Application of goethite modified biochar for tylosin removal from aqueous solution

Recent investigations have shown frequent detection of pharmaceuticals in soils and waters posing potential risks to human and ecological health. Here, we report the enhanced removal of tylosin (TYL) from water by a novel goethite biochar (BCF) composite. Characterization by scanning electron microscopy (SEM) images showed good dispersion of goethite nanoparticles on the biochar surface. The coating was constructed by well-crystallized cubic phase goethite nanoparticles as examined by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. To evaluate the feasibility of BCF composite as a potential adsorbent for antibiotic removal, batch sorption experiments were conducted using TYL as the model antibiotic molecule. The results showed that this adsorbent showed rapid and high sorption of TYL. According to the Henry and Freundlich model, the maximum capacities of TYL on BCF were 8132.89 L/kg and 5386.76 (mu g/g)/(mg/L)(n) respectively. Besides, the sorption capacity of TYL on BCF was obviously affected by pH and ionic strength. The sorption mechanisms of TYL on BCF were contributed to hydrophobic, electrostatic, H-bonding, cation exchange and pi-pi EDA interaction. The present work suggests that BCF composite, owing to their simple preparation procedures, high sorption capacity, low cost, and environmentally benign nature, have great potential as the next-generation adsorbent in the removal of antibiotics and other emerging contaminants. (C) 2016 Elsevier B.V. All rights reserved.