Details of the quantitative techniques successfully applied to artificial rock mixtures distributed for the third Clay Minerals Society Reynolds Cup (RC) contest are presented. Participants each received three samples, two containing 17 minerals each and a third containing ten minerals. The true composition of the samples was unknown to all participants during the contest period. The results submitted were ranked by summing the deviations from the actual compositions (bias). The top three finishers used mainly X-ray diffraction (XRD) for identification and quantification. The winner obtained an average bias of 11.3% per sample by using an internal standard and modified single-line reference intensity ratio (RIR) method based on pure mineral standards. Full-pattern fitting by genetic algorithm was used to measure the integrated intensity of the diagnostic single-line reflections chosen for quantification. Elemental-composition optimization was used separately to constrain phase concentrations that were uncertain because the reference mineral standards were lacking or not ideal. Cation exchange capacity, oriented-sample XRD analysis, and thermogravimetric analysis were also used as supplementary techniques. The second-place finisher obtained an average bias of 13.9%, also by using an RIR method, but without an added internal standard and with intensity measured by whole-pattern fitting. The third-place finisher, who obtained an average bias of 15.3%, used the Rietveld method for quantification and identification of minor phases (using difference plots). This participant also used scanning electron microscopy (with X-ray microanalysis) to identify minor components and verify the composition of structures used in Rietveld analysis. As in the previous contests, successful quantification appears to be more dependent on analyst experience than on the analytical technique or software used.

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This study investigates the affinity of clay minerals in oil sands for the water-continuous tailings and hydrocarbon-continuous froth streams produced from the extraction of bitumen from oil sands. Clay minerals in oil sands processing impact bitumen flotation in separation vessels, emulsion formation during froth treatment, and fine tailings behaviour.X-ray diffraction of oriented clay slides and random powder samples were used to quantify the clay minerals in the oil sands ore and process streams. Particle size distribution and clay activity balances were also conducted around the extraction process.The degree of partitioning during the conditioning and flotation stages in a batch extractor was determined by the surface properties of the clay minerals present. The water-continuous tailings stream was further separated into fine and coarse tailings fractions through sedimentation. The bulk of the clay minerals reported to the fine tailings stream. Illite and mixed layered illite-smectite partitioned less to the hydrocarbon-continuous froth than kaolinite. Also, the illite-smectite in the froth stream appeared to be different from the illite-smectite in the water continuous streams.On aétudié dans ce travail l'affinité des minéraux argileux dans les sables bitumineux pour les courants de résidus continus dans l'eau et les courants d'écume continus dans les hydrocarbures produits par l'extraction de bitume des sables bitumineux. Les minéraux argileux dans le traitement des sables bitumineux ont un impact sur la flottation du bitume dans les cuves de séparation, la formation desémulsions lors du traitement de l'écume et le comportement des résidus. La diffraction X de préparation microscopique d'argile orientée et deséchantillons de poudres aléatoires ontété utilisés pour quantifier les minéraux argileux dans le minerai de sables bitumineux et les courants de procédés. La distribution de taille des particules et les bilans d'activité de l'argile ontégalementété déterminés autour du procédé d'extraction. Le degré de séparation durant leś etapes de conditionnement et de flottation dans un extracteur discontinu aété déterminé par les propriétés de surface des minéraux argileux présents. Le courant de résidus continus dans l'eau a ensuiteété séparé en fractions de résidus fins et grossiers par sédimentation. La grande partie des minéraux argileux se retrouve dans le courant de résidus fins. L'illite et l'illitesmectite en couches mélangées se séparent moins de l'écume continue dans les hydrocarbures que la kaolinite. Par ailleurs, l'illitesmectite dans le courant d'écume sembleêtre différente de l'illitesmectite dans les courants d'eau continus.

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