Study on the Adsorption of Ofloxacin in Water by

In this paper, Canna indica was pyrolyzed to produce the original biochar (BC) and modified by HNO3 and KOH (HBC and KBC). The adsorption kinetics and isotherm for ofloxacin (OFLX) removal by three biochars were studied, and the effects of pH value and dosage on the adsorption effect were also investigated. The results showed that the quasi-second-order kinetic model could describe the OFLX adsorption processes by BC, HBC and KBC, which was mainly chemical adsorption. The adsorption isotherms of three biochars were consistent with the Freundlich model. The adsorption by BC was greatly affected by pH change, and its adsorption capacity decreased with the increasing of pH, while the HBC and KBC were not sensitivity. With the increase of biochars dosage, the adsorption capacity of OFLX for the three kinds of biochar presented a trend of increasing first and then gradually stabilizing.