POLARIZATION CHARACTERISTICS OF DSA ANODES IN THE CONDITIONS OF OBTAINING SODIUM-CHLORATE

Polarization measurements under galvanostatic conditions in the chlori de-chlorate solutions of various compositions conducted at different p H and temperatures demonstrate that the critical potential E-cr at cur rent densities below 0.7 A/cm(2) is attained in the solutions with NaC l concentrations of 50 g/l and lower. The conditions increasing the ri sk that the potential will exceed E-cr are low temperatures (about 60 degrees C), pH above 6.5, and the chromate additive concentration exce eding 2 g/l. A simultaneous decrease in the anodic potential, in spite of a decrease in E-cr with the increasing temperature, allows the ele ctrolysis to be performed at elevated temperatures and current densiti es without the risk that the potential will exceed E-cr mechanism of t he potential transition into the supercritical region is discussed on the basis of a ruthenium-water system.