A fundamental study of a novel dynamic electrochemical technique for the measurement of trace amounts of arsenic and antimony in molten zinc

Various electrochemical experiments were performed involving the electroche mical introduction of sodium atoms into molten zinc using sodium beta " -al umina electrolyte in an attempt to measure the concentration of dissolved a rsenic and antimony in zinc by these dynamic techniques. Under high rates o f sodium injection, the formation of the intermetallic phase NaZn13 was ded uced from intermittent galvanostatic polarisation with the value DeltaG(f)( o)(NaZn13) = - 48 kJ mol(-1) derived at 788 K. Under more moderate injectio n rates employing a symmetric 'zinc/zinc cell' configuration, a qualitative relationship between the current generated during cyclic voltammetry and t he arsenic and antimony concentrations in molten zinc was observed. (C) 200 0 Elsevier Science B.V. All rights reserved.