Research of the activity of Fe-pillared montmorillonites in aqueous dye solution

Abstract

High specific surface area, large micropore volume, concentration of surface acid sites, and increased density of sorption sites make montmorillonite pillared as an excellent adsorbent and catalyst to remove contaminants from wastewater. The studies are aimed at establishing the adsorption and catalytic activity of Fe pillared montmorillonite based on Krantau and Navbakhor bentonite in relation to dyes from solutions. It has been shown that the introduction of Fe3+ ions into the interlayer space of a natural sample increases the activity with respect to the anionic dye by more than 2 folds. Despite the large specific surface area of the original Navbakhor clay, compared to Krantau clay, the activity for Congo red is greater in the pillar of the latter. It has been established that Fe-pillared materials are active catalysts for the oxidation of dyes by hydrogen peroxide in aqueous solutions and lead to its 100% conversion. An increase in the temperature of catalytic oxidation ranged from 25 to 55°C increases the discoloration degree of Congo red solution under homogeneous conditions by 1.5 folds or more, and under conditions of heterogeneous catalysis at least three folds.