Elucidating facile biosorptive eradication of enrofloxacin: Equilibrium, kinetics, reusability, cost estimation, and safe disposal

Abstract

AbstractIn the current investigation, superheated steam activated green coconut shell (Cocos nucifera) biochar (PAGCSB) has been used in sorptive expulsion of the pharmaceutical micro‐pollutant enrofloxacin (ENX) from water. Through a number of progressive studies in batch sorption process, the influence of some crucial parameters are evaluated toward efficacious remediation of ENX laden aqueous media by PAGCSB. The parameters studied are: contact time (5–20 h); mixing intensity (100–190 rpm); pH (1–9); initial ENX concentration (5–35 mg/L); temperature (15–40°C); and biosorbent dosage (2–5 g/L). The maximum ENX removal is 91.92% by using ENX initial concentration 20 mg/L; pH 7; temperature 30°C; biosorbent dose 4 g/L; stirring speed 150 rpm; and contact period 16 h. The repeated usability of spent biochar has been assessed and found to be 69.91% even after the fifth cycle. The pseudo‐second order kinetic model provided the best fit to the kinetic data. The Langmuir model showed the finest suit to the isotherm data. Adsorption capacity of the biosorbent was observed to be 2.32 mg/g. The current study on biosorptive riddance of ENX revealed a good level of randomness in the thermodynamic process which is found to be exothermic in nature. A wide‐scale utilization of the developed biosorbent has been well‐substantiated by the cost estimation. Finally, the safe disposal of spent biosorbent has been studied in accordance with the World Health Organization safety guidelines. Hence, superheated steam activated green coconut shell derived biochar could be a cost‐effective and competent sorbent material for ENX eradication from contaminated water.