The Impedance Analysis of Reaction Kinetics at the Interface between Molten Sn–S Alloy and ZnCl₂–NaCl Salt

Abstract

The interfacial reaction between molten Sn–S alloy and ZnCl₂-NaCl salt was studied by an A. C. impedance method to clarify the individual kinetic factors concerning the electrode reaction at the interface between the alloy and the salt. The total impedance between Sn–S alloy and ZnCl₂–NaCl salt was measured.
The results obtained were successfully used to determine the individual kinetic factors on electrode reaction between the alloy and the salt, such as electrolyte resistance R_e, double-layer capacitance C_d, charge transfer resistance R_ct, rate constant of desulfurization reaction k_f and so on. When overpotential η equals to –85 mV, these values are as follows: R_e=2.93×10^–5 Ωm², R_ct=2.47×10^–5 Ωm², C_d=1.01 Fm^–2, k_f=2.1×10^–3 s^–1.