Optimization of removal of sulfonamide antibiotics by magnetic nanocomposite from water samples using central composite design

Abstract

The present study aimed to remove sulfonamide antibiotics from water samples using magnetic Fe3O4-bentonite nanocomposite (Fe3O4-Bt) as an adsorbent. The adsorbent has a surface area of 74.27 m2 g-1, a pore size of 87.53 nm, and a pore volume of 0.146 cm3 g-1. A central composite design (CCD) matrix was employed to model and optimize the process. The optimal conditions for removing sulfonamide antibiotics were determined using Fe3O4-Bt adsorbent at an antibiotic concentration of 20 mg L-1, the amount of nanoparticles of 0.23 g, pH of 6, and ultrasonication time of 17 min. The reusability study of the Fe3O4-Bt adsorbent showed that the Fe3O4-Bt could be used five times in adsorption/desorption processes. Also, applying the Fe3O4-Bt adsorbent on real samples revealed that Fe3O4-Bt adsorbent could remove sulfonamide antibiotics in the range of 86.85–97.47% with RSD (n = 5) < 4.

Keywords

• Sulfonamide antibiotics
• Magnetic nanocomposite removal
• Response surface methodology