Grain-size and Phase Transformations of Quartz-containing Products during Vibration Grinding for Analytical Sample Preparation

   High-quality sample preparation is a critical step in the X-ray diffraction (XRD) analysis, but traditional methods for grinding quartz-containing materials are labor-intensive and time-consuming (up to 90 min). A rapid sample preparation ensures intensive mechanical action that does not distort the phase composition of the material.

   Purpose: Investigation of granulometric and phase transformations of quartz-containing products during vibrational grinding for the analytical sample preparation.

   Methodology: River sand samples in different fractions (1.25–0.63, 0.63–0.315, 0.315–0.16 and < 0.16 mm) were mechanically activated in an IV-Micro vibratory grinder for 5 and 10 min. The particle size distribution was measured by sieving using 0.9–0.071 mm sieves. A Shimadzu XRD-6000 diffractometer was used to study phase transformations. The samples crushed manually in an agate mortar and in a vibratory grinder were compared.

   Research findings: It was found that 5-min grinding reduced the content of coarse fractions (0.63 and 0.315 mm) while simultaneously increasing the proportion of fine particles (< 0.14 mm). The time increase up to 10 min led to a complete disappearance of > 0.315 mm particles and the accumulation of the ultrafine phase. The XRD analysis showed that vibratory grinding did not affect the phase composition of quartz, i. e., only the SiO₂ phase was identified in river sand and quartzite. It was found that the decrease in the relative intensity of secondary diffraction maxima was determined by the particle aggregation.

1. Avvakumov, E.G., Avvakumov, E.G., Gusev, A.A. Mechanical Methods of Activation in Processing of Natural and Technogenic Raw Materials. N.Z. Lyakhov, Ed. Novosibirsk: Geo, 2009. 153 p. ISBN 978-5-9747-0161-0. (In Russian)

2. Ibragimov, R.A., Pimenov, S.I., Izotov, V.S. Effect of Mechanochemical Activation of Binder on Properties of Finegrained Concrete. Magazine of Civil Engineering. 2015; 54(2): 63–69. DOI: 10.5862/MCE.54.7

3. Shadrinov, N.V., Kapitonov, E.A. Study of the Influence of Mechanical Activation of Carbon Black on the Properties of Butadiene–Nitrile Rubber. Arktika XXI vek. Tekhnicheskie nauki. 2014; 1(2): 20–29. (In Russian)

4. Chudaeva, A.A. Influence of Mechanical Activation on Properties of Cement–Ash Composites. MS Thesis. Krasnoyarsk: Siberian Federal University. 2018. (In Russian)

5. Endzhievskaya, I.G., Vasilovskaya, N.G., Dubrovskaya, O.G., Baranova, G.P., Chudaeva, A.A. Influence of Mechanical Activation on Property Stabilization of Fly Ash from Krasnoyarsk CHP Plants. Zhurnal Sibirskogo federal'nogo universiteta. Seriya: Tekhnika i tekhnologii. 2018; 11(7): 842–855. (In Russian)

6. Trushin, V.N., Andreev, P.V., Faddeev, M.A. X-ray Phase Analysis of Polycrystalline Materials : Electronic Educational and Methodological Guide. Nizhny Novgorod: Nizhny Novgorod State University, 2012. 89 p. (In Russian)

7. Kovba, L.M., Trunov, V.K. X-ray Phase Analysis. Moscow: Moscow State University, 2^nd edn. 1976. Pp. 15–40. (In Russian)

8. Dubkova, N.Z., Ivanova, G.I., Galiakberov, Z.K., Nikolaev, N.A. Grinding Kinetics in a Vibratory Dryer–Mill in the Production of Powders from Plant Raw Materials. Izvestiya vuzov. Pishchevaya tekhnologiya. 2002; (5-6): 35–38. (In Russian)