Highly enhanced adsorption performance of tetracycline antibiotics on KOH-activated biochar derived from reed plants
Chuanqi Zhao, Junguan Ma, Ziyin Li, Hui Xia, Huan Liu, Yuesuo Yang
Abstract
after KOH activation. The biochar surface was electronegative, due to the ionization of oxygen-containing functional groups, such as hydroxyl (-OH) and carboxyl (-COOH) groups. Solution pH had only a weak influence on TC adsorption; neutral conditions favored adsorption. The adsorption kinetics and isotherms were represented well by the pseudo-second-order and Freundlich models, respectively. The chemical multilayer adsorption may play an important role in TC adsorption, which was a spontaneous endothermic reaction. The adsorption process occurred more easily after KOH activation and the adsorption capacity of biochar improved by more than 20 times. These results indicate that preparing reed-derived biochar using KOH activation is an effective way to reduce pollution and utilize a waste resource.