Determination of preferential adsorption of Depramin® on mineral surfaces by ToF-SIMS

Selective adsorption of mining chemicals on specific ore minerals is desirable for efficient flotation. This paper reports on a feasibility study to localise and visualise the distribution of Depramin®, a polymeric depressant, produced by Akzo Nobel on a real ore at realistic depressant loadings. The combined use of bulk and micro-analytical techniques has been very useful. Bulk mineralogy determination by XRD can be correlated with data obtained by the well-developed SEM/EDX technique for local quantitative mineral classification. Starting from that basis, the potential of local mineral classification by the less established, surface sensitive, technique ToF-SIMS has been demonstrated. Although this is a qualitative analysis technique, in addition to mineral classification, ToF-SIMS is also able to identify depressants locally on ore phases at realistic bulk concentrations. Bulk depletion analysis results serve to “quantify” the surface analytical ToF-SIMS spectra. Supporting advanced data analysis tools, including principal component analysis (PCA) and spectral image processing, are important for the analysis of the correlation between data obtained from different techniques.