Efficient removal of ciprofloxacin using agro-waste biochar derived from soya stalks (Glycine max): Investigations on adsorption characteristics under varying environmental conditions

Mismanagement of antibiotics is a global problem affecting environmental and human health. In the present study, soya stalks (SS) derived biochars were prepared using thermochemical method for the effective removal of ciprofloxacin from water. The synthesized adsorbents succeeded in removing ciprofloxacin (CIP) in the range of 50-98% with a maximum removal efficiency of ∼98% using biochar synthesized at 900 ° C. Notably no chemical treatment was given for biochar synthesis. The linear and non-linear isotherm models were studied, revealing the dominance of chemisorption. The presence of -oxy functional groups, hydrogen bonding, π-π interaction, and electrostatic interaction was considered responsible for this. No considerable difference was observed upon incorporating different agitation mechanisms for SS900 biochar, further substantiating the robustness of the prepared adsorbent. Another fascinating finding was that presence of various contaminants in water, such as nitrate, alkalinity, total organic carbon, and total dissolved solids, did not influence the adsorption of CIP using the synthesized adsorbent, retaining the removal efficiency in the range of 94-98%. This study has the potential to utilize agricultural waste and reduce carbon footprint by avoiding the open burning of soya stalks. Furthermore, contribution approaches towards achieving the Sustainable Development Goals of ‘Good Health and Well-being (SDG #3) and ‘Clean Water and Sanitation (SDG #6), along with the circular economy.