CHARACTERIZATION AND BENEFICIATION OF LOW GRADE Nb AND Ta ORE FROM KIBARA BELT

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7105-98-8 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 11, 789-796 pp, DOI: 10.5593/sgem2017/11/S04.100

ABSTRACT

Due to their chemical, physical and mechanical properties, niobium (Nb) and tantalum (Ta) are strategically used in various technical applications. About 130 different minerals contain tantalum and niobium, of which only about 80 are found in economical deposits. The remainder contains Nb and Ta as impurities. The most commercialised source of Nb and Ta is a columbite-tantalite ore often referred to as coltan containing pyrochlorite. The Central African Mesoproterozoic Kibara belt in Katanga (Democratic Republic of Congo) forms a metallogenic province that hosts a variety of granite-related mineralization, rich in cassiterite, columbite–tantalite, wolframite/ferberite, spodumene and beryl. This study focuses on the characterization of Nb/Ta ores from the Kibara belt by using the XRF, SEM/EDS, XRD and ICP-OES. It was observed that Nb/Ta ore that occurs in this belt has a high Nb/Ta ratio. The grade of the ore is 0.01wt% Ta and 0.04wt% Nb. The major minerals phases are Tapiolite, Tantalite, Simpsonite, Pyrochlore and Ilmenorutile. The major gangue minerals present locking Nb/Ta are silica, feldspars with small amounts of mica and quartz. The size of the particles containing Nb/Ta are 8-12microns. Basing on these results, flotation is proposed at as the suitable way of concentrating this ore.

Keywords: niobium, tantalum, flotation, Pyrochlore and Kibara belt