Role of particulate organic matter in the competitive sorption between phenanthrene and naphthalene on Chelsea soil

Mixtures of different hazardous organic chemicals are commonly found in contaminated sites and surface aquatic and groundwater systems. Equilibrium sorption of a binary system consisting of phenanthrene and naphthalene by topsoil and the soil organic matter fractions isolated from the soil was studied. The isolated kerogen and black carbon fraction exhibited significantly reduced sorption capacity and isotherm nonlinearity for phenanthrene as the primary solute and naphthalene as the background solute while the humic acid fraction showed little competitive effect. The topsoil was collected from Chelsea, MI. The phenanthrene sorption isotherms measured for both the original soil and the KB fraction became more linear with lower sorption capacity as the background naphthalene increased, indicating significant competitive effect of naphthalene on the equilibrium sorption of phenanthrene. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA 8/22-26/2004).