Alkali-activated metallurgical slag as a sustainable adsorbent

Abstract

This paper is devoted to obtaining a zeolite-containing sorbent based on metallurgical waste — slag. The synthesis of zeolite adsorbent from ash and slag was carried out by hydrochemical and thermal treatment. The initial object and the obtained material were characterized using following methods: Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive analysis, X-ray phase analysis, titrimetry. The way of converting solid-phase waste into a beneficial product has been demonstrated. The study results showed that the surface of the obtained material is saturated with functional groups (hydroxy-, carboxy-, lactone), which predetermine the ability to bind metal ions during adsorption. The adsorption capacity of the product has been estimated for iodine and methylene blue. A thermodynamic analysis of the process of sorption of copper (II) ions from an aqueous solution has been conducted. It has identified that the sorbent can also be used for the adsorptive concentration of ions of rare-earth elements by the example of lanthanum and erbium. Laboratory testing of the possible use of the sorbent to purify industrial water was carried out using the example of wastewater from a chromium plating shop.