Nonequilibrium sorption of dimethylphthalate - Compatibility of batch and column techniques

This study reconciles an apparent inconsistency between the dimethylphthala te (DMP) batch and column data reported in the literature. Some researchers found that retardation coefficients obtained by fitting a linear two-stage model to column data were about 50% smaller than those calculated from the distribution coefficient of a 14-d isotherm. In this study, sorption param eters were derived independently by fitting a linear and a nonlinear two-st age model simultaneously to the 3- and 14-d isotherms as well as to a sorpt ion rate study reported by others. With the sorption parameters and the dis persion coefficient obtained from a tritium tracer experiment, the column d ata were adequately predicted. A major part of the differences in the retar dation coefficients observed in other research could be related to experime ntal difficulties in detecting the tailing of nonequilibrium breakthrough c urves.