Comparison of methods for the deposition of polycyclic aromatic hydrocarbons on the surface of coal stack ash

Two methods for the deposition of organic pollutants on the surface of environmental particulates are compared: the common slurry-spike method and a method presented herein termed the ''suspension method.'' Higher extraction efficiencies resulting from the slury-spike method indicated that the slurry-spike method forced the adsorption of polycyclic aromatic hydrocarbons (PAHs) on the weaker binding sites. Also, with the suspension method, it was shown that the resulting surface concentration of PAHs on coal stack ash can be controlled by adjusting the solution concentration of the PAHs. (C) 1997 Elsevier Science Ltd.