The determination of soil adsorption coefficients (Km) via HPLC capacity factors (le) has been studied, including the effect of column type and mobile phase composition on the correlation between log K^c and log k'. Koc values obtained by procedures other than HPLC correlate well with HPLC capacity factors determined on a chemically immobilized humic acid stationary phase, and it is suggested that this phase is a better model for the sorption onto soil or sediment than the octadecyl-, phenyl- and ethylsilica phases. By using log kw a theoretical capacity factor has been obtained by extrapolation of the retention data in a binary solvent system to pure aqueous eluent. There is a better correlation between log kqcand log k'w than the correlation between log Koc and log k.
Bibliographical noteFunding Information:
Gy. Szab6 was supported by an International Atomic Energy Agency training fellowship which was held at the National Radiological Protection Board. Part of this work was supported by Bio-Separation Co., Budapest, Hungary.