Rehydration of katoite as a layered double hydroxide: An in situ study
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.21809/rilemtechlett.2021.130 http://hdl.handle.net/11449/233112 |
Resumo: | Calcium aluminate layered double hydroxides (Ca-Al LDHs) constitute a considerable part of cementitious waste fines. Although cementitious waste fines have proven to be recyclable by thermal treatment at moderate temperatures (400–700 °C), understanding how each phase rehydrates and contributes to the binding properties of rehydrated cementitious materials is still necessary. In this study, the dehydration and rehydration of katoite are investigated through in situ techniques, and its applicability as an alternative binder or supplementary cementitious material (SCM) is discussed. The research employed X-ray diffraction, isothermal calorimetry, in situ wide-angle X-ray scattering (WAXS), and rotational/oscillatory rheometry. Katoite synthesized by a mechanochemical process (with contamination of calcite) was dehydrated at 400 °C, producing mainly mayenite. During rehydration, calorimetry presents high heat production in the first minutes. WAXS shows prompt recovery of katoite and increasing formation of monocarboaluminate (Ca-Al LDH) after 30 s of rehydration. The findings confirm the direct association between rapid heat release and phase reformation. Rehydrated pastes present a high yield stress and an increasing storage modulus, indicating rapid binding properties. The consolidation is also correlated with cumulative heat and monocarboaluminate formation. The results indicate the potential of calcined katoite (with presence of calcite) for use as rapid set alternative binder or SCM. |
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Rehydration of katoite as a layered double hydroxide: An in situ studyAlternative binderCalcium aluminatesKatoiteLayered double hydroxideRehydrationCalcium aluminate layered double hydroxides (Ca-Al LDHs) constitute a considerable part of cementitious waste fines. Although cementitious waste fines have proven to be recyclable by thermal treatment at moderate temperatures (400–700 °C), understanding how each phase rehydrates and contributes to the binding properties of rehydrated cementitious materials is still necessary. In this study, the dehydration and rehydration of katoite are investigated through in situ techniques, and its applicability as an alternative binder or supplementary cementitious material (SCM) is discussed. The research employed X-ray diffraction, isothermal calorimetry, in situ wide-angle X-ray scattering (WAXS), and rotational/oscillatory rheometry. Katoite synthesized by a mechanochemical process (with contamination of calcite) was dehydrated at 400 °C, producing mainly mayenite. During rehydration, calorimetry presents high heat production in the first minutes. WAXS shows prompt recovery of katoite and increasing formation of monocarboaluminate (Ca-Al LDH) after 30 s of rehydration. The findings confirm the direct association between rapid heat release and phase reformation. Rehydrated pastes present a high yield stress and an increasing storage modulus, indicating rapid binding properties. The consolidation is also correlated with cumulative heat and monocarboaluminate formation. The results indicate the potential of calcined katoite (with presence of calcite) for use as rapid set alternative binder or SCM.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Department of Construction Engineering Escola Politécnica University of São PauloInstitute of Chemistry São Paulo State UniversityDepartment of Metallurgical and Materials Engineering Escola Politécnica University of São PauloInstitute of Chemistry São Paulo State UniversityCNPq: 140054/2020-0FAPESP: 2014/50948-3FAPESP: 2019/27284-5CNPq: 305564/2018-8Universidade de São Paulo (USP)Universidade Estadual Paulista (UNESP)Pacheco, Antonia A. L.Nobre, Thiago R. S.Maciel, Marcel H.Santilli, Celso V. [UNESP]Coelho, Antonio C. VieiraAngulo, Sérgio C.2022-05-01T03:42:51Z2022-05-01T03:42:51Z2021-01-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article8-16http://dx.doi.org/10.21809/rilemtechlett.2021.130RILEM Technical Letters, v. 6, p. 8-16.2518-0231http://hdl.handle.net/11449/23311210.21809/rilemtechlett.2021.1302-s2.0-85103432571Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengRILEM Technical Lettersinfo:eu-repo/semantics/openAccess2022-05-01T03:42:51Zoai:repositorio.unesp.br:11449/233112Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462022-05-01T03:42:51Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Rehydration of katoite as a layered double hydroxide: An in situ study |
title |
Rehydration of katoite as a layered double hydroxide: An in situ study |
spellingShingle |
Rehydration of katoite as a layered double hydroxide: An in situ study Pacheco, Antonia A. L. Alternative binder Calcium aluminates Katoite Layered double hydroxide Rehydration |
title_short |
Rehydration of katoite as a layered double hydroxide: An in situ study |
title_full |
Rehydration of katoite as a layered double hydroxide: An in situ study |
title_fullStr |
Rehydration of katoite as a layered double hydroxide: An in situ study |
title_full_unstemmed |
Rehydration of katoite as a layered double hydroxide: An in situ study |
title_sort |
Rehydration of katoite as a layered double hydroxide: An in situ study |
author |
Pacheco, Antonia A. L. |
author_facet |
Pacheco, Antonia A. L. Nobre, Thiago R. S. Maciel, Marcel H. Santilli, Celso V. [UNESP] Coelho, Antonio C. Vieira Angulo, Sérgio C. |
author_role |
author |
author2 |
Nobre, Thiago R. S. Maciel, Marcel H. Santilli, Celso V. [UNESP] Coelho, Antonio C. Vieira Angulo, Sérgio C. |
author2_role |
author author author author author |
dc.contributor.none.fl_str_mv |
Universidade de São Paulo (USP) Universidade Estadual Paulista (UNESP) |
dc.contributor.author.fl_str_mv |
Pacheco, Antonia A. L. Nobre, Thiago R. S. Maciel, Marcel H. Santilli, Celso V. [UNESP] Coelho, Antonio C. Vieira Angulo, Sérgio C. |
dc.subject.por.fl_str_mv |
Alternative binder Calcium aluminates Katoite Layered double hydroxide Rehydration |
topic |
Alternative binder Calcium aluminates Katoite Layered double hydroxide Rehydration |
description |
Calcium aluminate layered double hydroxides (Ca-Al LDHs) constitute a considerable part of cementitious waste fines. Although cementitious waste fines have proven to be recyclable by thermal treatment at moderate temperatures (400–700 °C), understanding how each phase rehydrates and contributes to the binding properties of rehydrated cementitious materials is still necessary. In this study, the dehydration and rehydration of katoite are investigated through in situ techniques, and its applicability as an alternative binder or supplementary cementitious material (SCM) is discussed. The research employed X-ray diffraction, isothermal calorimetry, in situ wide-angle X-ray scattering (WAXS), and rotational/oscillatory rheometry. Katoite synthesized by a mechanochemical process (with contamination of calcite) was dehydrated at 400 °C, producing mainly mayenite. During rehydration, calorimetry presents high heat production in the first minutes. WAXS shows prompt recovery of katoite and increasing formation of monocarboaluminate (Ca-Al LDH) after 30 s of rehydration. The findings confirm the direct association between rapid heat release and phase reformation. Rehydrated pastes present a high yield stress and an increasing storage modulus, indicating rapid binding properties. The consolidation is also correlated with cumulative heat and monocarboaluminate formation. The results indicate the potential of calcined katoite (with presence of calcite) for use as rapid set alternative binder or SCM. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-01-01 2022-05-01T03:42:51Z 2022-05-01T03:42:51Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.21809/rilemtechlett.2021.130 RILEM Technical Letters, v. 6, p. 8-16. 2518-0231 http://hdl.handle.net/11449/233112 10.21809/rilemtechlett.2021.130 2-s2.0-85103432571 |
url |
http://dx.doi.org/10.21809/rilemtechlett.2021.130 http://hdl.handle.net/11449/233112 |
identifier_str_mv |
RILEM Technical Letters, v. 6, p. 8-16. 2518-0231 10.21809/rilemtechlett.2021.130 2-s2.0-85103432571 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
RILEM Technical Letters |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
8-16 |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
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1803649280607518720 |