The application of isotachophoresis to the compost analysis

The paper presents the results of determination of selected heavy metals (Cu, Cd, Cr and Ni) and selected organic acids (formic, lactic, acetic and propionic) in sewage sludge from the Waste Water Treatment Plant (WWTP) in Torun, and in compost prepared from that sludge. The conditions of the organic acid extraction (the time and the temperature) and wet digestion method for the heavy metals determination were optimised. The results for the heavy metals obtained from isotachophoresis (ITP) were compared with those provided by atomic absorption spectroscopy. The classical acidimetric titration was used as the reference method for the determination of organic acid. The determination of selected inorganic anions, i.e. chlorides, sulfates and nitrates in aqueous compost extracts has been also investigated with the capillary zone electrophoresis (CZE) as the reference method.