Fe/S modified sludge-based biochar for tetracycline removal from water

In this study, a novel sludge-based material was synthesized by activation and modification, and was applied in tetracycline (TC) removal from water. For detecting the concrete structure of this adsorbent, SEM，TEM, FTIR, XRD, BET and XPS were employed. And removal mechanisms of TC by the composite were analyzed by fitting experimental data with various mathematics models. Besides, the effect of foreign ions on adsorption, the removal performance of TC from natural water and recyclability of the synthetic material were also investigated. Batch experiments results showed the composite was an efficient adsorbent for TC removal from water with adsorption capacity of 174.06 mg/g at 298 K. And adsorption mechanisms could be attributed to pore filling, π-π stacking, hydrogen bonding interaction, ion exchange, complexation, electrostatic attraction etc. The superior capability of this adsorbent demonstrated it as a potential material for TC removal from water, and provided a guideline to design promising adsorbents for contaminant removal.