT) column combined with comprehensive two‐dimensional SFC and GC (SFC × GC) as a means of oxygenate separation and identification.…”

Section: Introductionmentioning

confidence: 99%

“…6,7,[15][16][17][18][19][20][21] Another way of reducing the sample complexity prior to HT-GC analysis is to apply a fractionation step prior to the analysis by GC. [22][23][24][25][26] Solid-phase extraction (SPE) is one of the most widely used methods for extraction, sample clean-up, analyte concentration, and fractionation of organic compounds from a number of sample matrices. [27][28][29] HPLC fractionation has also been used extensively, 7,24,25 and various methods utilising supercritical fluid chromatography (SFC) as an online fractionation step were published.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The pre‐separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC‐MS with supersonic molecular beams.

et al. 2019

View full text Add to dashboard Cite

The heavy petroleum fractions produced during refining processes need to be upgraded to useable products to increase their value. Hydrogenated heavy paraffinic fractions can be oxidised to produce high value products that contain a variety of oxygenates. These heavy oxygenated paraffinic fractions need to be characterised to enable the control of oxidation processes and to understand product properties. The accurate identification of the oxygenates present in these fractions by electron ionisation (EI) mass spectrometry is challenging due to the complexity of these heavy fractions. Adding to this challenge is the limited applicability of EI mass spectral libraries due to the absence of molecular ions from the EI mass spectra of many oxygenates. The separation of oxygenates from the complex hydrocarbon matrix prior to high temperature GC‐MS (HT‐GC‐MS) analysis reduces the complexity of these fractions and assists in the accurate identification of these oxygenates. Solid phase extraction (SPE) and supercritical fluid chromatography (SFC) were employed as prefractionation techniques. GC‐MS with supersonic molecular beams (SMBs) (also named GC‐MS with cold‐EI) utilises a SMB interface with which EI is done with vibrationally cold sample compounds in a fly‐through ion source (cold‐EI) resulting in a substantial increase in the molecular ion signal intensity in the mass spectrum. This greatly enhances the accurate identification of the oxygenates in these fractions. This study investigated the ionisation behaviour of oxygenated compounds using cold‐EI. The prefractionation by SPE and SFC and the subsequent analysis with GC‐MS with cold‐EI were applied to an oxygenated heavy paraffinic fraction.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The pre‐separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC‐MS with supersonic molecular beams.

et al. 2019

View full text Add to dashboard Cite

show abstract

“…as an on-line pre-fractionation step were developed [16][17]. The hyphenation of SFC to GC×GC is less complicated and the removal of the supercritical CO 2 can be easily achieved without any loss of the volatile sample components or the introduction of coeluting solvents and their dilution effect.…”

Section: Introductionmentioning

confidence: 99%

“…The hyphenation of SFC to GC×GC is less complicated and the removal of the supercritical CO 2 can be easily achieved without any loss of the volatile sample components or the introduction of coeluting solvents and their dilution effect. The SFC method [17] separates the sample into four groups, namely (cyclic and non-cyclic) alkanes, (cyclic and non-cyclic) alkenes, aromatics and oxygenates. These groups were transferred separately to the GC×GC-TOF-MS in an on-line mode.…”

Section: Introductionmentioning

confidence: 99%

Two-dimensional gas chromatography-online hydrogenation for improved characterization of petrochemical samples

Potgieter

Bekker

Rohwer

2016

Journal of Chromatography A

Self Cite

View full text Add to dashboard Cite

The Fischer-Tropsch (FT) process produces a variety of hydrocarbons over a wide carbon number range and during subsequent product workup a large variety of synthetic fuels and chemicals are produced. The complexity of the product slate obtained from this process is well documented and the high temperature FT (HT-FT) process products are spread over gas, oil and water phases. The characterization of these phases is very challenging even when using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOF-MS). Despite the increase in separation power, peak coelution still occurs when samples containing isomeric compounds are analysed by comprehensive two dimensional GC. The separation of cyclic and double bond containing compounds and combinations thereof is especially difficult since these compounds elute in a similar position on the GC×GC chromatogram and have identical molecular masses and similar fragmentation patterns. Pre-separation of alkenes and alkanes with HPLC prior to the GC×GC-TOF-MS analysis was used to distinguish between the cyclic and non-cyclic isomers of both these compounds. Subsequently, a method utilizing supercritical fluid chromatography (SFC) as an on-line pre-fractionation step was also developed. These pre-fractionation methods cannot be used to distinguish between classes like dienes and cyclic olefins since both contain alkene double bonds that will form adducts with the silver ions in these methods. On-line hydrogenation after GC×GC separation is a possible way to distinguish between these compounds since the number of rings and alkene double bonds can be determined from the mass spectra of the compounds before and after hydrogenation. This paper describes development of a GC×GC method with post column hydrogenation for the determination of the backbone of cyclic/olefinic structures enabling 2 us to differentiate between classes like dienes and cyclic olefins in complex petrochemical streams.

show abstract

Supercritical Fluids in Chromatography

Thiébaut

Campbell

2020

Analytical Techniques in the Oil and Gas Industry for Environmental Monitoring

View full text Add to dashboard Cite

Hyphenation of supercritical fluid chromatography and two-dimensional gas chromatography–mass spectrometry for group type separations

Cited by 17 publications

References 31 publications

The pre‐separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC‐MS with supersonic molecular beams.

The pre‐separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC‐MS with supersonic molecular beams.

Two-dimensional gas chromatography-online hydrogenation for improved characterization of petrochemical samples

Supercritical Fluids in Chromatography

Contact Info

Product

Resources

About