Alkali Activated Slag as Adsorbents for Cu2+ Removal from Wastewaters

Abstract

The removal of heavy metals from wastewaters is presently a global imperative primarily due to their well-known toxic nature and detrimental effects on the environment, and more importantly, on human health. Currently, special attention is paid to the use of novel slag based materials – alkali activated slag (AAS) as potential novel adsorbents. Our previous studies have shown that electric arc furnace slag (EAFS) can be successfully used as a precursor for the production of AAS. Generally, alkaline activation involves a chemical reaction between solid aluminosilicate materials and a highly alkaline activator. The alkali activation mechanism of slag involves the dissolution of slag in a highly alkaline, which is followed by the condensation and hardening processes. Dependent on the pH and type of alkaline activator, calcium (alumina) silicate hydrate or C–(A)–S–H gel has been identified as a reaction product of slag alkali activation. The objective of this research was to investigate the removal of Cu2+ from aquatic solution using alkali activated slag (AAS) obtained by alkaline activation of EAFS.