Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions
Autor(a) principal: | |
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Data de Publicação: | 2016 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFLA |
Texto Completo: | http://repositorio.ufla.br/jspui/handle/1/14809 |
Resumo: | Thermal treatment (thermal rectification) is a process in which technological properties of wood are modified using thermal energy, the result of which is often value-added wood. Thermally treated wood takes on similar color shades to tropical woods and offers considerable resistance to destructive microorganisms and climate action, in addition to having high dimensional stability and low hygroscopicity. Wood samples of Eucalyptus grandis were subjected to various thermal treatments, as performed in presence (140ºC; 160ºC; 180ºC) or in absence of oxygen (160ºC; 180ºC; 200ºC) inside a thermal treatment chamber, and then studied as to their chemical characteristics. Increasing the maximum treatment temperatures led to a reduction in the holocellulose content of samples as a result of the degradation and volatilization of hemicelluloses, also leading to an increase in the relative lignin content. Except for glucose, all monosaccharide levels were found to decrease in samples after the thermal treatment at a maximum temperature of 200ºC. The thermal treatment above 160ºC led to increased levels of total extractives in the wood samples, probably ascribed to the emergence of low molecular weight substances as a result of thermal degradation. Overall, it was not possible to clearly determine the effect of presence or absence of oxygen in the air during thermal treatment on the chemical characteristics of the relevant wood samples. |
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Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditionsEfeito da termorretificação nas características químicas da madeira de Eucalyptus grandis W. Hill ex Maiden tratada sob diferentes condições de atmosferaHeat treatmentWood chemistryEucalyptusTratamento térmicoQuímica da madeiraEucaliptoThermal treatment (thermal rectification) is a process in which technological properties of wood are modified using thermal energy, the result of which is often value-added wood. Thermally treated wood takes on similar color shades to tropical woods and offers considerable resistance to destructive microorganisms and climate action, in addition to having high dimensional stability and low hygroscopicity. Wood samples of Eucalyptus grandis were subjected to various thermal treatments, as performed in presence (140ºC; 160ºC; 180ºC) or in absence of oxygen (160ºC; 180ºC; 200ºC) inside a thermal treatment chamber, and then studied as to their chemical characteristics. Increasing the maximum treatment temperatures led to a reduction in the holocellulose content of samples as a result of the degradation and volatilization of hemicelluloses, also leading to an increase in the relative lignin content. Except for glucose, all monosaccharide levels were found to decrease in samples after the thermal treatment at a maximum temperature of 200ºC. The thermal treatment above 160ºC led to increased levels of total extractives in the wood samples, probably ascribed to the emergence of low molecular weight substances as a result of thermal degradation. Overall, it was not possible to clearly determine the effect of presence or absence of oxygen in the air during thermal treatment on the chemical characteristics of the relevant wood samples.A termorretificação (ou retificação térmica) é um processo de alteração das propriedades tecnológicas da madeira, utilizando-se energia térmica, cujos resultados obtidos, normalmente, resultam na agregação de valor à madeira. A madeira termorretificada adquire colorações semelhantes àquelas de madeiras tropicais, considerável resistência aos microorganismos xilófagos e à ação climática, alta estabilidade dimensional e baixa higroscopicidade. Amostras de Eucalyptus grandis foram submetidas a diversos tratamentos de termorretificação, executados em presença (140ºC; 160ºC; 180ºC) ou escassez de oxigênio (160ºC; 180ºC; 200ºC) na atmosfera do interior da câmara de tratamento térmico, e estudadas quanto às suas características químicas. O aumento das temperaturas máximas de tratamento causou redução no teor de holocelulose das amostras, em razão da degradação e volatilização de hemiceluloses, além de proporcionar um incremento no teor relativo de lignina. Todos os monossacarídeos, com exceção da glicose, tiveram sua proporção reduzida na madeira após o tratamento térmico à temperatura máxima de 200ºC. A termorretificação acima de 160ºC levou a um incremento no teor de extrativos totais da madeira, provavelmente atribuído ao surgimento de substâncias de peso molecular reduzido, em razão da degradação térmica. De maneira geral, não foi possível determinar com clareza o efeito das condições de presença ou escassez de oxigênio do ar durante a termorretificação sobre as características químicas da madeira tratada.Universidade Federal de Lavras (UFLA)2016-04-052017-08-01T20:17:04Z2017-08-01T20:17:04Z2017-08-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfMOURA, L. F. de; BRITO, J. O.; SILVA JÚNIOR, F. G. da. Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions. CERNE, Lavras, v. 18, n. 3, p. 449-455, jul./set. 2012.http://repositorio.ufla.br/jspui/handle/1/148092317-63420104-7760reponame:Repositório Institucional da UFLAinstname:Universidade Federal de Lavras (UFLA)instacron:UFLAengCopyright (c) 2016 CERNEAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/info:eu-repo/semantics/openAccessMoura, Luiz Fernando deBrito, José OtávioSilva Júnior, Francides Gomes da2021-02-27T20:04:32Zoai:localhost:1/14809Repositório InstitucionalPUBhttp://repositorio.ufla.br/oai/requestnivaldo@ufla.br || repositorio.biblioteca@ufla.bropendoar:2021-02-27T20:04:32Repositório Institucional da UFLA - Universidade Federal de Lavras (UFLA)false |
dc.title.none.fl_str_mv |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions Efeito da termorretificação nas características químicas da madeira de Eucalyptus grandis W. Hill ex Maiden tratada sob diferentes condições de atmosfera |
title |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
spellingShingle |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions Moura, Luiz Fernando de Heat treatment Wood chemistry Eucalyptus Tratamento térmico Química da madeira Eucalipto |
title_short |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
title_full |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
title_fullStr |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
title_full_unstemmed |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
title_sort |
Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions |
author |
Moura, Luiz Fernando de |
author_facet |
Moura, Luiz Fernando de Brito, José Otávio Silva Júnior, Francides Gomes da |
author_role |
author |
author2 |
Brito, José Otávio Silva Júnior, Francides Gomes da |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Moura, Luiz Fernando de Brito, José Otávio Silva Júnior, Francides Gomes da |
dc.subject.por.fl_str_mv |
Heat treatment Wood chemistry Eucalyptus Tratamento térmico Química da madeira Eucalipto |
topic |
Heat treatment Wood chemistry Eucalyptus Tratamento térmico Química da madeira Eucalipto |
description |
Thermal treatment (thermal rectification) is a process in which technological properties of wood are modified using thermal energy, the result of which is often value-added wood. Thermally treated wood takes on similar color shades to tropical woods and offers considerable resistance to destructive microorganisms and climate action, in addition to having high dimensional stability and low hygroscopicity. Wood samples of Eucalyptus grandis were subjected to various thermal treatments, as performed in presence (140ºC; 160ºC; 180ºC) or in absence of oxygen (160ºC; 180ºC; 200ºC) inside a thermal treatment chamber, and then studied as to their chemical characteristics. Increasing the maximum treatment temperatures led to a reduction in the holocellulose content of samples as a result of the degradation and volatilization of hemicelluloses, also leading to an increase in the relative lignin content. Except for glucose, all monosaccharide levels were found to decrease in samples after the thermal treatment at a maximum temperature of 200ºC. The thermal treatment above 160ºC led to increased levels of total extractives in the wood samples, probably ascribed to the emergence of low molecular weight substances as a result of thermal degradation. Overall, it was not possible to clearly determine the effect of presence or absence of oxygen in the air during thermal treatment on the chemical characteristics of the relevant wood samples. |
publishDate |
2016 |
dc.date.none.fl_str_mv |
2016-04-05 2017-08-01T20:17:04Z 2017-08-01T20:17:04Z 2017-08-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
MOURA, L. F. de; BRITO, J. O.; SILVA JÚNIOR, F. G. da. Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions. CERNE, Lavras, v. 18, n. 3, p. 449-455, jul./set. 2012. http://repositorio.ufla.br/jspui/handle/1/14809 |
identifier_str_mv |
MOURA, L. F. de; BRITO, J. O.; SILVA JÚNIOR, F. G. da. Effect of the thermal treatment on the chemical characteristics of wood from Eucalyptus grandis W. Hill ex Maiden under different atmospheric conditions. CERNE, Lavras, v. 18, n. 3, p. 449-455, jul./set. 2012. |
url |
http://repositorio.ufla.br/jspui/handle/1/14809 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
Copyright (c) 2016 CERNE Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Copyright (c) 2016 CERNE Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Lavras (UFLA) |
publisher.none.fl_str_mv |
Universidade Federal de Lavras (UFLA) |
dc.source.none.fl_str_mv |
2317-6342 0104-7760 reponame:Repositório Institucional da UFLA instname:Universidade Federal de Lavras (UFLA) instacron:UFLA |
instname_str |
Universidade Federal de Lavras (UFLA) |
instacron_str |
UFLA |
institution |
UFLA |
reponame_str |
Repositório Institucional da UFLA |
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Repositório Institucional da UFLA |
repository.name.fl_str_mv |
Repositório Institucional da UFLA - Universidade Federal de Lavras (UFLA) |
repository.mail.fl_str_mv |
nivaldo@ufla.br || repositorio.biblioteca@ufla.br |
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1815439364913627136 |