Physico-chemical and Mineralogical Characterization of Coltan Ores from the Tanganyika Province in the Democratic Republic of Congo

Abstract

The physico-chemical, mineralogical, and radioactive characterization of coltan ores has the ad-vantage of facilitating the prediction of the various hydrometallurgical methods to be implemented to pro-duce tantalum and niobium in their pure state, taking into account the content of their oxides and that of accompanying impurities. At the end of this investigation, we noted that the coltan ores collected from the four mining sites in Tanganyika province did not have the same mineralogy or the same chemical composition in terms of tantalum and niobium oxides and accompanying impurities. These ores contain a mineralogy that looks like either struëverite, euxènite, colombo-tantalite or tantalite. Moreover, the coltan from this province presented no risk of exposure to ionizing radiation, given the radioactivity values found by the dosimeter and whose average value in milli-Sieverts per year remained well below the threshold set in the regulations in force in DR Congo. We found an average value of 0.143 mSv/year versus 20 mSv/year featured in the law of March 29, 2005, and promulgated in the official gazette of country.