TY - JOUR
T1 - Application of the Rietveld refinement method for quantification of mineral concentrations in bauxite residues (alumina refining tailings)
AU - Santini, Talitha
PY - 2015/6/10
Y1 - 2015/6/10
N2 - Mineral processing tailings are complex mixtures of minerals residual from the parent ore and minerals formed during processing. The number of minerals present in tailings samples, and their unusual composition and structure compared with minerals naturally occurring at the Earth's surface, poses challenges for quantification of mineral concentrations. Determination of mineral concentrations in tailings can be required to meet legislative requirements, to conduct geochemical modeling, and to optimize mineral processing efficiency. This review compares techniques for quantification of mineral concentrations in bauxite residue (alumina refining tailings), as a case study, and highlights major sources of inaccuracy in quantification methods. Although alternative techniques exist for the quantification of mineral concentrations in bauxite residues, Rietveld refinement-based quantitative phase analysis is likely to be more accurate and precise than methods based on chemical extraction, normative calculation, or single X-ray diffraction peaks. The problems of microabsorption, caused by both heavy and light X-ray absorbing minerals being present in a sample, and non-ideal mineral compositions, such as those of minerals formed during ore processing (desilication product minerals, in the case of bauxite residue), are particularly difficult and impractical to eliminate completely; however, they may be minimized by careful sample preparation and analysis, and further characterization of process characteristic minerals.
AB - Mineral processing tailings are complex mixtures of minerals residual from the parent ore and minerals formed during processing. The number of minerals present in tailings samples, and their unusual composition and structure compared with minerals naturally occurring at the Earth's surface, poses challenges for quantification of mineral concentrations. Determination of mineral concentrations in tailings can be required to meet legislative requirements, to conduct geochemical modeling, and to optimize mineral processing efficiency. This review compares techniques for quantification of mineral concentrations in bauxite residue (alumina refining tailings), as a case study, and highlights major sources of inaccuracy in quantification methods. Although alternative techniques exist for the quantification of mineral concentrations in bauxite residues, Rietveld refinement-based quantitative phase analysis is likely to be more accurate and precise than methods based on chemical extraction, normative calculation, or single X-ray diffraction peaks. The problems of microabsorption, caused by both heavy and light X-ray absorbing minerals being present in a sample, and non-ideal mineral compositions, such as those of minerals formed during ore processing (desilication product minerals, in the case of bauxite residue), are particularly difficult and impractical to eliminate completely; however, they may be minimized by careful sample preparation and analysis, and further characterization of process characteristic minerals.
KW - Environmental mineralogy
KW - Mineral concentrations
KW - Quantitative phase analysis
KW - RIETVELD refinement
KW - Tailings
UR - http://www.scopus.com/inward/record.url?scp=84928479265&partnerID=8YFLogxK
U2 - 10.1016/j.minpro.2015.04.004
DO - 10.1016/j.minpro.2015.04.004
M3 - Article
AN - SCOPUS:84928479265
SN - 0301-7516
VL - 139
SP - 1
EP - 10
JO - International Journal of Mineral Processing
JF - International Journal of Mineral Processing
ER -