In-Situ Internal Reflection Spectroscopy for the Study of Surfactant Adsorption Reactions Using Reactive Internal Reflection Elements

Abstract

Abstract Infrared spectroscopy has been one of the most useful experimental techniques for the analysis of surface reactions. In particular, Fourier transform infrared (FTIR)/internal reflection spectroscopy (IRS) is most often used for in-situ studies. To date, three FTIR/IRS methods have been used for in-situ measurements. These techniques are evaluated for use in the characterization of surface reactions common to flotation systems. The method which uses mineral crystals as reactive internal reflection elements (IREs) is of particular interest because it allows surfactant adsorption densities to be calculated directly from in-situ spectral data in real time, and is the focus of this paper. Application of in-situ FTIR/IRS with reactive IREs is demonstrated for collector adsorption reactions in each of the four major flotation systems. Also, the use of reactive IREs in the near-IR spectral region and in spectroelec-trochemical research is discussed.