Bartle, KD
1992
High-Resolution Chromatographic Characterization of Depolymerized Coals of Different Rank: Aliphatic and Aromatic Hydrocarbons
Carlson, R.E.; Critchfield, S.; Vorkink, W.P.; Dong, J.-Z.; Pugmire, R.J.; Bartle, K.D.; Lee, M.L.; Zhang, Y. and Shabtai, J.S.
Fuel, 71(1):1-29, 1992. Funded by US Department of Energy, Gas Research Institute and ACERC.
A selective, low temperature depolymerization procedure has been applied to four Argonne coals of different rank to produce products that are representative of the original coal macromolecular structure, and that are amenable to chromatographic analysis. The products of this depolymerization procedure retained most of the original aromatic and functional group structures of the original coals. A comparison of liquid C-13 NMR spectra of the products and solid-state C-13 NMR spectra of the original coals showed only minor changes in the aromaticities of two of the coals, and some loss of the carbonyl carbons in all of the coals.
Tetrahydrofuran pre-extracts of the four coals and their depolymerized products were separated into chemical classes by adsorption chromatography. Two of these fractions, which contained aliphatic hydrocarbons and polycyclic aromatic hydrocarbons were analyzed using gas chromatography/mass spectrometry. Structural identifications were based on a combination of chromatographic retention and mass spectral fragmentation data. For the lower rank coals, the compositions of the pre-extracts were quite different from the corresponding depolymerized products, and they contained an abundance of molecular biological markers. The compositions of the pre-extracts became more similar to the depolymerized products as rank increased.
1991
Structural Comparison of Low-Molecular-Weight Extractable Compounds in Different Rank Coals Using Capillary Column Gas Chromatography
Chang, H.-C.K.; Bartle, K.D.; Markides, K.E. and Lee, M.L.
Advances in Coal Spectroscopy, 141-164, (H.L.C. Meuzelaar, ed.), Plenum Publishing Corp., New York, 1991. Funded by Gas Research Institute and ACERC.
In this chapter, results from the analysis of the low-molecular-weight organic constituents in six vitrinite-rich coals of ranks ranging from lignite to low volatile bituminous are reported. Aliphatics, neutral aromatics, nitrogen-containing aromatics, and sulfur-containing aromatics were first isolated from the coal extracts using column absorption and complexation chromatography, and then they were resolved and identified using capillary column gas chromatography coupled with sulfur- and nitrogen-selective detectors, and mass spectrometry.
1990
High Resolution Chromatographic Characterization of Depolymerized Coals of Different Rank: Aliphatic and Aromatic Hydrocarbons
Carlson, R.E.; Critchfield, S.; Vorkink, W.P.; Dong, J.-Z.; Pugmire, R.J.; Bartle, K.D. and Lee, M.L.
Fuel, 1990 (In Press). Funded by US Department of Energy, Gas Research Institute and ACERC.
A selective, low temperature depolymerization procedure has been applied to four Argonne coals of different rank to produce products that are representative of the original coal macromolecular structure, and that are amenable to chromatographic analysis. The products of this depolymerization procedure retained most of the original aromatic and functional group structures of the original coals. A comparison of liquid C-13 NMR spectra of the products and solid-state C-13 NMR spectra of the original coals showed only minor changes in the aromaticities of two of the coals, and some loss of the carbonyl carbons in all of the coals.
Tetrahydrofuran pre-extracts of the four coals and their depolymerized products were separated into chemical classes by adsorption chromatography. Two of these fractions, which contained aliphatic hydrocarbons and polycyclic aromatic hydrocarbons were analyzed using gas chromatography/mass spectrometry. Structural identifications were based on a combination of chromatographic retention and mass spectral fragmentation data. For the lower rank coals, the compositions of the pre-extracts were quite different from the corresponding depolymerized products, and they contained an abundance of molecular biological markers. The compositions of the pre-extracts became more similar to the depolymerized products as rank increased.
1989
Multidimensional Open-Tubular Column Supercritical Fluid Chromatography Using a Flow-Switching Interface
Davies, I.L.; Xu, B.; Markides, K.E.; Bartle, K.D. and Lee, M.L.
J. Microcol. Sep., 2, 71, 1989. Funded by Gas Research Institute and the Utah Centers of Excellence.
A multidimensional system based on capillary supercritical fluid chromatography (SFC) was constructed that utilizes a simple flow-switching interface between two open-tubular 50-mm i.d. columns. A novel solvent-venting injection technique was incorporated in the system that enables single or multiple 0.5-mL volumes to be injected into an uncoated, yet deactivated, length of capillary precolumn without flooding of the analytical column. The effectiveness of multidimensional capillary SFC (SFC-SFC) for complex mixtures is demonstrated by the analysis of polycyclic aromatic hydrocarbons (PAH) in a coal tar extract, the trace determination of a methylcarbonate pesticide and its metabolites in a bird extract, and a group-type separation of hydrocarbons in a high-boiling petroleum distillate. These examples show for the first time that capillary SFC-SFC is a complementary alternative to other multidimensional chromatographic methods involving liquid or gaseous mobile phases.
1988
Identification and Comparison of Low-Molecular-Weight Neutral Constituents in Two Different Coal Extracts
Chang, H.-C.K.; Nishioka, M.; Bartle, K.D.; Wise, S.A.; Bayona, J.M.; Markides, K.E. and Lee, M.L.
Fuel, 67, 45-48, 1988. 4 pgs. Funded by Gas Research Institute.
Determination of the chemical structural features of coals is a continuing major goal of fuel science because of the vital energy source represented by this material. Coals are now perceived to be cross-linked macromolecular networks in which are trapped lower molecular weight materials either in sites readily accessible to solvent or in 'cages' analogous to clathrates. How representative this extractable material is of the multipolymeric macromolecular structure in which it is embedded in clearly open to question. However, the generally lower molecular weights of components in solvent extracts lead to much greater ease of analysis, and such extracts may provide insights into metamorphic changes undergone by the macromolecular structure during coal formation.
A two-step pyridine and then tetrahydrofuran solvent extraction procedure at room temperature under nitrogen gas flow was used to extract two different US coals, PSOC-592 (Illinois No. 5) and PSOC-521 (Rock Springs No. 7, Wyoming). Aliphatic and aromatic hydrocarbons were separated using neutral alumina column chromatography. The aromatics were then fractionated according to the number of aromatic carbons by high performance liquid chromatography. These neutral compounds were identified by gas chromatography (g.c.) and gas chromatography/mass spectrometry. n-Alkanes (C17-C31), pristane, phythane, hopanes (17aH, 21bH), and moretanes (17bH, 21aH) were found in aliphatic fractions of both coal extracts. Low-molecular-weight (2-4 rings) polycyclic aromatic hydrocarbons (PAH) were the major compounds in the aromatic fraction of the PSOC-592 coal extract. However, pentacyclic triterpenoid-like hydroaromatic hydrocarbons were the major components in the extract of the PSOC-521 coal. A number of new compounds were identified for the first time.
Bartle, KD
1992
High-Resolution Chromatographic Characterization of Depolymerized Coals of Different Rank: Aliphatic and Aromatic Hydrocarbons
Carlson, R.E.; Critchfield, S.; Vorkink, W.P.; Dong, J.-Z.; Pugmire, R.J.; Bartle, K.D.; Lee, M.L.; Zhang, Y. and Shabtai, J.S.
Fuel, 71(1):1-29, 1992. Funded by US Department of Energy, Gas Research Institute and ACERC.
A selective, low temperature depolymerization procedure has been applied to four Argonne coals of different rank to produce products that are representative of the original coal macromolecular structure, and that are amenable to chromatographic analysis. The products of this depolymerization procedure retained most of the original aromatic and functional group structures of the original coals. A comparison of liquid C-13 NMR spectra of the products and solid-state C-13 NMR spectra of the original coals showed only minor changes in the aromaticities of two of the coals, and some loss of the carbonyl carbons in all of the coals.
Tetrahydrofuran pre-extracts of the four coals and their depolymerized products were separated into chemical classes by adsorption chromatography. Two of these fractions, which contained aliphatic hydrocarbons and polycyclic aromatic hydrocarbons were analyzed using gas chromatography/mass spectrometry. Structural identifications were based on a combination of chromatographic retention and mass spectral fragmentation data. For the lower rank coals, the compositions of the pre-extracts were quite different from the corresponding depolymerized products, and they contained an abundance of molecular biological markers. The compositions of the pre-extracts became more similar to the depolymerized products as rank increased.
1991
Structural Comparison of Low-Molecular-Weight Extractable Compounds in Different Rank Coals Using Capillary Column Gas Chromatography
Chang, H.-C.K.; Bartle, K.D.; Markides, K.E. and Lee, M.L.
Advances in Coal Spectroscopy, 141-164, (H.L.C. Meuzelaar, ed.), Plenum Publishing Corp., New York, 1991. Funded by Gas Research Institute and ACERC.
In this chapter, results from the analysis of the low-molecular-weight organic constituents in six vitrinite-rich coals of ranks ranging from lignite to low volatile bituminous are reported. Aliphatics, neutral aromatics, nitrogen-containing aromatics, and sulfur-containing aromatics were first isolated from the coal extracts using column absorption and complexation chromatography, and then they were resolved and identified using capillary column gas chromatography coupled with sulfur- and nitrogen-selective detectors, and mass spectrometry.
1990
High Resolution Chromatographic Characterization of Depolymerized Coals of Different Rank: Aliphatic and Aromatic Hydrocarbons
Carlson, R.E.; Critchfield, S.; Vorkink, W.P.; Dong, J.-Z.; Pugmire, R.J.; Bartle, K.D. and Lee, M.L.
Fuel, 1990 (In Press). Funded by US Department of Energy, Gas Research Institute and ACERC.
A selective, low temperature depolymerization procedure has been applied to four Argonne coals of different rank to produce products that are representative of the original coal macromolecular structure, and that are amenable to chromatographic analysis. The products of this depolymerization procedure retained most of the original aromatic and functional group structures of the original coals. A comparison of liquid C-13 NMR spectra of the products and solid-state C-13 NMR spectra of the original coals showed only minor changes in the aromaticities of two of the coals, and some loss of the carbonyl carbons in all of the coals.
Tetrahydrofuran pre-extracts of the four coals and their depolymerized products were separated into chemical classes by adsorption chromatography. Two of these fractions, which contained aliphatic hydrocarbons and polycyclic aromatic hydrocarbons were analyzed using gas chromatography/mass spectrometry. Structural identifications were based on a combination of chromatographic retention and mass spectral fragmentation data. For the lower rank coals, the compositions of the pre-extracts were quite different from the corresponding depolymerized products, and they contained an abundance of molecular biological markers. The compositions of the pre-extracts became more similar to the depolymerized products as rank increased.
1989
Multidimensional Open-Tubular Column Supercritical Fluid Chromatography Using a Flow-Switching Interface
Davies, I.L.; Xu, B.; Markides, K.E.; Bartle, K.D. and Lee, M.L.
J. Microcol. Sep., 2, 71, 1989. Funded by Gas Research Institute and the Utah Centers of Excellence.
A multidimensional system based on capillary supercritical fluid chromatography (SFC) was constructed that utilizes a simple flow-switching interface between two open-tubular 50-mm i.d. columns. A novel solvent-venting injection technique was incorporated in the system that enables single or multiple 0.5-mL volumes to be injected into an uncoated, yet deactivated, length of capillary precolumn without flooding of the analytical column. The effectiveness of multidimensional capillary SFC (SFC-SFC) for complex mixtures is demonstrated by the analysis of polycyclic aromatic hydrocarbons (PAH) in a coal tar extract, the trace determination of a methylcarbonate pesticide and its metabolites in a bird extract, and a group-type separation of hydrocarbons in a high-boiling petroleum distillate. These examples show for the first time that capillary SFC-SFC is a complementary alternative to other multidimensional chromatographic methods involving liquid or gaseous mobile phases.
1988
Identification and Comparison of Low-Molecular-Weight Neutral Constituents in Two Different Coal Extracts
Chang, H.-C.K.; Nishioka, M.; Bartle, K.D.; Wise, S.A.; Bayona, J.M.; Markides, K.E. and Lee, M.L.
Fuel, 67, 45-48, 1988. 4 pgs. Funded by Gas Research Institute.
Determination of the chemical structural features of coals is a continuing major goal of fuel science because of the vital energy source represented by this material. Coals are now perceived to be cross-linked macromolecular networks in which are trapped lower molecular weight materials either in sites readily accessible to solvent or in 'cages' analogous to clathrates. How representative this extractable material is of the multipolymeric macromolecular structure in which it is embedded in clearly open to question. However, the generally lower molecular weights of components in solvent extracts lead to much greater ease of analysis, and such extracts may provide insights into metamorphic changes undergone by the macromolecular structure during coal formation.
A two-step pyridine and then tetrahydrofuran solvent extraction procedure at room temperature under nitrogen gas flow was used to extract two different US coals, PSOC-592 (Illinois No. 5) and PSOC-521 (Rock Springs No. 7, Wyoming). Aliphatic and aromatic hydrocarbons were separated using neutral alumina column chromatography. The aromatics were then fractionated according to the number of aromatic carbons by high performance liquid chromatography. These neutral compounds were identified by gas chromatography (g.c.) and gas chromatography/mass spectrometry. n-Alkanes (C17-C31), pristane, phythane, hopanes (17aH, 21bH), and moretanes (17bH, 21aH) were found in aliphatic fractions of both coal extracts. Low-molecular-weight (2-4 rings) polycyclic aromatic hydrocarbons (PAH) were the major compounds in the aromatic fraction of the PSOC-592 coal extract. However, pentacyclic triterpenoid-like hydroaromatic hydrocarbons were the major components in the extract of the PSOC-521 coal. A number of new compounds were identified for the first time.