Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability

Detalhes bibliográficos
Autor(a) principal: Ascensão, G.
Data de Publicação: 2017
Outros Autores: Seabra, M. P., Aguiar, J. L. Barroso de, Labrincha, J. A.
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
Texto Completo: http://hdl.handle.net/1822/46665
Resumo: This study develop novel porous red mud (RM) based geopolymers and evaluates their potential to ensure prolonged pH control. Several properties of the novel geopolymers were examined including buffering ability, alkalis leaching behaviour, mineralogical composition, microstructure and physical properties. Two experimental plans were defined to evaluate the influence of porosity and RM content on those properties. The pH values of the eluted water and geopolymers OH ions leaching have been determined over time showing that total OH ions and the leaching rate can be tailored by controlling the geopolymers porous structure and the availability of free alkaline species. The lower pH gradient over 28th d (1.64 pH units) was achieved by combining a 0.025 wt% pore forming agent (aluminium powder) with 45 wt% MK replacement by red mud. A high and prolonged buffer capacity was accomplished, proving that red mud-based geopolymers have potential to be applied as pH buffering material.
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spelling Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering abilityAlkali leachingGeopolymerpH bufferingRed mudScience & TechnologyThis study develop novel porous red mud (RM) based geopolymers and evaluates their potential to ensure prolonged pH control. Several properties of the novel geopolymers were examined including buffering ability, alkalis leaching behaviour, mineralogical composition, microstructure and physical properties. Two experimental plans were defined to evaluate the influence of porosity and RM content on those properties. The pH values of the eluted water and geopolymers OH ions leaching have been determined over time showing that total OH ions and the leaching rate can be tailored by controlling the geopolymers porous structure and the availability of free alkaline species. The lower pH gradient over 28th d (1.64 pH units) was achieved by combining a 0.025 wt% pore forming agent (aluminium powder) with 45 wt% MK replacement by red mud. A high and prolonged buffer capacity was accomplished, proving that red mud-based geopolymers have potential to be applied as pH buffering material.This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersionElsevier ScienceUniversidade do MinhoAscensão, G.Seabra, M. P.Aguiar, J. L. Barroso deLabrincha, J. A.2017-032017-03-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/46665engAscensão G., Seabra M. P., Aguiar J. B., Labrincha J. A. Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability, Journal of Cleaner Production, Vol. 148, pp. 23-30, doi:10.1016/j.jclepro.2017.01.150, 20170959-652610.1016/j.jclepro.2017.01.150https://doi.org/10.1016/j.jclepro.2017.01.150info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T11:57:30Zoai:repositorium.sdum.uminho.pt:1822/46665Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T18:47:09.976482Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse
dc.title.none.fl_str_mv Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
title Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
spellingShingle Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
Ascensão, G.
Alkali leaching
Geopolymer
pH buffering
Red mud
Science & Technology
title_short Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
title_full Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
title_fullStr Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
title_full_unstemmed Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
title_sort Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability
author Ascensão, G.
author_facet Ascensão, G.
Seabra, M. P.
Aguiar, J. L. Barroso de
Labrincha, J. A.
author_role author
author2 Seabra, M. P.
Aguiar, J. L. Barroso de
Labrincha, J. A.
author2_role author
author
author
dc.contributor.none.fl_str_mv Universidade do Minho
dc.contributor.author.fl_str_mv Ascensão, G.
Seabra, M. P.
Aguiar, J. L. Barroso de
Labrincha, J. A.
dc.subject.por.fl_str_mv Alkali leaching
Geopolymer
pH buffering
Red mud
Science & Technology
topic Alkali leaching
Geopolymer
pH buffering
Red mud
Science & Technology
description This study develop novel porous red mud (RM) based geopolymers and evaluates their potential to ensure prolonged pH control. Several properties of the novel geopolymers were examined including buffering ability, alkalis leaching behaviour, mineralogical composition, microstructure and physical properties. Two experimental plans were defined to evaluate the influence of porosity and RM content on those properties. The pH values of the eluted water and geopolymers OH ions leaching have been determined over time showing that total OH ions and the leaching rate can be tailored by controlling the geopolymers porous structure and the availability of free alkaline species. The lower pH gradient over 28th d (1.64 pH units) was achieved by combining a 0.025 wt% pore forming agent (aluminium powder) with 45 wt% MK replacement by red mud. A high and prolonged buffer capacity was accomplished, proving that red mud-based geopolymers have potential to be applied as pH buffering material.
publishDate 2017
dc.date.none.fl_str_mv 2017-03
2017-03-01T00:00:00Z
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://hdl.handle.net/1822/46665
url http://hdl.handle.net/1822/46665
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Ascensão G., Seabra M. P., Aguiar J. B., Labrincha J. A. Red mud-based geopolymers with tailored alkali diffusion properties and pH buffering ability, Journal of Cleaner Production, Vol. 148, pp. 23-30, doi:10.1016/j.jclepro.2017.01.150, 2017
0959-6526
10.1016/j.jclepro.2017.01.150
https://doi.org/10.1016/j.jclepro.2017.01.150
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 Elsevier Science
publisher.none.fl_str_mv Elsevier Science
dc.source.none.fl_str_mv reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron:RCAAP
instname_str Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron_str RCAAP
institution RCAAP
reponame_str Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
collection Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
repository.name.fl_str_mv Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
repository.mail.fl_str_mv
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