Renewable cellulose aerogel embedded with nano-HFO for preferable phosphate capture from aqueous solution

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Excess phosphate in water leads to eutrophication, necessitating effective removal strategies.
• Developing adsorbents with high phosphate adsorption capacity is crucial for water remediation.
• Existing methods require improvement in efficiency and adsorbent performance.

Purpose of the Study:

• To develop a novel nanocomposite adsorbent for efficient phosphate removal from water.
• To investigate the adsorption capacity, kinetics, and selectivity of the new material.
• To evaluate the regenerability and practical applicability of the adsorbent in wastewater treatment.

Main Methods:

• Synthesis of a nanocomposite by confining hydrated ferric oxide (HFO) nanoparticles within a cellulose aerogel (CA) network (HFO@CA).
• Batch adsorption experiments to assess phosphate uptake under varying pH and temperature conditions.
• Kinetic modeling using the pseudo-second-order model and evaluation of selectivity against competitive anions.

Main Results:

• HFO@CA demonstrated maximum adsorption capacity under near-acidic pH conditions.
• Phosphate adsorption capacity increased with rising temperature, indicating favorable adsorption thermodynamics.
• The adsorbent exhibited fast adsorption kinetics, accurately described by the pseudo-second-order model, and high selectivity for phosphate.
• Five adsorption-desorption cycles showed no significant loss in adsorption capacity, confirming excellent regenerability.

Conclusions:

• The HFO@CA nanocomposite is a highly effective and regenerable adsorbent for phosphate removal from wastewater.
• The porous structure of cellulose aerogel enhances the accessibility and utilization of HFO nanoparticles.
• This study presents a new strategy for developing high-performance adsorbents from renewable cellulose resources for environmental applications.