Removal of tetracycline using new biocomposites from aqueous solutions

Abstract

This study investigated the removal of tetracycline (TC) using polypropylene (PP), polystyrene (PS), Saccharomyces cerevisiae (Sc) yeast, and new types of sorbents such as polypropylene–S. cerevisiae (PP–Sc) and Polystyrene–S. cerevisiae (PS–Sc) biocomposites from aqueous solutions in a batch system. PP–Sc and PS–Sc are newly synthesized yeast immobilized polymers for the removal of TC. The experimental results showed that the maximum TC removal was obtained by using the PP–Sc biocomposite, which has a porous structure necessary for the adsorption process and live yeast is a good biosorbent that is necessary for the biosorption process. The experimental conditions were investigated as a function of pH (4–12), the TC amount (10–150 mg/L), the adsorbents amount (0.05–0.6 g/L), the temperature (25–55°C), and the NaNO₃ amount (0.025–1 mg/L). The Freundlich and Langmuir adsorption isotherms were conducted to deduce the mechanism of the removal process and both of the results were compatible. The thermodynamic parameters for the removal process and the structure characteristics of PP–Sc, both before and after the TC removal, were determined. This study proved that the PP–Sc and PS–Sc biocomposites have different features than the original and can cause significant implications for environmental biotechnologies, in particular for the removal of TC.

Keywords:

• Tetracycline removal
• Polypropylene–Saccharomyces cerevisiae biocomposite
• Polystyrene–Saccharomyces cerevisiae biocomposite