Modelling soil surface charge density using mineral composition

The proposed mathematical model consists of a first approach to estimate the soil composition from an experimental titration curve and the quantitative analysis of the soil mineral constituents. Mineral mixtures made using different percentages of kaolinite, illite and quartz were used to simulate a...

Descripción completa

Guardado en:
Detalles Bibliográficos
Publicado: 2004
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00167061_v121_n1-2_p123_Taubaso
http://hdl.handle.net/20.500.12110/paper_00167061_v121_n1-2_p123_Taubaso
Aporte de:
id paper:paper_00167061_v121_n1-2_p123_Taubaso
record_format dspace
spelling paper:paper_00167061_v121_n1-2_p123_Taubaso2023-06-08T14:38:46Z Modelling soil surface charge density using mineral composition Charge density Mathematical model Mineral mixtures Soils Composition Hydrochloric acid Ionic strength Kaolin Mixtures Quartz Silica Surface chemistry Illite Surface charges Soils clay mineral illite kaolinite numerical model quartz soil chemistry Argentina South America Argentina (fish) The proposed mathematical model consists of a first approach to estimate the soil composition from an experimental titration curve and the quantitative analysis of the soil mineral constituents. Mineral mixtures made using different percentages of kaolinite, illite and quartz were used to simulate a natural porous media and evaluate the proposed mathematical model assuming no interaction among the solid components of mixtures. Three soil samples from Argentine provinces collected from surface horizons (0-15 cm depth, horizon A1) and typified as Typic Haplocryoll, Rhodudult and Typic Hapludoll were titrated by successive additions of small volumes of 0.1 M HCl and/or KOH at ionic strength of 10-3, 10-2 and 10-1 M of KCl. Soils are strongly reflective of the individual point of zero charge (PZC) of the soil components. Iron oxides have high PZC values while silica, clays and soil organic matter have low PZC. In these soils, the difference between isoelectric point (IEP) and PZC was used to evaluate the existence of specific adsorption and the soils charge behaviour was fitted using the developed mathematical model. A theoretical titration curve was calculated using the charge density and area fraction of each soil or mineral mixtures components. The experimental and theoretical titration curves present a regression coefficient, R2, higher than 0.95 and a significant p-level p=0.00 for both, soils and mineral mixtures. This model could also be used to interpret the contaminants mobilization in the natural environments, which is dependent of the surface charges and on the mineralogical components of the soils as well as of the chemical interactions among contaminants and soil constituents. © 2003 Elsevier B.V. All rights reserved. 2004 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00167061_v121_n1-2_p123_Taubaso http://hdl.handle.net/20.500.12110/paper_00167061_v121_n1-2_p123_Taubaso
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Charge density
Mathematical model
Mineral mixtures
Soils
Composition
Hydrochloric acid
Ionic strength
Kaolin
Mixtures
Quartz
Silica
Surface chemistry
Illite
Surface charges
Soils
clay mineral
illite
kaolinite
numerical model
quartz
soil chemistry
Argentina
South America
Argentina (fish)
spellingShingle Charge density
Mathematical model
Mineral mixtures
Soils
Composition
Hydrochloric acid
Ionic strength
Kaolin
Mixtures
Quartz
Silica
Surface chemistry
Illite
Surface charges
Soils
clay mineral
illite
kaolinite
numerical model
quartz
soil chemistry
Argentina
South America
Argentina (fish)
Modelling soil surface charge density using mineral composition
topic_facet Charge density
Mathematical model
Mineral mixtures
Soils
Composition
Hydrochloric acid
Ionic strength
Kaolin
Mixtures
Quartz
Silica
Surface chemistry
Illite
Surface charges
Soils
clay mineral
illite
kaolinite
numerical model
quartz
soil chemistry
Argentina
South America
Argentina (fish)
description The proposed mathematical model consists of a first approach to estimate the soil composition from an experimental titration curve and the quantitative analysis of the soil mineral constituents. Mineral mixtures made using different percentages of kaolinite, illite and quartz were used to simulate a natural porous media and evaluate the proposed mathematical model assuming no interaction among the solid components of mixtures. Three soil samples from Argentine provinces collected from surface horizons (0-15 cm depth, horizon A1) and typified as Typic Haplocryoll, Rhodudult and Typic Hapludoll were titrated by successive additions of small volumes of 0.1 M HCl and/or KOH at ionic strength of 10-3, 10-2 and 10-1 M of KCl. Soils are strongly reflective of the individual point of zero charge (PZC) of the soil components. Iron oxides have high PZC values while silica, clays and soil organic matter have low PZC. In these soils, the difference between isoelectric point (IEP) and PZC was used to evaluate the existence of specific adsorption and the soils charge behaviour was fitted using the developed mathematical model. A theoretical titration curve was calculated using the charge density and area fraction of each soil or mineral mixtures components. The experimental and theoretical titration curves present a regression coefficient, R2, higher than 0.95 and a significant p-level p=0.00 for both, soils and mineral mixtures. This model could also be used to interpret the contaminants mobilization in the natural environments, which is dependent of the surface charges and on the mineralogical components of the soils as well as of the chemical interactions among contaminants and soil constituents. © 2003 Elsevier B.V. All rights reserved.
title Modelling soil surface charge density using mineral composition
title_short Modelling soil surface charge density using mineral composition
title_full Modelling soil surface charge density using mineral composition
title_fullStr Modelling soil surface charge density using mineral composition
title_full_unstemmed Modelling soil surface charge density using mineral composition
title_sort modelling soil surface charge density using mineral composition
publishDate 2004
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00167061_v121_n1-2_p123_Taubaso
http://hdl.handle.net/20.500.12110/paper_00167061_v121_n1-2_p123_Taubaso
_version_ 1768541687876943872