Comprehensive two-dimensional gas chromatography with time of flight mass spectrometry applied to analysis of Fischer-Tropsch synthesis products obtained with and without carbon dioxide addition to feed gas

Abstract

A cromatografia gasosa bidimensional abrangente acoplada à espectrometria de massas por tempo de vôo (CG×CG-EMTDV) foi aplicada para avaliar o efeito do CO 2 sobre a distribuição dos n-alcanos, alcanos ramificados, alquenos e compostos oxigenados em produtos da reação de Fischer-Tropsch. Coeluições de material não resolvido observadas em CG convencional foram resolvidas por CG×CG-EMTDV. Comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry (GC × GC-TOFMS) was applied to evaluate the CO 2 effect on distribution of n-alkanes, branched alkanes, alkenes and oxygen-containing compounds in Fischer-Tropsch products. GC × GC-TOFMS was able to resolve the unresolved compounds observed in conventional GC.

Evaluation of the composition of Carica papaya L. seed oil extracted with supercritical CO2

“…GC × GC can be coupled to several kinds of detectors [12] , but the most powerful combination is GC × GC coupled to time of flight mass spectrometry (GC × GC-TOFMS) because of its high acquisition rate (until 500 spectra s −1 ) [13] , [14] .…”

“…empty deactivated fused silica capillary, which was connected via SGE mini-unions and SiltiteTM 76 metal ferrules 0.1–0.25 mm i.d. (Ringwood, VIC, Australia) [14] .…”

Quantitative carbon distribution analysis of hydrocarbons, alcohols and carboxylic acids in a Fischer-Tropsch product from a Co/TiO2 catalyst during gas phase pilot plant operation

“…Additionally, aldehydes, ketones and ester can also be formed. There are numerous papers describing methods for analysis of the gas phase (Bertoncini et al 2009;Grobler et al 2009;Seomoon et al 2013;Pei et al 2015), aqueous phase (Anderson and White, 1994;Grobler et al 2009;Pei et al 2015;Ma et al 2019), liquid hydrocarbons and wax products (Bertoncini et al 2009;Grobler et al 2009;van der Westhuizen et al 2010;Silva et al 2011;Fernandes et al 2015;Pei et al 2015;Shafer et al 2019) but in general the quantitative distribution analysis of alcohols and carboxylic acids versus carbon chain length is difficult to achieve when these compounds are present at the low levels normally expected in a cobalt-catalysed FT product. This can be due to (i) the sensitivity of analytical methods at low oxygenate concentrations, (ii) the challenge of keeping high boiling point compounds in the vapour phase and then chromatographically separating a complex mixture of components when using on-line gas chromatography (GC) and (iii) the difficulty in obtaining an acceptable mass balance of all product phases when combining on-line and off-line analyses (Xiao et al 2017;Yang et al 2017).…”

“…Comprehensive two-dimensional chromatography (GCxGC) coupled with time-of-flight mass spectrometry has been used in many cases for the identification of trace components in FT products and sometimes quantification has also been given. Such examples show (i) the analysis of products from Co/Al 2 O 3 operated under slurry conditions demonstrating an Anderson-Schulz-Flory (ASF) plot of carbon distribution over the C 1 to C 20 range for paraffins, olefins and oxygenates (Bertoncini et al 2009); (ii) the quantification of 1-alcohols in liquid hydrocarbon from a Co/Al 2 O 3 catalyst (Silva et al 2011); (iii) the quantification of paraffins, olefins, aromatics and oxygenates in samples of oil made during high-temperature FT experiments (van der Westhuizen et al 2010); (iv) the quantification of paraffins, olefins, alcohols, aldehydes and carboxylic acids up to C 15 produced from a precipitated Fe catalyst in slurry operation (Grobler et al 2009); and (v) the simultaneous identification and quantification of alcohols and carboxylic acids, as their trimethylsilyl derivatives, in FT syn-crude and distilled products (Fernandes et al 2015). The use of supercritical fluid chromatography coupled with twodimensional gas chromatography-mass spectrometry for the separation and identification of saturated, unsaturated, aromatic and oxygenate species in hydrocarbon samples derived from a high-temperature FT reaction has also been demonstrated (Potgieter et al 2013), clearly indicating the diversity of class and number of organic compounds present in such products.…”