Sorption of Pb2+ on mercapto functionalized sepiolite

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Lead (Pb(2+)) contamination in aqueous solutions poses significant environmental and health risks.
• Developing efficient and cost-effective adsorbents for heavy metal removal is crucial.

Purpose of the Study:

• To prepare mercapto functionalized sepiolite (MSEP) via nanotexturization.
• To investigate the sorption performance and mechanisms of MSEP for Pb(2+) removal from aqueous solutions.

Main Methods:

• Nanotexturization for MSEP preparation.
• Characterization using XRD, FT-IR, NMR (29Si, 13C CP/MAS), and XPS.
• Sorption studies including thermodynamic, kinetic, and effect factor analyses.

Main Results:

• MSEP exhibited a maximum sorption capacity of 97 mg g(-1) for Pb(2+).
• The sorption process was endothermic and spontaneous (ΔH(0) = 33.637 kJ mol(-1), ΔS(0) = 202.697 J mol(-1) K(-1)).
• Freundlich isotherm and pseudo-second-order kinetic models best described the sorption data.

Conclusions:

• MSEP is an effective adsorbent for Pb(2+) removal.
• Sorption mechanisms involve a combination of chemical and physical adsorption, influenced by pH.