A comparative study on detection of organic surface modifiers on mineral grains by TOF-SIMS, VUV SALI TOF-SIMS and VUV SALI with laser desorption

Results from a comparative study on the detection of organic collectors by TOF-SIMS, vacuum ultraviolet surface analysis by laser ionization with TOF-SIMS detection (VUV SALI TOF-SIMS) and VUV SALI with laser desorption (VUV TOF-LIMS) are reported. The study was carried out on a PHI 7200 TOF-SIMS instrument upgraded with two lasers: one for laser desorption and another one for VUV laser postionization. A systematic analysis of the laser desorption process lead to a set of optimized desorption parameters and desorption of molecules with a controlled level of fragmentation. The recorded spectra of organic collectors by VUV SALI with laser desorption are characterized by strong parent peaks and simpler fragmentation patterns, which allow for easy molecular identification. Advantages and limitations of the three techniques for analysis of organic collectors on mineral grains are discussed. # 2004 Elsevier B.V. All rights reserved