Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite

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The effects on montmorillonite (Mt) and on sepiolite (Sep) of mechanical (60 and 180. s grinding time) and further thermal treatments (TT) at 500. °C during 24. h, for removing diuron from aqueous solutions were evaluated. The adsorbents and complexes formed were characterised. The specific surface...

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Autores principales: Maqueda, C., Dos Santos Afonso, M., Morillo, E., Torres Sánchez, R.M., Perez-Sayago, M., Undabeytia, T.
Formato: JOUR
Materias:
Adsorption
Diuron
Mechanical treatment
Montmorillonite
Sepiolite
Thermal treatment
Adsorption capacities
Hydrophobic surfaces
Mechanical treatments
Montmorillonites (Mt)
Negative surface charges
Specific surface area (SSA)
Clay minerals
Grinding (machining)
Heat treatment
Microporosity
Surface charge
Surface chemistry
Urea
Zeta potential
Herbicides
adsorption
aqueous solution
crystallinity
diuron
heating
montmorillonite
sepiolite
surface area
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_01691317_v72_n_p175_Maqueda
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
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spelling todo:paper_01691317_v72_n_p175_Maqueda2023-10-03T15:06:57Z Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite Maqueda, C. Dos Santos Afonso, M. Morillo, E. Torres Sánchez, R.M. Perez-Sayago, M. Undabeytia, T. Adsorption Diuron Mechanical treatment Montmorillonite Sepiolite Thermal treatment Adsorption capacities Diuron Hydrophobic surfaces Mechanical treatments Montmorillonites (Mt) Negative surface charges Sepiolite Specific surface area (SSA) Adsorption Clay minerals Grinding (machining) Heat treatment Microporosity Surface charge Surface chemistry Urea Zeta potential Herbicides adsorption aqueous solution crystallinity diuron heating montmorillonite sepiolite surface area The effects on montmorillonite (Mt) and on sepiolite (Sep) of mechanical (60 and 180. s grinding time) and further thermal treatments (TT) at 500. °C during 24. h, for removing diuron from aqueous solutions were evaluated. The adsorbents and complexes formed were characterised. The specific surface area (SSA), SEM, XRD and zeta potential of the clay mineral samples were determined. The SSA values showed an increase of 50% for ground Mt and a slight decrease for ground Sep. TT reduced SSA by 50% for the Sep samples, but similar values remained for the Mt samples. Both minerals showed a decrease in crystallinity with increasing grinding time and TT. The zeta potential showed an increased of the negative surface charge for the Mt ground samples, but no changes were noticed for the Sep ground samples. The Mt-TT samples showed a slight decrease whilst the Sep samples showed an increase of the negative surface charge in comparison to those without thermal treatment. The adsorption of diuron on Mt was lower than on Sep, and it decreased slightly after 60 and/or 180. s of grinding, despite the larger SSA values. This differences on the adsorption extent were probably due to the increased micropore surface. In contrast, thermal activation caused significantly increased adsorption, especially for the 180-s ground sample that was inversely correlated with the micropore surface, indicating that diuron was not adsorbed in micropores. Diuron adsorption on Sep was higher than on Mt due to its higher SSA. The adsorption capacity of Sep samples was increased by mechanical treatments (ground and sonicated). Moreover, thermal activation led to additional increases in adsorption probably due to changes in the Sep structure by the loss of OH structural groups leading to a more hydrophobic surface. Diuron adsorption on Mt-TT samples produced an increase in the negative surface charge compared to the original sample, whereas a decrease in the negative surface charge was observed for Sep. © 2012 Elsevier B.V. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_01691317_v72_n_p175_Maqueda
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Adsorption
Diuron
Mechanical treatment
Montmorillonite
Sepiolite
Thermal treatment
Adsorption capacities
Diuron
Hydrophobic surfaces
Mechanical treatments
Montmorillonites (Mt)
Negative surface charges
Sepiolite
Specific surface area (SSA)
Adsorption
Clay minerals
Grinding (machining)
Heat treatment
Microporosity
Surface charge
Surface chemistry
Urea
Zeta potential
Herbicides
adsorption
aqueous solution
crystallinity
diuron
heating
montmorillonite
sepiolite
surface area
spellingShingle Adsorption
Diuron
Mechanical treatment
Montmorillonite
Sepiolite
Thermal treatment
Adsorption capacities
Diuron
Hydrophobic surfaces
Mechanical treatments
Montmorillonites (Mt)
Negative surface charges
Sepiolite
Specific surface area (SSA)
Adsorption
Clay minerals
Grinding (machining)
Heat treatment
Microporosity
Surface charge
Surface chemistry
Urea
Zeta potential
Herbicides
adsorption
aqueous solution
crystallinity
diuron
heating
montmorillonite
sepiolite
surface area
Maqueda, C.
Dos Santos Afonso, M.
Morillo, E.
Torres Sánchez, R.M.
Perez-Sayago, M.
Undabeytia, T.
Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
topic_facet Adsorption
Diuron
Mechanical treatment
Montmorillonite
Sepiolite
Thermal treatment
Adsorption capacities
Diuron
Hydrophobic surfaces
Mechanical treatments
Montmorillonites (Mt)
Negative surface charges
Sepiolite
Specific surface area (SSA)
Adsorption
Clay minerals
Grinding (machining)
Heat treatment
Microporosity
Surface charge
Surface chemistry
Urea
Zeta potential
Herbicides
adsorption
aqueous solution
crystallinity
diuron
heating
montmorillonite
sepiolite
surface area
description The effects on montmorillonite (Mt) and on sepiolite (Sep) of mechanical (60 and 180. s grinding time) and further thermal treatments (TT) at 500. °C during 24. h, for removing diuron from aqueous solutions were evaluated. The adsorbents and complexes formed were characterised. The specific surface area (SSA), SEM, XRD and zeta potential of the clay mineral samples were determined. The SSA values showed an increase of 50% for ground Mt and a slight decrease for ground Sep. TT reduced SSA by 50% for the Sep samples, but similar values remained for the Mt samples. Both minerals showed a decrease in crystallinity with increasing grinding time and TT. The zeta potential showed an increased of the negative surface charge for the Mt ground samples, but no changes were noticed for the Sep ground samples. The Mt-TT samples showed a slight decrease whilst the Sep samples showed an increase of the negative surface charge in comparison to those without thermal treatment. The adsorption of diuron on Mt was lower than on Sep, and it decreased slightly after 60 and/or 180. s of grinding, despite the larger SSA values. This differences on the adsorption extent were probably due to the increased micropore surface. In contrast, thermal activation caused significantly increased adsorption, especially for the 180-s ground sample that was inversely correlated with the micropore surface, indicating that diuron was not adsorbed in micropores. Diuron adsorption on Sep was higher than on Mt due to its higher SSA. The adsorption capacity of Sep samples was increased by mechanical treatments (ground and sonicated). Moreover, thermal activation led to additional increases in adsorption probably due to changes in the Sep structure by the loss of OH structural groups leading to a more hydrophobic surface. Diuron adsorption on Mt-TT samples produced an increase in the negative surface charge compared to the original sample, whereas a decrease in the negative surface charge was observed for Sep. © 2012 Elsevier B.V.
format JOUR
author Maqueda, C.
Dos Santos Afonso, M.
Morillo, E.
Torres Sánchez, R.M.
Perez-Sayago, M.
Undabeytia, T.
author_facet Maqueda, C.
Dos Santos Afonso, M.
Morillo, E.
Torres Sánchez, R.M.
Perez-Sayago, M.
Undabeytia, T.
author_sort Maqueda, C.
title Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
title_short Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
title_full Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
title_fullStr Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
title_full_unstemmed Adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
title_sort adsorption of diuron on mechanically and thermally treated montmorillonite and sepiolite
url http://hdl.handle.net/20.500.12110/paper_01691317_v72_n_p175_Maqueda
work_keys_str_mv AT maquedac adsorptionofdiurononmechanicallyandthermallytreatedmontmorilloniteandsepiolite
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AT morilloe adsorptionofdiurononmechanicallyandthermallytreatedmontmorilloniteandsepiolite
AT torressanchezrm adsorptionofdiurononmechanicallyandthermallytreatedmontmorilloniteandsepiolite
AT perezsayagom adsorptionofdiurononmechanicallyandthermallytreatedmontmorilloniteandsepiolite
AT undabeytiat adsorptionofdiurononmechanicallyandthermallytreatedmontmorilloniteandsepiolite
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