Characterization of diatomaceous earth from Kolubara mining basin, Serbia

Abstract

Diatomaceous earth is of sedimentary origin consists mainly of accumulated skeletons formed as a protective covering of the diatoms. Usually, high absorption capacity of diatomaceous earth provides its wide use as heat insulation, filter, and absorbent material. Starting raw material, diatomaceous earth from surface coal mine Kolubara, Serbia, was characterized using X-ray fluoroscence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) were employed to the phases and microstructure of the diatomaceous earth. In addition, concentrations of activity of natural radionuclides 40K, 226Ra and 232Th and anthropogenic radionuclide 137Cs in diatomaceous earth were determined by gamma spectrometry with HPGe detector. It was found that the activity concentrations were in the range of 150-190 Bq / kg for 40K, 5-12 Bq / kg for 226Ra and 22-33 Bk / kg for 232Th. In all samples, the concentration of anthropogenic radionuclide 137Cs was below the detection limit. This research shows that this material is environmentally safe for further use.