Sheet-like graphitized glucose-based mesoporous carbon for aqueous adsorption of tetracycline antibiotic

Abstract

Antibiotics are an emerging water pollutant without universally agreed regulations. Hence, its removal from the water will minimize antibiotics resistance bacteria. Herein, facile pyrolysis at 500 °C for 3 h was deployed to convert d-glucose to sheet-like graphitized carbon (GLU-500) for the removal of tetracycline antibiotics. The carbon material was characterized and the effect of pH, contact time, and initial concentration of tetracycline was elucidated. Results revealed that pyrolysis temperature tailored the morphology, functional group, and textural characteristics to accumulate a high amount of tetracycline. Electrostatic attraction at a pH of 5 favored the highest removal of 138.32 mg g−1of tetracycline at 30 °C, however, this adsorption capacity declined at increasing pH due to the formation of zwitterions that imposes a diffusion barrier. A multilayer adsorption was observed for the tetracycline-GLU-500 system, which was best described by Freundlich isotherm with R2 of 0.94−0.99. Also, the pseudo-second-order kinetic model confirms that thetetracycline-GLU-500 system adsorption is mainly by chemical interaction. The study confirms that abundant glucose can be a sustainable precursor for treatment of antibiotics contaminated water.