Adsorption and Reusability Performances of Ni/Al Layered Double Hydroxide for the Removal of Eriochrome Black T Dye

This work deals with the synthesis, characterization, and adsorptive removal performances for eriochrome black T (EBT) dye of Ni/Al lamellar double hydroxides (Ni-Al-LDH). The characterization results showed that the material exhibited excellent crystallinity and an excess of hydroxyl groups on its surface with better textural properties. Also, after interaction with EBT, FT-IR spectroscopy showed that EBT was on both surfaces adsorbed and intercalated by the material. Adsorption experiments results showed higher adsorption in an acidic pH medium. The adsorption process followed the pseudo-first-order kinetic model, and the Langmuir equation adequately described the equilibrium data. The maximum adsorption capacity was 37.71 mg/g at an initial dye concentration of 20 mg/L, contact time of 120 min, and temperature of 298 K. The thermodynamic parameters indicate spontaneous and exothermic physisorption process. Finally, the adsorption performance after three successive regeneration cycles shows that Ni-Al-LDH has superior adsorption and reuse performance for EBT dye, indicating that the material could be used as an effective adsorbent for the decontamination of anionic dyes in wastewaters.