Analysis of Asbestos in Bulk Materials by X-Ray Diffraction: Influence of Grinding Methods on the Result

Abstract

The grinding method for sample preparation affects the results of X-ray diffraction analysis of minerals, mainly the soft and inelastic components of raw materials and synthetic matrices. This fact is determined by a “disturbance” of crystal order in the surface layer of particles and is more pronounced when a fine comminution is performed and when a high shearing stress is applied in grinding. This effect is remarkable on asbestos minerals.
Subsequent to some information on the development of the science of “mechanochemistry”, this paper reports the results of several tests on single, binary and polygenic materials containing chrysotile and crocidolite under different grinding conditions (type of mill and grinding time). The aim of the research is to give suggestions about a sample preparation methodology for XRD quantitative determination of asbestos in bulk materials, suitable for obtaining more accurate results.