Modification of Bamboo Biochar With Chitosan for Efficient Removal of Ciprofloxacin From Aqueous Media

This study evaluates a novel adsorbent for ciprofloxacin (CPX) removal from water using chitosan‐modified bamboo biochar (CMBB). To evaluate biochar's adsorption tendency for removing CPX from water, batch adsorption experiments were conducted. Under the 10 mg L −1 initial CPX concentration and a biochar dosage of 1 g L −1 , pH (2.00–10.00), incubation time (2–1440 min), adsorption experiments were conducted. By changing the initial CPX dosage (2–25 mg L −1 ), isotherm experiments were conducted. Biochar was characterized using proximate analysis and FTIR analysis. Maximum CPX adsorption was observed at 120 min contact time and pH 7.60. Kinetics data were best fitted with the Elovich model ( R 2 = 0.987), suggesting the presence of energetically heterogeneous adsorption sites on the biochar surface. Isotherm data best interpreted by the Hill isotherm model ( R 2 = 0.988), indicating cooperative binding of CPX on a heterogeneous biochar surface. For the CMBB, a maximum adsorption capacity of 10.918 ± 0.671 mg g −1 was recorded, while 7.063 ± 0.552 mg g −1 was for pristine biochar. It can be elucidated that the CPX adsorption mechanism is primarily driven by hydrogen bonding, alongside the contribution of pore‐filling and electrostatic interactions. These results demonstrate the potential of CMBB for effective CPX removal from aqueous medium.