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Flaviano Oliveira Silvério - One of the best experts on this subject based on the ideXlab platform.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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comparison between analytical pyrolysis and nitrobenzene oxidation for determination of syringyl guaiacyl ratio in eucalyptus spp lignin
Bioresources, 2008Co-Authors: Claudio F Lima, Flaviano Oliveira Silvério, Luiz C A Barbosa, Cristiana R. Marcelo, Jorge Luiz ColodetteAbstract:Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS) was applied to measure the lignin syringyl/guaiacyl (S/G) ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbohydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis were similar for all the species using the compounds Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol, vanillin, 4-ethylsyringol, 4vinylsyringol, homosyringaldehyde, acetosyringone, and syringylacetone, as lignin markers. The selected markers were efficient for the determination of S/G ratio in eucalyptus wood by Py-GC-MS. The Py-GC-MS technique produced results that are comparable to the nitrobenzene oxidation method, with the advantage of requiring small wood samples and a short analysis time.
Luiz C A Barbosa - One of the best experts on this subject based on the ideXlab platform.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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comparison between analytical pyrolysis and nitrobenzene oxidation for determination of syringyl guaiacyl ratio in eucalyptus spp lignin
Bioresources, 2008Co-Authors: Claudio F Lima, Flaviano Oliveira Silvério, Luiz C A Barbosa, Cristiana R. Marcelo, Jorge Luiz ColodetteAbstract:Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS) was applied to measure the lignin syringyl/guaiacyl (S/G) ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbohydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis were similar for all the species using the compounds Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol, vanillin, 4-ethylsyringol, 4vinylsyringol, homosyringaldehyde, acetosyringone, and syringylacetone, as lignin markers. The selected markers were efficient for the determination of S/G ratio in eucalyptus wood by Py-GC-MS. The Py-GC-MS technique produced results that are comparable to the nitrobenzene oxidation method, with the advantage of requiring small wood samples and a short analysis time.
Claudio F Lima - One of the best experts on this subject based on the ideXlab platform.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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comparison between analytical pyrolysis and nitrobenzene oxidation for determination of syringyl guaiacyl ratio in eucalyptus spp lignin
Bioresources, 2008Co-Authors: Claudio F Lima, Flaviano Oliveira Silvério, Luiz C A Barbosa, Cristiana R. Marcelo, Jorge Luiz ColodetteAbstract:Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS) was applied to measure the lignin syringyl/guaiacyl (S/G) ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbohydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis were similar for all the species using the compounds Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol, vanillin, 4-ethylsyringol, 4vinylsyringol, homosyringaldehyde, acetosyringone, and syringylacetone, as lignin markers. The selected markers were efficient for the determination of S/G ratio in eucalyptus wood by Py-GC-MS. The Py-GC-MS technique produced results that are comparable to the nitrobenzene oxidation method, with the advantage of requiring small wood samples and a short analysis time.
Jorge Luiz Colodette - One of the best experts on this subject based on the ideXlab platform.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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comparison between analytical pyrolysis and nitrobenzene oxidation for determination of syringyl guaiacyl ratio in eucalyptus spp lignin
Bioresources, 2008Co-Authors: Claudio F Lima, Flaviano Oliveira Silvério, Luiz C A Barbosa, Cristiana R. Marcelo, Jorge Luiz ColodetteAbstract:Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS) was applied to measure the lignin syringyl/guaiacyl (S/G) ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbohydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis were similar for all the species using the compounds Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol, vanillin, 4-ethylsyringol, 4vinylsyringol, homosyringaldehyde, acetosyringone, and syringylacetone, as lignin markers. The selected markers were efficient for the determination of S/G ratio in eucalyptus wood by Py-GC-MS. The Py-GC-MS technique produced results that are comparable to the nitrobenzene oxidation method, with the advantage of requiring small wood samples and a short analysis time.
Marcela N N Silva - One of the best experts on this subject based on the ideXlab platform.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
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in situ determination of the syringyl guaiacyl ratio of residual lignin in pre bleached eucalypt kraft pulps by analytical pyrolysis
Journal of Analytical and Applied Pyrolysis, 2015Co-Authors: Claudio F Lima, Marcela N N Silva, Luiz C A Barbosa, Jorge Luiz Colodette, Flaviano Oliveira SilvérioAbstract:Abstract Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis of residual lignins identified by mass spectrometry. A total of 18 compounds were identified, being nine derived from guaiacyl units and nine derived from syringyl lignin. The S/G ratios were calculated using the relative area of S-lignin (syringol, 4-methylsyringol, 4-vinylsyringol and trans -4-(prop-2-enyl) syringol) and G-lignin (Guaiacol, 4-methylGuaiacol, 4-vinylGuaiacol and trans -isoeugenol) as lignin markers. These studies showed that Py-GC/MS-SIM is an efficient tool to characterizing the chemical composition of residual lignin in oxygen pre-bleached Eucalyptus pulps.
