Investigation of Radiological and Chemical Contents of Bauxite Ore Extracted in Turkey

Abstract

In this study, which consists of two parts, the radiological and chemical content of bauxite ore was investigated. Gamma-ray spectrometry was used in the first part of the study to determine the activity concentrations of natural radionuclides in samples taken from bauxite deposits in Turkey. The measured activity concentrations of 226Ra, 232Th, and 40K varied from 12.1 ± 2.5 to 132.6 ± 11.4 Bq kg–1 with a mean of 78.4 ± 8.3 Bq kg–1, 6.5 ± 0.5 to 97.3 ± 9.9 Bq kg–1 with a mean of 64.5 ± 5.9 Bq kg–1, and 5.1 ± 0.0 to 356.4 ± 40.1 Bq kg–1 with a mean of 52.6 ± 5 Bq kg–1, respectively. The calculated mean radium equivalent activity value is 177.4 Bq kg–1, the mean gamma dose rate absorbed in the air is 78.8 nGy h–1, the mean corresponding annual effective dose value is 96.6 μSv y–1, and the mean lifetime risk of cancer is 3.85 × 10–4. The chemical content of the bauxite samples was determined in the second part of the study using X-ray fluorescence spectrometry (XRF). For which sectors in the industry the existing bauxite deposits in Turkey can be used was investigated based on this information.

New Approach to Determine the Activity Concentration Index in Cements, Fly Ashes, and Slags on the Basis of Their Chemical Composition

“…The increase in the natural radionuclide content, with respect to OPC-type cements, would therefore be related to the presence of bauxite in the manufacturing process. Bauxites have a high content of radionuclides belonging to the radioactive thorium and uranium series, but not as high as 40 K, which is consistent with the grouping shown in the HJ–Biplot ( Figure 3 ) [ 76 ]. The 40 K exhibited the expected behavior as it correlated with K 2 O and Na 2 O.…”

Assessment of the Levels of Potentially Toxic Elements Contained in Natural Bentonites Collected from Quarries in Turkey

“…Interference in the X-ray peak in the spectrum can be easily corrected, thus ensuring high accuracy and sensitivity easily. EDXRF and wavelength-dispersive XRF spectroscopy are used for qualitative and quantitative multi-element analysis of major, minor, and trace elements in archeological, geological, biological, industrial, food, and environmental samples and require minimal sample preparation. ,− The analysis of PTEs in the bentonite samples was performed with the help of the EDXRF spectrometer (Spectro Xepos, Ametek). The EDXRF spectrometer is equipped with an anode X-ray tube (50 W, 60 kV) consisting of a dual thick Pd/Co mixture. ,,,, The EDXRF spectrometer’s target modifier, which optimizes excitation by using polarization and secondary targets, has many different excitation conditions that guarantee the best detection of all elements from Na to U.…”