Unmodified Mg/Al layered double hydroxide clay with versatile and specific adsorption capacity over high spectrum type of harmful contaminants

Abstract

The present study investigates the effectiveness of Mg/Al layered double hydroxide (MATclay) for adsorbing Congo Red dye (CR) from wastewater. MATclay was prepared using a cost-effective co-precipitation method at pH 9.5, ensuring both chemical and mechanical stability. The in-depth physico-chemical characterization of MATclay sample was performed using various techniques, including FE-SEM, FT-IR, XRD, DLS, BET surface area, Zeta potential, TEM, XPS, XAS, and TGA. Batch experiments were performed to evaluate the adsorptive performance under different conditions (30–100 mg/L initial concentration, 298–320 K temperature range, and 5–180 min contact time). The adsorption data fit best with the Langmuir model, indicating monolayer adsorption with a maximum capacity of 60.61 mg/g. Post-adsorption analysis with SEM, XRD, and TGA confirmed the interaction of CR with MATclay. Furthermore, the MATclay material was applied as potential adsorbent for other type of pollutants, namely cationic dye (Methylene Blue) and antibiotics (Metronidazole, Tetracycline, and Cefotaxime), the data obtained in this complementary study showing good results for the removal of Tetracycline and Cefotaxime antibiotics. Overall, MATclay demonstrates potential as an effective adsorbent for CR dye and other pollutants in wastewater treatment.