Two-step fabrication of cellulose embedded Fe

Area of Science:

• Environmental Chemistry
• Materials Science
• Catalysis

Background:

• Sulfamethoxazole (SMX) is a common pharmaceutical pollutant in water.
• Developing efficient and reusable catalysts for pollutant degradation is crucial for environmental remediation.
• Magnetic nanoparticles offer advantages in catalyst separation and recovery.

Purpose of the Study:

• To synthesize and characterize magnetic beads for Fenton-like degradation of SMX.
• To investigate the efficiency and influencing factors of SMX degradation.
• To evaluate the performance of the magnetic beads in real sewage water treatment.

Main Methods:

• Magnetite nanoparticles were embedded in sodium carboxymethyl cellulose (Na-CMC) using FeCl3 cross-linking.
• Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) were used for characterization.
• Batch experiments were conducted to study SMX degradation efficiency under varying pH, catalyst dosage, and initial SMX concentration.

Main Results:

• The synthesized beads were confirmed to contain magnetite nanoparticles within the Na-CMC matrix.
• Optimal conditions (pH 4.0, 0.2 g L⁻¹, 30 mg L⁻¹ SMX) resulted in 81.89% SMX degradation and 81.2% COD reduction in 40 min.
• The catalyst demonstrated effectiveness in a floating bed column for sewage water treatment, achieving 79% COD reduction, and was reusable for 2-3 cycles.

Conclusions:

• Na-CMC magnetic beads function as effective Fenton-like catalysts for SMX degradation.
• The catalyst's stable structure, textural properties, and active sites contribute to its efficiency.
• Further optimization is needed for complete SMX mineralization, potentially by increasing iron content for enhanced hydroxyl radical generation.