Vermiculite-based sorbents modified with compounds of various natures

The aim of this study was to investigate the effect of organic and inorganic modifiers on the internal structure and surface properties of vermiculite from the Kovdor deposit in an alkaline medium. Vermiculite from the Kovdor deposit was treated with modifiers of various natures in an alkaline medium (sodium hydroxide, sodium stearate) with the sequential introduction of copper chloride and potassium hexacyanoferrate (II) solutions. It was shown that the introduction of stearate ion, according to X-ray phase analysis, leads to an increase in the interplanar distance compared to the original vermiculite. At the same time, an increase in the volume of the coherent scattering region indicates an increase in the degree of crystallinity and significant interaction of the modifier with the surface. Further addition of potassium ferricyanide leads to an even greater increase in the interplanar distance due to the bulk hexacyanoferrate ion, but a sharp drop in the volume of the coherent scattering region indicates the exfoliation process of the layered silicate, which leads to a decrease in the surface area due to an increase in amorphism.