3: X-ray Fluorescence Spectrometry Check Access

This chapter covers the use of XRF spectrometry. A very brief introduction to the theory is given followed by a summary of the capabilities of wavelength and energy dispersive instruments. A discussion of physical and spectral interferences is then provided. The largest section of the chapter covers the methods of sample preparation. This includes the analysis of liquids and solid materials. For the solid materials, the three main preparation methods of loose powder, pressed pellet and fused glass disk were all discussed, giving the potential errors involved and the advantages and disadvantages of each. For the fused glass disks, mention is also made of the requirement for the maintenance of the platinum ware. Methods of cleaning and minimising damage are presented. A section on XRF analysis covers the use of in-built calibrations and external calibration, picking wavelengths/energies to measure, etc. A brief explanation of chemical interferences is also provided. The final part of the chapter discusses the relative merits and capabilities of portable XRF instruments. Again, their advantages and disadvantages were given along with some hints and tips to try and minimise problems associated with calibration and obtaining the “correct” result.