Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides

Layered double hydroxides (LDHs) present multiple applications due to their versatility and reactivity. Thus, Ca–Al LDHs with Friedel’s salt structure (HC) have been proposed as heavy metal scavengers due to their buffering capacity at basic pHs. Nevertheless, the control of the reactivity of LDHs s...

Descripción completa

Detalles Bibliográficos
Autores: Borgiallo, Andres, Rojas Delgado, Ricardo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/125635
Acceso en línea:http://hdl.handle.net/11336/125635
Access Level:acceso abierto
Palabra clave:CHELATION
HYDROCALUMITE
IONIC GELATION
PH BUFFERING
PRECIPITATION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
id AR_c1d94a54bedc1efa4e524ba3fbefef2b
oai_identifier_str oai:ri.conicet.gov.ar:11336/125635
network_acronym_str AR
network_name_str Argentina
spelling Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides Borgiallo, Andres Rojas Delgado, Ricardo CHELATION HYDROCALUMITE IONIC GELATION PH BUFFERING PRECIPITATION https://purl.org/becyt/ford/1.4 https://purl.org/becyt/ford/1 Layered double hydroxides (LDHs) present multiple applications due to their versatility and reactivity. Thus, Ca–Al LDHs with Friedel’s salt structure (HC) have been proposed as heavy metal scavengers due to their buffering capacity at basic pHs. Nevertheless, the control of the reactivity of LDHs such as HC is necessary to optimize their applications. Here, the reactivity of an HC prepared by a coprecipitation method was modified by its inclusion in calcium alginate (CaAlg) beads prepared by ionic gelation. The obtained beads (CaAlg/HC) showed good dispersion of the HC particles in the alginate matrix and were used to test the acid base reactivity and heavy metal uptake capacity compared with pure CaAlg beads and HC powder separately. The pH buffering capacity of CaAlg beads was enriched by the inclusion of HC that, in turn, was modulated in its reactivity. Thus, the HC dissolution times changed from mere seconds for the powder to tens of minutes when enclosed in the beads in a kinetic profile determined by the diffusive step. On the other hand, Cu2+ uptake capacity of CaAlg/HC beads combined the Cu(OH)2 precipitation capacity of HC with the complexation capacity of alginate, reaching good affinity and capacity for the obtained beads. Nevertheless, the precipitation of the hydroxide was produced outside the bead, which would induce the addition of an additional separation step to produce an acceptable Cu2+ elimination. Fil: Borgiallo, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Rojas Delgado, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina MDPI AG http://hdl.handle.net/11336/125635 Borgiallo, Andres; Rojas Delgado, Ricardo; Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides; MDPI AG; ChemEngineering; 3; 1; 3-2019; 1-13 2305-7084 CONICET Digital CONICET
title Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
spellingShingle Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
Borgiallo, Andres
CHELATION
HYDROCALUMITE
IONIC GELATION
PH BUFFERING
PRECIPITATION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
title_short Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
title_full Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
title_fullStr Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
title_full_unstemmed Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
title_sort Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides
author Borgiallo, Andres
author_facet Borgiallo, Andres
Rojas Delgado, Ricardo
author_role author
author2 Rojas Delgado, Ricardo
author2_role author
topic CHELATION
HYDROCALUMITE
IONIC GELATION
PH BUFFERING
PRECIPITATION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
topic_facet CHELATION
HYDROCALUMITE
IONIC GELATION
PH BUFFERING
PRECIPITATION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
description Layered double hydroxides (LDHs) present multiple applications due to their versatility and reactivity. Thus, Ca–Al LDHs with Friedel’s salt structure (HC) have been proposed as heavy metal scavengers due to their buffering capacity at basic pHs. Nevertheless, the control of the reactivity of LDHs such as HC is necessary to optimize their applications. Here, the reactivity of an HC prepared by a coprecipitation method was modified by its inclusion in calcium alginate (CaAlg) beads prepared by ionic gelation. The obtained beads (CaAlg/HC) showed good dispersion of the HC particles in the alginate matrix and were used to test the acid base reactivity and heavy metal uptake capacity compared with pure CaAlg beads and HC powder separately. The pH buffering capacity of CaAlg beads was enriched by the inclusion of HC that, in turn, was modulated in its reactivity. Thus, the HC dissolution times changed from mere seconds for the powder to tens of minutes when enclosed in the beads in a kinetic profile determined by the diffusive step. On the other hand, Cu2+ uptake capacity of CaAlg/HC beads combined the Cu(OH)2 precipitation capacity of HC with the complexation capacity of alginate, reaching good affinity and capacity for the obtained beads. Nevertheless, the precipitation of the hydroxide was produced outside the bead, which would induce the addition of an additional separation step to produce an acceptable Cu2+ elimination.
publishDate 2019
format article
status_str publishedVersion
url http://hdl.handle.net/11336/125635
identifier_str_mv Borgiallo, Andres; Rojas Delgado, Ricardo; Reactivity and heavy metal removal capacity of calcium alginate beads loaded with Ca–Al layered double hydroxides; MDPI AG; ChemEngineering; 3; 1; 3-2019; 1-13
2305-7084
CONICET Digital
CONICET
language eng
eu_rights_str_mv openAccess
publisher MDPI AG
institution Consejo Nacional de Investigaciones Científicas y Técnicas
collection CONICET Digital (CONICET)
reponame_str CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
_version_ 1878403794690113536
publishDateSort 2019
author_browse Borgiallo, Andres
Rojas Delgado, Ricardo
publisherStr MDPI AG
score 6,924472

Similares en LA Referencia