Interaction of β-Cyclodextrin with Lipophilic Ring Compounds Deposited in a Sandy Soil Matrix during Flushing

摘要

Chemical soil flushing in a packed sandy soil matrix using a natural surfactant, β-cyclodextrin (CD) was investigated via a fluorescence spectroscopy and a dye labeling. The contaminants are lipophilic ring compounds -phenanthrene and naphthalene. Sand type and flushing intensity (rate and concentration) are critical investigation variables. The removal efficiencies were proportional to flow rate, concentration, temperature of the flushing solution and voidity of the sand column. Initial sorption of the surfactant onto the soil matrix was found to be a key step while flow shear was more crucial in the later steps. From time delay experiments before flushing, we speculate that the com-plexation reaction appears to be rate-limiting in non-equilibrium washing schemes.