Reusable adsorbents for dilute solution separation. 4: Adsorption of 1,2 dichlorobenzene and phenanthrene on a surfactant-modified semiconductor (titania) surface

The surface of a semi-conducting surface, viz., titania was modified by ads orbing an anionic surfactant, viz., sodium dodecyl sulfate (SDS) at aqueous pH values less than the point of zero charge of 6.8. The hydrophobic titan ia surface was capable of adsorbing hydrophobic organic compounds, such as 1,2-dichlorobenzene and phenanthrene at dilute concentrations from the aque ous phase. The adsorption partition coefficients for both compounds on SDS hemi-micelles on TiO2 are of magnitudes similar to their octanol-water part ition constants, which are indicators of similar hydrophobic environments. The potential uses of SDS-coated TiO2 for simultaneously adsorbing and phot o-chemically degrading hydrophobic organic compounds as a means of treating dilute wastewater streams are suggested. (C) 2000 Elsevier Science B.V. Al l rights reserved.