Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

We present a new approach to 3-dimensional chemical imaging based on computed tomography (CT), which allows a reconstruction of the internal elemental chemistry. The method uses a conventional laboratory based CT scanner combined with a semiconductor detector (CdTe). Based on the X-ray absorption spectrum, elements in a sample can be distinguished by their K-edge energy, which is specific. Different experiments have been preformed to test the performance of the system i.e. single pure element particle measurements, element differentiation in mixtures, and mineral differentiation in a gold ore sample. The results show that the method is able to distinguish elements in the samples with K-edges in the range of 20 to 160 keV, which corresponds to an elemental range from Ag to U. Furthermore, the spectral information allows a distinction between materials, which show no variation in contrast in the reconstructed CT image.