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    Effect of Blunging/Dispersion Parameters on Separation of Halloysite Nanotubes from Gangue Minerals
    (Mdpi, 2022) Durgut, Emrah; Cinar, Mustafa; Terzi, Mert; Unver, Ilgin Kursun; Yildirim, Yildiz; Boylu, Feridun; Ozdemir, Orhan
    Clay minerals need to be dispersed with blungers before their utilization in the related industries due to their plastic properties, and size reduction is carried out in a wet medium. Clay minerals also contain impurities such as nonplastic materials in their structure. Mechanical dispersion parameters are important in the separation of clay group minerals (halloysite and kaolinite) from their typical non-clayey gangue minerals (quartz and goethite). In this study, the removal of impurities from halloysite ore obtained from Kizildam, Turkey, was examined in terms of mechanical dispersion parameters, namely, feed size, blunging time and speed, pulp concentration, pulp temperature, and the aging process. The effect of these parameters on halloysite dispersion was determined by particle size, chemical, and mineralogical analysis, and optical and scanning electron microscope images. The results obtained from the studies of the mechanical dispersing and particle size distribution of the products indicated that the optimum dispersion parameters were determined as -10 mm feed size, 8 h, and 1000 rpm blunging time, and speed, 35% pulp concentration at 25 degrees C pulp temperature. Under these optimum conditions, a 72.3% amount of -38 mu m clay product containing 35.6% of halloysite, 46.5% of kaolinite, 12.0% quartz, 1.9% goethite, 0.9% gibbsite, and 3.2% other minerals were obtained from the halloysite ore, having 30.5% of halloysite, 43.4% of kaolinite, 19.1% quartz, 2.9% goethite, 1.4% gibbsite, and 2.7% other minerals. In this study, it was understood that feed size, pulp concentration, blunging time, and speed were important parameters, while pulp temperature and the aging process had no significant effect on the mechanical dispersion of Kizildam halloysite. In addition, impurities such as quartz and iron-bearing minerals were separated from the ore by blunging and sieving.
  • [ X ]
    Öğe
    Evaluation of Different Dispersants on the Dispersion/Sedimentation Behavior of Halloysite, Kaolinite, and Quartz Suspensions in the Enrichment of Halloysite Ore by Mechanical Dispersion
    (Mdpi, 2022) Durgut, Emrah; Cinar, Mustafa; Terzi, Mert; Unver, Ilgin Kursun; Yildirim, Yildiz; Ozdemir, Orhan
    In this study, the dispersion properties of pure halloysite, kaolinite, and quartz minerals in halloysite ore were determined in the absence and presence of dispersants (sodium silicate, STPP, SHMP). First of all, the samples were characterized by chemical, mineralogical, BET, FTIR, and TEM analyses. Afterward, the physico-chemical properties of these minerals were investigated by zeta potential measurements and dispersion/sedimentation experiments in the absence and presence of the dispersants. The zeta potential measurements showed that the surface charges of all minerals changed from negative to positive as the PH changed from basic to acidic. The presence of dispersants at natural pHs indicated that the mineral surface charges tended to become more negative as the concentration increased in the zeta potential measurements. SHMP showed the most effect on the zeta potential. In the dispersion/sedimentation experiments, settling was slowed down with the use of dispersants. Finally, the dispersion properties of halloysite ore in the presence of dispersants were explored using mechanical dispersion and pulp viscosity experiments based on the amount of material passing to <38 mu m size and the chemical changes in the materials. As a result of the mechanical dispersion tests carried out in the presence of dispersants (sodium silicate, STPP, SHMP), 71.3% of the material with 30.8% Al2O3 and 50.5% SiO2 content passed to <38 mu m size without using dispersant, and 73.2% of <38 mu m sized material with 35.5% Al2O3 and 46.1% SiO2 content was gained in the use of 7.5 kg/ton SHMP, which was determined as the optimum within the scope of the study. In conclusion, dispersant use enhanced the mechanical dispersion effect for plastic clay mineral separation from hard minerals in an aqueous medium.