Material composition and beneficiation potential of vermiculite from the Tebinbulak deposit

This study investigates vermiculite, an associated mineral of the Tebinbulak iron-magnetite deposit near Nukus, Republic of Karakalpakstan. The analytical methods included mass spectrometry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and infrared spectroscopy (IR). In addition to vermiculite, the ore was shown to contain biotite, annite, and phlogopite. Chemical analysis identified the dominant oxides as SiO2 (40.3 wt.%), MgO (21.5 wt.%), Fe2O3 (11.3 wt.%), and Al2O3 (9.9 wt.%), with minor amounts of K2O (3.6 wt.%) and Na2O (0.9 wt.%). Structural analysis confirmed the presence of tetrahedral, octahedral, and interlayer phases typical of vermiculite. To assess beneficiation potential, the solubility of vermiculite in various aqueous acids and oxidizers was studied with the goal of isolating magnesium compounds for defoliant production. Solvents included HCl, H2SO4, NaClO, H2O2, and distilled water. Ore samples were crushed to < 45 μm using ShchD-6 jaw and IVS-4 vibratory crushers and classified with a Retsch AS 450 control sieve. Solubility, pH, and density were determined for the processed samples. The most efficient dissolution was observed at 25 °C using HCl, H2O2, and NaClO, particularly for the material below 45 µm. Acid leaching proved to be an effective method for producing magnesium-bearing solutions.