Adsorptive removal of chloramphenicol antibiotic from aqueous solutions using functionalised biochar developed from...

Owing to their multifaceted benefits in sustainability, superior material characteristics, and environmental applications, biochar-reinforced advanced nanocomposites have become a prominent research focus. The current study addresses the contamination of water sources by antibiotics, primarily chloramphenicol (CAP), and its removal using a biochar composite. The biochar composite (GMBC_ZIF-67) was synthesised from the manure of Capra aegagrus hircus following a cost-effective approach. Characterisation results revealed that the material has mesoporous pores/structure, with an average pore diameter of 3.829 nm and a surface area of 542.22 m²/g. Batch adsorption studies demonstrated excellent CAP removal, achieving up to 99.38 % efficiency. Kinetic analysis revealed that the pseudo-second-order and Elovich models best described the adsorption process, indicating that the adsorption rate is controlled by surface interactions and the number of available reactive sites. Additionally, a decrease in adsorption was observed with increasing adsorbate concentration. Adsorption isotherm experiments indicate monolayer adsorption of CAP onto the heterogeneous active sites of GMBC_ZIF-67. Comparative studies with goat manure biochar (GMBC) and other similarly prepared materials confirmed that GMBC_ZIF-67 achieved the highest CAP removal percentage. Regeneration studies for the material were conducted till the fourth cycle. Overall, this study advances a sustainable method of wastewater treatment by converting animal waste into effective adsorbents through ZIF-67 activation and addressing the issue of antibiotic contamination and its removal from water sources.