Dirk Wissmann

New excitation developments and advanced detector technology enable the use of EDXRF for multielement analysis of plant material and fertilizers, with improved detection limits and reduced measurement time. These features are combined with easy sample preparation and low cost of investment.

The EDXRF method described here is a quick and economical procedure to check samples for their oxygen content to ensure that the material used for diesel fuel blending is really FAME-based and not mineral-oil based.

This month’s column will describe a novel ED-XRF system, which utilizes a combination of a Bragg polarizer, used simultaneously with a direct excitation source, together with a novel, highly annealed pyrolytic graphite (HAPG) crystal as a band-pass filter. By selection of the optimum configuration, it will allow for high precision of minor and major elements across a wide wavelength range and/or lower detection capability for smaller groups of elements from potassium to manganese. To show the practical benefits of this technology, this study will focus on these performance metrics for the determination of titanium in polymer samples, together with the multielement analysis of high purity graphite using the ashing sample preparation method. In particular, it will be shown that the improved performance for graphite will allow for lower sample weights to be used resulting in significantly shorter ashing times, which is a requirement for high sample workload laboratories and process control applications.