Efficient phosphate removal utilizing N, Zn-doped carbon dots as an innovative nanoadsorbent

Area of Science:

• Environmental Science
• Materials Science
• Chemistry

Background:

• Phosphate (PO43-) pollution in aqueous solutions poses significant environmental challenges.
• Developing cost-effective and efficient adsorbents is crucial for water remediation.

Purpose of the Study:

• To investigate the adsorption of phosphate (PO43-) from aqueous solutions using novel zinc-doped carbon dots (Zn-N-CDs).
• To explore the potential of Zn-N-CDs as a sustainable adsorbent for environmental remediation.

Main Methods:

• Zn-N-CDs were synthesized via a hydrothermal process.
• Adsorption experiments were conducted to evaluate the effects of reaction time, temperature, pH, ionic strength, adsorbent dosage, initial concentration, and competing anions.
• Characterization of Zn-N-CDs was performed using various analytical techniques.

Main Results:

• Zn-N-CDs exhibited a spherical structure with porous morphology and high affinity for PO43- adsorption, reaching equilibrium within 5 minutes.
• Optimal adsorption occurred at pH 8, with 100 mM KCl ionic strength, and 5 g L-1 adsorbent dosage.
• Adsorption followed pseudo-second-order kinetics and Freundlich isotherm models, indicating multi-layer chemisorption.

Conclusions:

• Zn-N-CDs demonstrate excellent performance in adsorbing high concentrations of phosphate across a broad pH range.
• The findings highlight the potential of Zn-N-CDs as an effective and economical adsorbent for phosphate removal in environmental applications.