Development of a platinum rotating disc electrode for dynamic electrochemical measurements in glass melts

A configuration is described and tested that enables electrochemical measur ements at a rotating disc electrode in glass melt environments. In a glass melt with 10 mass% Fe2O3 at 1200 degreesC, it was possible to reach a time independent steady-state current, through rotating the electrode. In aqueou s solutions, time independent electrode signals show distinct advantages to study the oxidation-reduction behaviour and the properties of polyvalent e lements. The influence of rotation rate was studied and the results obtaine d were compared with those obtained at a static disc electrode. The rotatio n speed dependence of the steady-state current obtained in a molten glass e nvironment at 1200 degreesC was shown to obey the Levich-equation. An expec ted advantage of time independent signals is the concentration determinatio n of metal ions in glass melts continuously and online. This opens new pers pectives concerning the online monitoring and automatic control of the glas s production processes. Furthermore, the validity of the Levich-equation op ens new possibilities for diffusion coefficient measurement of metal ions i n glass melts. (C) 2001 Elsevier Science B.V. All rights reserved.