Adsorption Equilibrium for Heavy Metal Divalent Ions (Cu²⁺, Zn²⁺, and Cd²⁺) into Zirconium-Based Ferromagnetic Sorbent

Figure 3

FT-IR spectra of the zirconium-based ferromagnetic sorbent (a) before and after sorption of (b) Cu²⁺, (c) Zn²⁺, and (d) Cd²⁺ [experimental conditions: sorbent dosage = 1 g/L, initial concentration = 200 mg/L, and contact time = 24 h].