In situ FTIR study of ethyl xanthate adsorption on gold, silver and copper electrodes under controlled potential

The applicability of a spectroelectrochemical method to the problems related to flotation was studied. The object of the study was to investigate the adsorption of ethyl xanthate on gold, silver and copper surfaces. Spectra were obtained using subtractively normalized interfacial Fourier transform infrared spectroscopy, which allows potential control of electrode while recording an infrared spectrum at the electrode surface. For each metal, a good correlation exists between the spectral intensities of the product of the surface reaction and the voltammogram of the metal electrode immersed in xanthate solution. On gold, xanthate is oxidized to dixanthogen, which is then adsorbed onto the gold surface. In the case of both silver and copper, xanthate reacts with the surface in two separate steps. The first comprises chemisorption of xanthate, the result being a monolayer of metal xanthate‐like surface compound. The second, more anodic, step is the formation of multilayers of metal xanthate.