TY - JOUR
T1 - Retention behavior of hydrophobic organic chemicals as a function of temperature in soil leaching column chromatography
AU - Liang, Xinmiao
AU - Xu, Feng
AU - Lin, Bingcheng
AU - Su, Fan
AU - Schramm, Karl Werner
AU - Kettrup, Antonius
PY - 2002/11
Y1 - 2002/11
N2 - To study the transport mechanism of hydrophobic organic chemicals (HOCs) and the energy change in soil/solvent system, a soil leaching column chromatographic (SLCC) experiment at an environmental temperature range of 20-40 °C was carried out, which utilized a reference soil (SP 14696) packed column and a methanol-water (1:4 by volume ratio) eluent. The transport process quickens with the increase of column temperature. The ratio of retention factors at 30 and 40 °C (k′30/k′40) ranged from 1.08 to 1.36. The lower enthalpy change of the solute transfer in SLCC (from eluent to soil) than in conventional reversed-phase liquid chromatography (e.g., from eluent to C18) is consistent with the hypothesis that HOCs were dominantly and physically partitioned between solvent and soil. The results were also verified by the linear solvation energy relationships analysis. The chief factor controlling the retention was found to be the solute solvophobic partition, and the second important factor was the solute hydrogen-bond basicity, while the least important factors were the solute polarizability-dipolarity and hydrogen-bond acidity. With the increase of temperature, the contributions of the solute solvophobic partition and hydrogen-bond basicity gradually decrease, and the latter decreases faster than the former.
AB - To study the transport mechanism of hydrophobic organic chemicals (HOCs) and the energy change in soil/solvent system, a soil leaching column chromatographic (SLCC) experiment at an environmental temperature range of 20-40 °C was carried out, which utilized a reference soil (SP 14696) packed column and a methanol-water (1:4 by volume ratio) eluent. The transport process quickens with the increase of column temperature. The ratio of retention factors at 30 and 40 °C (k′30/k′40) ranged from 1.08 to 1.36. The lower enthalpy change of the solute transfer in SLCC (from eluent to soil) than in conventional reversed-phase liquid chromatography (e.g., from eluent to C18) is consistent with the hypothesis that HOCs were dominantly and physically partitioned between solvent and soil. The results were also verified by the linear solvation energy relationships analysis. The chief factor controlling the retention was found to be the solute solvophobic partition, and the second important factor was the solute hydrogen-bond basicity, while the least important factors were the solute polarizability-dipolarity and hydrogen-bond acidity. With the increase of temperature, the contributions of the solute solvophobic partition and hydrogen-bond basicity gradually decrease, and the latter decreases faster than the former.
KW - Enthalpy
KW - Linear solvation energy relationships
KW - Retention factor
KW - Soil leaching column chromatography
KW - Temperature
UR - http://www.scopus.com/inward/record.url?scp=0036827204&partnerID=8YFLogxK
U2 - 10.1016/S0045-6535(02)00308-9
DO - 10.1016/S0045-6535(02)00308-9
M3 - Article
C2 - 12430644
AN - SCOPUS:0036827204
SN - 0045-6535
VL - 49
SP - 569
EP - 574
JO - Chemosphere
JF - Chemosphere
IS - 6
ER -