Researchers have characterized the sorbents Pc, Cal-LDH, and Cal-LDH-PC to determine their adsorption capacity for heavy metals like Zn, Cd, Ni, and Pb. Their findings indicated that Cal-LDH-PC had the highest adsorption capacity, followed by Cal-LDH and then Pc. The highest removal efficiency (RE) values were obtained for Cal-LDH-PC, and the minimum for the Pc sorbent. SEM analysis revealed that Cal-LDH-PC had a porous structure with active sites for metal adsorption.
FTIR analysis showed that Cal-LDH-PC had the highest number of functional groups, suggesting strong bonds with heavy metals through electrostatic interactions. The sorbents also exhibited pi-pi interactions with the metals, aiding in their removal. BET analysis indicated that Cal-LDH-PC had a larger surface area and pore size compared to the other sorbents, enhancing its adsorption capacity.
Using response surface methodology (RSM) and Taguchi methods, researchers optimized the operational factors for maximum removal efficiency. The results showed that concentration, reaction time, sorbent dose, and pH played significant roles in the adsorption process. The RSM model accurately predicted the RE% of the metals compared to Taguchi.
The sorbents were also tested for their reusability, with Cal-LDH-PC showing good stability and regeneration ability after multiple cycles. This study highlights the importance of safe disposal of sorbents loaded with heavy metals to prevent further environmental contamination. The results provide valuable insights for designing efficient sorbents for heavy metal removal applications.
