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

Equilibrium sorption of phenanthrene in the presence of naphthalene as the background organic solute was measured for the original Chelsea soil and humic acid (HA) and particulate kerogen and black carbon (KB) fractions isolated from the soil. The phenanthrene sorption isotherms measured for both the original soil and the KB fraction became more linear with lower sorption capacity as a function of naphthalene concentration, indicating the significant competitive effect of naphthalene on the equilibrium sorption of phenanthrene. The HA fraction showed a measurable competitive effect only when naphthalene was at a higher concentration level of naphthalene. The particulate organic matter dominated the overall nonlinear and competitive sorption phenomena exhibited by the bulk soil. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA 8/22-26/2004).