Preparation of Nanoporous Sorbent Based on Bentonite Clay and Aluminum Complexes for Use in Water Purification Processes

Aluminum-intercalated materials were prepared from the native and sodium forms of bentonite clay and aluminum polyoxocomplexes using the method of intercalation and subsequent heat treatment at 500°C. The structure and physicochemical properties of the prepared materials were examined. It was found that the intercalated materials had a microporous structure characterized by a specific surface that was twice as large as that of the bentonite clay. The adsorption properties of the materials towards the anionic dye Acid Yellow 36 were studied. The sorption capacity of the intercalated materials increased by up to seven times compared to the initial clay. The physicochemical factors that affect the adsorption properties were identified. According to the IUPAC classification, the dye adsorption isotherm was categorized as type II. The kinetics of the dye adsorption are consistent with the pseudo-second-order kinetics model with a correlation coefficient of 0.9996. The process of dye adsorption onto the Al-intercalated materials is spontaneous and endothermic. The prepared sorbents can be used to remove anionic contaminants from water.