Details
| Original language | English |
|---|---|
| Pages (from-to) | 8-14 |
| Number of pages | 7 |
| Journal | Geoderma |
| Volume | 286 |
| Early online date | 28 Oct 2016 |
| Publication status | Published - 15 Jan 2017 |
Abstract
In soils, dispersion is a crucial step preceding the loss of clay-sized particles by surface run-off and leaching, which in turn results in soil degradation. Despite the fact that silicic acid is common in soil solutions, its effect on aggregation stability of fine sized particles in soils has not been detailed. Here we examined the effect of silicic acid on dispersion of a kaolinitic soil clay fraction rich in Fe-oxides (8.5%) at different pH values by combining dynamic light scattering for particle sizing and test tube experiments for examination of particles in suspension. Adsorption of silicic acid on the clay fraction was characterized by batch adsorption experiments and effects on surface charge by zeta potential (ζ) measurements over a pH range from 2 to 11. We found that silicic acid adsorbed onto clay and co-existing Fe oxides, made ζ more negative, and thereby counteracted aggregation of the clay fraction. Silicic acid showed its most effectivity for maintaining dispersion at a pH range of 4 to 6. Beyond this pH range, dispersion was either strongly favored or prevented, and the effect of silicic acid on dispersion was obscured. Given the ubiquitous presence of silicic acid in soils, our findings regarding its impact on aggregation stability have important implication for conservation of acidic soils.
Keywords
- Dispersion, Kaolinitic soil, Light scattering, Silicic acid, Zeta potential
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Soil Science
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In: Geoderma, Vol. 286, 15.01.2017, p. 8-14.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Silicic acid as a dispersibility enhancer in a Fe-oxide-rich kaolinitic soil clay
AU - Nguyen, Minh N.
AU - Picardal, Flynn
AU - Dultz, Stefan
AU - Dam, Than T.N.
AU - Nguyen, Anh V.
AU - Nguyen, Khai M.
N1 - Publisher Copyright: © 2016 Elsevier B.V. Copyright: Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2017/1/15
Y1 - 2017/1/15
N2 - In soils, dispersion is a crucial step preceding the loss of clay-sized particles by surface run-off and leaching, which in turn results in soil degradation. Despite the fact that silicic acid is common in soil solutions, its effect on aggregation stability of fine sized particles in soils has not been detailed. Here we examined the effect of silicic acid on dispersion of a kaolinitic soil clay fraction rich in Fe-oxides (8.5%) at different pH values by combining dynamic light scattering for particle sizing and test tube experiments for examination of particles in suspension. Adsorption of silicic acid on the clay fraction was characterized by batch adsorption experiments and effects on surface charge by zeta potential (ζ) measurements over a pH range from 2 to 11. We found that silicic acid adsorbed onto clay and co-existing Fe oxides, made ζ more negative, and thereby counteracted aggregation of the clay fraction. Silicic acid showed its most effectivity for maintaining dispersion at a pH range of 4 to 6. Beyond this pH range, dispersion was either strongly favored or prevented, and the effect of silicic acid on dispersion was obscured. Given the ubiquitous presence of silicic acid in soils, our findings regarding its impact on aggregation stability have important implication for conservation of acidic soils.
AB - In soils, dispersion is a crucial step preceding the loss of clay-sized particles by surface run-off and leaching, which in turn results in soil degradation. Despite the fact that silicic acid is common in soil solutions, its effect on aggregation stability of fine sized particles in soils has not been detailed. Here we examined the effect of silicic acid on dispersion of a kaolinitic soil clay fraction rich in Fe-oxides (8.5%) at different pH values by combining dynamic light scattering for particle sizing and test tube experiments for examination of particles in suspension. Adsorption of silicic acid on the clay fraction was characterized by batch adsorption experiments and effects on surface charge by zeta potential (ζ) measurements over a pH range from 2 to 11. We found that silicic acid adsorbed onto clay and co-existing Fe oxides, made ζ more negative, and thereby counteracted aggregation of the clay fraction. Silicic acid showed its most effectivity for maintaining dispersion at a pH range of 4 to 6. Beyond this pH range, dispersion was either strongly favored or prevented, and the effect of silicic acid on dispersion was obscured. Given the ubiquitous presence of silicic acid in soils, our findings regarding its impact on aggregation stability have important implication for conservation of acidic soils.
KW - Dispersion
KW - Kaolinitic soil
KW - Light scattering
KW - Silicic acid
KW - Zeta potential
UR - http://www.scopus.com/inward/record.url?scp=84993116297&partnerID=8YFLogxK
U2 - 10.1016/j.geoderma.2016.10.029
DO - 10.1016/j.geoderma.2016.10.029
M3 - Article
AN - SCOPUS:84993116297
VL - 286
SP - 8
EP - 14
JO - Geoderma
JF - Geoderma
SN - 0016-7061
ER -