Synthetic Zeolite from Blast Furnace Slag (BFS) as an effective sorbent for simultaneous removal of Cadmium and Copper ions

The main challenge for remediation of metals contaminated water is the application of a proper, effective, low-cost material for decontamination of hazardous metal. In this study, low-cost zeolite derived from blast furnace slag (Z-BFS) by a facile hydrothermal method was investigated for adsorption of copper (Cu2+) and cadmium (Cd2+) ions from aqueous solutions. Furthermore, the characteristics of the prepared Z-BFS were evaluated via different techniques (FT-IR, XRF, XRD, SEM and EDX). The results showed the complete removal of Cd2+ and Cu2+ ions. Notably, the maximum adsorption capacity of metals had the trend Cu2+ (103 mg/g) > Cd2+ (80 mg/g) within 20 min at pH 5.5 and 2 g Z-BFS/l. The experimental data fit well with the pseudo-second order kinetic model elucidating that chemisorption is the rate determining step. The isotherms of adsorption were satisfactorily described by the Langmuir isotherm model indicating the monolayer adsorption process. The thermodynamic study demonstrated that adsorption process is endothermic. The obtained results from this study show that Z-BFS proves to be a proper candidate adsorbent for the removal of Cd2+ and Cu2+ ions from contaminated water.