ON THE DISSOLUTION OF PYRRHOTITE:IN-SITU ELECTROCHEMICAL ANALYSIS OF SURFACE LAYERS

摘要

The anodic dissolution of pyrrhotite in 1M HC1 electrolyte has been studied by in-situ Mott-Schottky analysis of the formed surface layers. It was observed that, depending on the electrode potential, two distinct n-type semiconductor surface layers were formed on the electrode which hindered the dissolution rate of the mineral. Potentiodynamic testing was applied to support the data in the Mott-Schottky plots. The formation of a thick and uniform layer on the surface of the mineral was observed by SEM and the composition of the surface film was determined to be 98% sulfur and 2% iron by EDX analysis.