Pectin/Activated Carbon-Based Porous Microsphere for Pb²⁺ Adsorption: Characterization and Adsorption Behaviour

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Heavy metal contamination poses significant environmental and health risks.
• Developing efficient and cost-effective adsorbents is crucial for water remediation.
• Pectin and activated carbon are promising materials for adsorbent development.

Purpose of the Study:

• To synthesize and characterize pectin/activated carbon microspheres (P/ACs) for lead ion (Pb²⁺) adsorption.
• To investigate the adsorption kinetics, isotherms, and mechanism of Pb²⁺ onto P/ACs.
• To evaluate the reusability and stability of P/ACs for practical applications.

Main Methods:

• Pectin/activated carbon microspheres (P/ACs) were prepared using simple gelation without chemical crosslinking.
• Adsorption experiments were conducted to study kinetics and isotherms.
• Scanning electron microscopy (SEM), texture profile analysis, and X-ray photoelectron spectroscopy (XPS) were used for characterization.
• Adsorption/desorption cycles were performed to assess reusability.

Main Results:

• SEM confirmed increased porosity with activated carbon addition.
• P/ACs exhibited good mechanical strength and high Pb²⁺ adsorption capacity (279.33 mg/g).
• Adsorption followed pseudo-second-order kinetics and Langmuir isotherm models.
• P/ACs maintained >95.5% removal efficiency over 10 cycles.

Conclusions:

• Pectin/activated carbon microspheres are effective adsorbents for Pb²⁺ removal.
• The adsorption mechanism involves ion exchange, electronic adsorption, complexation, and physical adsorption.
• P/ACs show potential as a sustainable and reusable material for treating lead-contaminated water.