Speciation of Manganese in Natural Waters Using Differential Pulse Stripping Voltammetry in Correlation with Physico-chemical Parameters

To understand the bio-geochemical distribution, activities and environmental consequences of heavy metals, it is very important to know their physico-chemical form and the conditions under which the transformation from one form to another occurs. The bioavailability of heavy metals directly depends on the physico-chemical conditions of the environment, the concentration of anions and cations in water, the content of heavy metals as well as the ionic strength. Depending on the physico-chemical properties of water, metals are found in water as free ions or as complex compounds. Their change in the form in which metals occur is significantly influenced by pH, temperature, alkalinity, water hardness, organic matter, and biological activity. The total concentration of metal in water is only an indicator of pollution, and it is necessary to determine the form of the metal. Differential Pulse Anode Stripping Voltammery with mercury electrode was used for determination of chemical speciation. Manganese belongs to the group of essential heavy metals if its concentration does not exceed the maximum allowed value.

The aim of this work is to determine the available forms of manganese in the water of Modrac Lake in relation to the analyzed physico-chemical parameters. In addition to industrial applications, Modrac Lake is also used as an alternative source of drinking water, and it is a strategic resource for water supply of the region of north-eastern Bosnia.