Adsorção de íons fosfato em óxido de nióbio hidratado
Autor(a) principal: | |
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Data de Publicação: | 2009 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Química Nova (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422009000500023 |
Resumo: | The adsorption kinetics of phosphate on Nb2O5.nH2O was investigated at initial phosphate concentrations 0.25, 0.50 and 1.00 mg.L-1. The kinetic process was described by a pseudo-second-order rate model very well. The adsorption thermodynamics was carried out at 298, 308, 318, 328 and 338 K. The positive values of both ΔH and ΔS suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. ΔG values obtained were negative indicating a spontaneous adsorption process. The Langmuir model described the data better than the Freundlich isotherm model. The effective desorption could be achieved using water at pH 12. |
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Adsorção de íons fosfato em óxido de nióbio hidratadoadsorption of phosphate ionskinetics modelsLangmuirThe adsorption kinetics of phosphate on Nb2O5.nH2O was investigated at initial phosphate concentrations 0.25, 0.50 and 1.00 mg.L-1. The kinetic process was described by a pseudo-second-order rate model very well. The adsorption thermodynamics was carried out at 298, 308, 318, 328 and 338 K. The positive values of both ΔH and ΔS suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. ΔG values obtained were negative indicating a spontaneous adsorption process. The Langmuir model described the data better than the Freundlich isotherm model. The effective desorption could be achieved using water at pH 12.Sociedade Brasileira de Química2009-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422009000500023Química Nova v.32 n.5 2009reponame:Química Nova (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0100-40422009000500023info:eu-repo/semantics/openAccessRodrigues,Liana AlvaresSilva,Maria Lúcia Caetano Pinto dapor2009-07-30T00:00:00Zoai:scielo:S0100-40422009000500023Revistahttps://www.scielo.br/j/qn/ONGhttps://old.scielo.br/oai/scielo-oai.phpquimicanova@sbq.org.br1678-70640100-4042opendoar:2009-07-30T00:00Química Nova (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
Adsorção de íons fosfato em óxido de nióbio hidratado |
title |
Adsorção de íons fosfato em óxido de nióbio hidratado |
spellingShingle |
Adsorção de íons fosfato em óxido de nióbio hidratado Rodrigues,Liana Alvares adsorption of phosphate ions kinetics models Langmuir |
title_short |
Adsorção de íons fosfato em óxido de nióbio hidratado |
title_full |
Adsorção de íons fosfato em óxido de nióbio hidratado |
title_fullStr |
Adsorção de íons fosfato em óxido de nióbio hidratado |
title_full_unstemmed |
Adsorção de íons fosfato em óxido de nióbio hidratado |
title_sort |
Adsorção de íons fosfato em óxido de nióbio hidratado |
author |
Rodrigues,Liana Alvares |
author_facet |
Rodrigues,Liana Alvares Silva,Maria Lúcia Caetano Pinto da |
author_role |
author |
author2 |
Silva,Maria Lúcia Caetano Pinto da |
author2_role |
author |
dc.contributor.author.fl_str_mv |
Rodrigues,Liana Alvares Silva,Maria Lúcia Caetano Pinto da |
dc.subject.por.fl_str_mv |
adsorption of phosphate ions kinetics models Langmuir |
topic |
adsorption of phosphate ions kinetics models Langmuir |
description |
The adsorption kinetics of phosphate on Nb2O5.nH2O was investigated at initial phosphate concentrations 0.25, 0.50 and 1.00 mg.L-1. The kinetic process was described by a pseudo-second-order rate model very well. The adsorption thermodynamics was carried out at 298, 308, 318, 328 and 338 K. The positive values of both ΔH and ΔS suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. ΔG values obtained were negative indicating a spontaneous adsorption process. The Langmuir model described the data better than the Freundlich isotherm model. The effective desorption could be achieved using water at pH 12. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009-01-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422009000500023 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422009000500023 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
10.1590/S0100-40422009000500023 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Química Nova v.32 n.5 2009 reponame:Química Nova (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Química Nova (Online) |
collection |
Química Nova (Online) |
repository.name.fl_str_mv |
Química Nova (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
quimicanova@sbq.org.br |
_version_ |
1750318109154082816 |