ABSTRACT

The sorption of polycyclic aromatic hydrocarbons in aquatic sediments from Zegrzyńskie Lake was examined. Batch experiment was performed in order to determine sorption efficiency in different kinds of sediments from Zegrzyńskie Lake. Five polycyclic aromatic hydrocarbons (phenanthrene, fluoranthene, pyrene, chrysene benzo(ajpyrene) were chosen to this experiment and sorption process was examined on seven sediments of different properties. Chosen hydro­carbons are of different structure of molecule and different chemical and physical properties. Concentrations of polycyclic aromatic hydrocarbons in aquatic sediments and in water phase were measured in the following order: extraction with dichloromethane, concentration on rotary evaporator, silica gel clean up, n-hexane elution, concentration on rotary evaporator and in vials, GC/MS analysis. Chemical composition of aquatic sediments were examined using methods for sewage sludge and soils analysis. In every sediment concentrations of PAHs, organic matter and organic: carbon, phosphorus, nitrogen and sulphur were measured. Also fractional analysis of sediments was made. Isotherms of sorption were measured for these sediments and compounds. Equations of these isotherms were performed and were used in order to find relationships between sorption efficiency and sediments composition. Depending on sediment properties and composition different concentrations of polycyclic aromatic hydrocarbons were found in solid phase. Sediments of high quantities of organic matter and small particles were the best sorbents for PAHs. Fluoranthene, pyrene and chrysene were efficiently sorbed in sediments of high concentration of organic matter. And efficiency of phenanhrene and benzo[a]pyrene sorption were better in sediments with high quantity of organic sulphur.