Porosity of cellulose fibers chars activated by CO2

Detalhes bibliográficos
Autor(a) principal: Sousa, Jose Carlos
Data de Publicação: 2008
Outros Autores: Coutinho, Aparecido dos Reis, Barbieri, Fernando Cruz
Tipo de documento: Artigo
Idioma: por
Título da fonte: Acta scientiarum. Technology (Online)
Texto Completo: http://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/2781
Resumo: Porosity variation of activated carbons, prepared under different activation times and CO2 flows, is provided. Cellulose fibers of Eucalyptus saligna (Myrtaceae) wood were first pyrolysed in N2 with a heating rate of 5ºC min-1 , up to 800ºC. Samples were then activated at 850ºC, in CO2 flows of 15 to 120 mL min-1, during 1, 2 and 3 hours. Porosity of carbons was characterized by determining the burn-off grades of activated cellulose fibers, the specific surface areas SBET of the pores, the average radius of gyration of micropores Rg and the meso/macropores K/Q0 Porod relations. Concomitant increase of CO2 flow and activation time induced burn-off increase and micropores Rg reduction. However, improvement of SBET areas allows the authors to conclude that smaller size micropores were created in larger amounts. Under the same conditions, increases of K/Q0 indicated a sensitive creation of macropores and/or the mesopores coalescence
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spelling Porosity of cellulose fibers chars activated by CO2Estudo da porosidade de carvões de fibras de celulose ativados com CO2porosidadecarvões ativadosfibras de celulose1.05.00.00-6 FísicaPorosity variation of activated carbons, prepared under different activation times and CO2 flows, is provided. Cellulose fibers of Eucalyptus saligna (Myrtaceae) wood were first pyrolysed in N2 with a heating rate of 5ºC min-1 , up to 800ºC. Samples were then activated at 850ºC, in CO2 flows of 15 to 120 mL min-1, during 1, 2 and 3 hours. Porosity of carbons was characterized by determining the burn-off grades of activated cellulose fibers, the specific surface areas SBET of the pores, the average radius of gyration of micropores Rg and the meso/macropores K/Q0 Porod relations. Concomitant increase of CO2 flow and activation time induced burn-off increase and micropores Rg reduction. However, improvement of SBET areas allows the authors to conclude that smaller size micropores were created in larger amounts. Under the same conditions, increases of K/Q0 indicated a sensitive creation of macropores and/or the mesopores coalescenceO objetivo desse estudo foi caracterizar a variação da porosidade de carvões ativados, preparados sob diferentes tempos de ativação e fluxos de CO2. Fibras de celulose, provenientes da madeira de Eucalyptus saligna (Myrtaceae), foram inicialmente pirolisadas em atmosfera inerte de N2, sob taxa de aquecimento de 5ºC min-1, até 800ºC. As amostras carbonizadas foram ativadas a 850ºC, sob fluxos de 15 a 120 mL min-1 de CO2, por tempos de 1, 2 e 3 horas. A porosidade dos carvões foi caracterizada pela determinação dos graus de burn-off atingidos pelas fibras de celulose ativadas, das áreas superficiais especificas SBET dos seus poros, dos raios de giro médios Rg, dos seus microporos e das relações K/Q0 de Porod dos seus meso/macroporos. O aumento do tempo de ativação, concomitante com o aumento do fluxo de CO2, provocou o aumento do grau de burn-off e reduziu os Rg dos microporos. Entretanto, como foi observado um aumento das SBET, pode-se concluir que microporos de menores dimensões foram criados em quantidades maiores. Sob as mesmas condições, os aumentos das relações K/Q0 indicaram uma sensível criação de macroporos e/ou a coalescência de mesoporosUniversidade Estadual De Maringá2008-05-05info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttp://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/278110.4025/actascitechnol.v23i0.2781Acta Scientiarum. Technology; Vol 23 (2001); 1445-1448Acta Scientiarum. Technology; v. 23 (2001); 1445-14481806-25631807-8664reponame:Acta scientiarum. Technology (Online)instname:Universidade Estadual de Maringá (UEM)instacron:UEMporhttp://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/2781/1840Sousa, Jose CarlosCoutinho, Aparecido dos ReisBarbieri, Fernando Cruzinfo:eu-repo/semantics/openAccess2024-05-17T13:02:50Zoai:periodicos.uem.br/ojs:article/2781Revistahttps://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/indexPUBhttps://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/oai||actatech@uem.br1807-86641806-2563opendoar:2024-05-17T13:02:50Acta scientiarum. Technology (Online) - Universidade Estadual de Maringá (UEM)false
dc.title.none.fl_str_mv Porosity of cellulose fibers chars activated by CO2
Estudo da porosidade de carvões de fibras de celulose ativados com CO2
title Porosity of cellulose fibers chars activated by CO2
spellingShingle Porosity of cellulose fibers chars activated by CO2
Sousa, Jose Carlos
porosidade
carvões ativados
fibras de celulose
1.05.00.00-6 Física
title_short Porosity of cellulose fibers chars activated by CO2
title_full Porosity of cellulose fibers chars activated by CO2
title_fullStr Porosity of cellulose fibers chars activated by CO2
title_full_unstemmed Porosity of cellulose fibers chars activated by CO2
title_sort Porosity of cellulose fibers chars activated by CO2
author Sousa, Jose Carlos
author_facet Sousa, Jose Carlos
Coutinho, Aparecido dos Reis
Barbieri, Fernando Cruz
author_role author
author2 Coutinho, Aparecido dos Reis
Barbieri, Fernando Cruz
author2_role author
author
dc.contributor.author.fl_str_mv Sousa, Jose Carlos
Coutinho, Aparecido dos Reis
Barbieri, Fernando Cruz
dc.subject.por.fl_str_mv porosidade
carvões ativados
fibras de celulose
1.05.00.00-6 Física
topic porosidade
carvões ativados
fibras de celulose
1.05.00.00-6 Física
description Porosity variation of activated carbons, prepared under different activation times and CO2 flows, is provided. Cellulose fibers of Eucalyptus saligna (Myrtaceae) wood were first pyrolysed in N2 with a heating rate of 5ºC min-1 , up to 800ºC. Samples were then activated at 850ºC, in CO2 flows of 15 to 120 mL min-1, during 1, 2 and 3 hours. Porosity of carbons was characterized by determining the burn-off grades of activated cellulose fibers, the specific surface areas SBET of the pores, the average radius of gyration of micropores Rg and the meso/macropores K/Q0 Porod relations. Concomitant increase of CO2 flow and activation time induced burn-off increase and micropores Rg reduction. However, improvement of SBET areas allows the authors to conclude that smaller size micropores were created in larger amounts. Under the same conditions, increases of K/Q0 indicated a sensitive creation of macropores and/or the mesopores coalescence
publishDate 2008
dc.date.none.fl_str_mv 2008-05-05
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 http://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/2781
10.4025/actascitechnol.v23i0.2781
url http://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/2781
identifier_str_mv 10.4025/actascitechnol.v23i0.2781
dc.language.iso.fl_str_mv por
language por
dc.relation.none.fl_str_mv http://www.periodicos.uem.br/ojs/index.php/ActaSciTechnol/article/view/2781/1840
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Universidade Estadual De Maringá
publisher.none.fl_str_mv Universidade Estadual De Maringá
dc.source.none.fl_str_mv Acta Scientiarum. Technology; Vol 23 (2001); 1445-1448
Acta Scientiarum. Technology; v. 23 (2001); 1445-1448
1806-2563
1807-8664
reponame:Acta scientiarum. Technology (Online)
instname:Universidade Estadual de Maringá (UEM)
instacron:UEM
instname_str Universidade Estadual de Maringá (UEM)
instacron_str UEM
institution UEM
reponame_str Acta scientiarum. Technology (Online)
collection Acta scientiarum. Technology (Online)
repository.name.fl_str_mv Acta scientiarum. Technology (Online) - Universidade Estadual de Maringá (UEM)
repository.mail.fl_str_mv ||actatech@uem.br
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