Assessment of the relations between the spectroscopic characteristics of soils and their ability to adsorb organic pollutants

The aim of this research was to study the way the humus content of the soils affects the adsorption of particular organic pollutants. We used five different media during the experiments: two different soils (sandy soil, coherent soil), humic acid extracts extracted from these soils, and a commercially available humic acid product. We studied the adsorbed amount of the given compounds at the particular media, the role of humic materials in the observed adsorption ratios, and whether the co-existence of the different compound changes the adsorption-desorption conditions. The inorganic components of the soils play an important role also in the absorption of the apolar compounds, and as the polarity (or polarizability) of the organic compound increases, the humic materials of the soil, or rather their polar functional groups take the dominant role in the absorption of the pollutant. The absorption and desorption of three apolar compounds were practically not influenced by the presence of other pollutants in the soil, and this phenomenon was also independent from the extracting agent. However, in the case of polar diuron, the presence of other pollutants can result in decrease of mobility. (C) 2004 Elsevier B.V. All rights reserved.