Contact Information Correction
The contact details of the author Alidor Shikika have been updated.
Text Correction
The original publication [1] contained a typographical error in the XRD data collection description (radiation source wavelength), and a mistake in the XRD data itself (ABF/ore mass ratio of 3/1) due to a copy–paste error.
A correction has been made to Section 2. Materials and Methods, Subsection 2.2. Ore Characterization, second paragraph:
The mineral-phase analysis of the ore was carried out by an X-ray Bruker D8-ECO diffractometer with CuKα radiation (λ = 1.54 Å). The sample was pulverized before being scanned between 3 and 90°2θ at a rate of 0.02°2θ per second.
Error in Figure
In the original publication, there was a mistake in Figure 13 as published. The XRD pattern (b) corresponding to the ABF/ore mass ratio of 3/1 was incorrectly plotted when importing data from the XY file, leading to data misrepresentation. The corrected Figure 13 appears below.
Figure 13.
XRD patterns of the raw coltan ore (a) and residues from fluorination and acid leaching at 200 °C for 2.5 h at ABF/ore ratios of 3/1 (b) and 5/1 (c).
The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.
Reference
- Shikika, A.; Zabene, F.; Muvundja, F.; Mugumaoderha, M.C.; Colaux, J.L.; Aatach, M.; Gaydardzhiev, S. Extraction of Ta and Nb from a Coltan Bearing Ore by Means of Ammonium Bifluoride Fluorination and Sulfuric Acid Leaching. Minerals 2021, 11, 1392. [Google Scholar] [CrossRef]
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