Abstract
Some of the problems associated with the application of the existing thermodynamics of ion exchange for the description of ion adsorption on variable charge soils are discussed. A major problem is the difficulty in saturating the surface functional groups of variable charge materials with ions other than H+ or OH−, i.e., the difficulty in obtaining complete exchange isotherms. It was shown that this difficulty could be overcome by choosing appropreate standard states of exchanger phase components. A set of equations that relate the exchanger phase activity coefficients and thermodynamic equilibrium constant to the selectivity coefficient were derived based on a nonconventional asymmetric reference system. The terms related to adsorbed water activity that appear in the derived equations were found to be non-significant for some variable charge materials.
| Original language | English |
|---|---|
| Pages (from-to) | 191-200 |
| Number of pages | 10 |
| Journal | Soil Science and Plant Nutrition |
| Volume | 37 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Jun 1991 |
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All Science Journal Classification (ASJC) codes
- Soil Science
- Plant Science
Cite this
Ion adsorption on variable charge materials and thermodynamics of ion exchange. / Wada, Shin Ichiro; Kawabata, Kouya; Kawabata, Kouya.
In: Soil Science and Plant Nutrition, Vol. 37, No. 2, 06.1991, p. 191-200.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Ion adsorption on variable charge materials and thermodynamics of ion exchange
AU - Wada, Shin Ichiro
AU - Kawabata, Kouya
AU - Kawabata, Kouya
PY - 1991/6
Y1 - 1991/6
N2 - Some of the problems associated with the application of the existing thermodynamics of ion exchange for the description of ion adsorption on variable charge soils are discussed. A major problem is the difficulty in saturating the surface functional groups of variable charge materials with ions other than H+ or OH−, i.e., the difficulty in obtaining complete exchange isotherms. It was shown that this difficulty could be overcome by choosing appropreate standard states of exchanger phase components. A set of equations that relate the exchanger phase activity coefficients and thermodynamic equilibrium constant to the selectivity coefficient were derived based on a nonconventional asymmetric reference system. The terms related to adsorbed water activity that appear in the derived equations were found to be non-significant for some variable charge materials.
AB - Some of the problems associated with the application of the existing thermodynamics of ion exchange for the description of ion adsorption on variable charge soils are discussed. A major problem is the difficulty in saturating the surface functional groups of variable charge materials with ions other than H+ or OH−, i.e., the difficulty in obtaining complete exchange isotherms. It was shown that this difficulty could be overcome by choosing appropreate standard states of exchanger phase components. A set of equations that relate the exchanger phase activity coefficients and thermodynamic equilibrium constant to the selectivity coefficient were derived based on a nonconventional asymmetric reference system. The terms related to adsorbed water activity that appear in the derived equations were found to be non-significant for some variable charge materials.
UR - http://www.scopus.com/inward/record.url?scp=0009840818&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0009840818&partnerID=8YFLogxK
U2 - 10.1080/00380768.1991.10415029
DO - 10.1080/00380768.1991.10415029
M3 - Article
AN - SCOPUS:0009840818
VL - 37
SP - 191
EP - 200
JO - Soil Science and Plant Nutrition
JF - Soil Science and Plant Nutrition
SN - 0038-0768
IS - 2
ER -