Valorization of Ginger Waste-Derived Biochar for Simultaneous Multiclass Antibiotics Remediation in Aqueous Medium

The presence of antibiotics in the aqueous environment has been a serious concern primarily due to the development of antimicrobial resistance (AMR) in diverse microbial populations. To overcome the rising AMR concerns, antibiotic decontamination of the environmental matrices may play a vital role. The present study investigates the use of zinc-activated ginger-waste derived biochar for the removal of six antibiotics belonging to three different classes, viz., β-lactams, fluoroquinolones, and tetracyclines from the water matrix. The adsorption capacities of activated ginger biochar (AGB) for the concurrent removal of the tested antibiotics were investigated at different contact times, temperatures, pH values, and initial concentrations of the adsorbate and adsorbent doses. AGB demonstrated high adsorption capacities of 5.00, 17.42, 9.66, 9.24, 7.15, and 5.40 mg/g for amoxicillin, oxacillin, ciprofloxacin, enrofloxacin, chlortetracycline, and doxycycline, respectively. Further, among the employed isotherm models, the Langmuir model fitted well for all the antibiotics except oxacillin. The kinetic data of the adsorption experiments followed the pseudo-second order kinetics suggesting chemisorption as the preferred adsorption mechanism. Adsorption studies at different temperatures were conducted to obtain the thermodynamic characteristics suggesting a spontaneous exothermic adsorption phenomenon. AGB being a waste-derived cost-effective material shows promising antibiotic decontamination from the water environment.