ADVANCES IN QUANTITATIVE RIETVELD ANALYSIS (XRPD) FOR MINERALS AND MINING APPLICATIONS

X-ray powder diffraction (XRPD) combined with quantitative Rietveld analysis is an essential tool for the determination of relative phase amounts in crystalline materials, including both powdered solids and slurries; analysis times are normally less than 10 minutes per sample. In the minerals and mining industries, quantitative phase analysis by XRPD allows characterization and optimization of the process from exploration, processing, through to waste stockpiling. Currently, XRPD finds exponentially growing interest in important application areas such as in leaching and flotation processes (optimization of acid consumption, pH control, etc.) and in environmental mineralogy (prediction and control of acid rock drainage, verification and quantification of carbon dioxide sequestration, etc.). The talk will illustrate the use and approach of a fundamental parameter (FP) based Rietveld analysis using different mineralogical matrices:

In the past quantification of minerals with not well known and defined crystal structures was impossible. Scarlett (2006) describes a new approach for the quantification of phases with partial or no known crystal structure referred to as PONKCS. This approach translated into the TOPAS® is applied to clays and clay containing mineral assemblies encountered during an exploration project.

Literature:

Details of this methodology have been published in:

Scarlett, N.V.Y. and Madsen, I.C., (2006), Quantification of phases with partial

or no known crystal structures, Powder Diffraction, Vol 21, 4, 278-284.

Details of general QPA including this methodology are in press in:

Madsen, I.C and Scarlett, N.V.Y. (2007), Quantitative Phase Analysis,

Chapter 9 in Powder Diffraction: Theory and Practice, Royal Society of

Chemistry.