Exploring the Role of Surface Characteristics in Determining Sorption Properties of Chars and Soots

Johns Hopkins University, Baltimore MD

Investigators

Abstract

0332160 Ball Objectives of the proposed work are to evaluate the extent and nature of HOC sorption in wood char and soot particles; to carefully characterize salient physical and chemical properties of the sorbents and to use this information to test specific hypotheses regarding the role of internal surface structure, surface chemistry, and authigenic (natively bound) polycyclic aromatic hydrocarbons [PAHs] in controlling sorption for HOCs. The work will include studies with selected soots and chars of the following types: (1) natural chars obtained from burnt pine logs at sites of controlled burn; (2) synthetic chars formed from the same wood source at different final temperatures of carbonization; (3) diesel soot reference materials from NIST; (4) laboratory-generated hexane soot; and (5) chemically modified selected chars and soots with well-controlled differences in surface characteristics. Most sorption studies will be performed with two sorbates (1,2,4-trichlorobenzene and 2,4-dichlorophenol). Experiments with these and other sorbates will elucidate the role of sorbate structure on specific aspects of sorption, including p.p bonding as well as dipole-dipole and hydrogen-bonding interactions with surface oxides.