Efficient Schiff base ligand for selective Cd(ii) and Pb(ii) removal from water

Area of Science:

• Materials Science
• Environmental Chemistry
• Analytical Chemistry

Background:

• Heavy metal contamination in aqueous solutions poses significant environmental and health risks.
• Efficient and selective removal of toxic heavy metals like lead(II) and cadmium(II) is crucial for water treatment.

Purpose of the Study:

• To develop and evaluate a novel Schiff base ligand for the efficient removal of lead(II) and cadmium(II) from aqueous solutions.
• To investigate the adsorption performance and mechanism of the synthesized ligand for heavy metal remediation.

Main Methods:

• Synthesis and characterization of a Schiff base ligand (2-((E)-(4-aminophenylimino)methyl)benzoic acid).
• Batch adsorption experiments to study the effects of pH, temperature, metal ion concentration, and contact time.
• Adsorption isotherm and kinetic modeling, thermodynamic analysis, and reusability tests.

Main Results:

• The ligand demonstrated high sorption capacities: 84.0 mg g⁻¹ for Pb(II) and 71.0 mg g⁻¹ for Cd(II) at pH 6.0.
• Adsorption followed pseudo-second-order kinetics and best fitted Langmuir and Sips isotherms, indicating chemisorption.
• The process was spontaneous and exothermic, with excellent reusability and selectivity in real wastewater.

Conclusions:

• The synthesized Schiff base ligand is a highly effective, selective, and reusable adsorbent for Pb(II) and Cd(II) removal.
• This novel ligand presents a promising and sustainable solution for heavy metal remediation in water treatment applications.