Abstract
Among the most used techniques for heavy metal detection in metallurgic industry are atomic absorption (AAS) and Inductively Coupled Plasma - Mass Spectroscopy (ICP-MS). However these techniques are expensive and time consuming, and even more important, they are not suitable for online and in situ use. Voltammetry is a fast and inexpensive electrochemical technique. Contrary to most other methods, it is possible to construct voltammetric apparatus for online and remote monitoring, with sensitivity for many important heavy metals in the ppt range. Also voltammetry renders the possibility for speciation studies and to identify specific oxidation states of metals. In the present work voltammetric procedures using non-toxic electrode materials for online analyses of heavy metals like nickel, cobalt, zinc, cadmium, and lead, in waste and process water from metallurgical nickel industry have been worked out. Environmentally friendly electrodes like solid dental amalgam, silver, silver-alloys, gold and glassy carbon electrodes have been evaluated. In this work, the use of anodic as well as cathodic stripping voltammetry, of interest for measurements of wastewater in metallurgical nickel industry, will be discussed.