engleski

Voltammetric analysis of organic surface active substances in the aquatic environment

Surface active substances (SAS) as constituents of dissolved organic carbon (DOC) as well as particulate organic carbon (POC), were studied in the water samples from different environmental compartments (urban atmosphere, sea- and freshwater systems, soil from agriculture area, and mining water.Investigation was performed byelectrochemical methods - voltammetric techniques, simple, rapid and nondestructive, that were developed by our groupfor rough physicochemical characterization of DOC in the natural waters [1and references therein]. In the biogeochemical processes in aquatic environment, the physicochemical properties of organic matter (OM) are often more important than the amount present. Surface SAS are concentrated by adsorption processes at the natural phase boundaries where they greatly affect transfer of mass and energy.The most analasis techniques are not sensitive to the interface and simply treat the surface as the part of the bulk. Electrochemical method that has been applied since 1970 enables quantification of SAS and offers insight into its spatial distribution and seasonal variations in the water environment while curve shape analysis enables rough characterization of predominant SAS groups.Adsorption effect of SAS from samples was measured at the hanging mercury drop electrode (HMDE) using phase sensitive alternating current voltammetry (PSACV) out-of-phase mode. The permeability of organic film of SAS was tested by the investigation of the influence of the adsorbed layer on the electrode processes of Cd2+ ion which is used as electrochemical tool (PSACV in-phase mode). On that way a rough characterization of OM in natural water samples have been performed using different model substances selected as the major types of DOC in the relevant aquatic systems.

Voltammetric analysis ; surface active substances ; electrochemical method

nije evidentirano