Sulfadiazine removal from aqueous solutions by hydrous manganese oxides

摘要

The adsorption behavior of sulfadiazine (SDZ) onto hydrous manganese dioxide (HMO) is systematically investigated in this study. SDZ removal is highly pH dependent and ionic strength has slightly effect on the uptake of SDZ. The Webber-Morris equations model shows that SDZ adsorption by HMO is controlled jointly by the film-diffusion and intraparticle-diffusion. The adsorption isotherms at varied temperatures are well described by Langmuiir model, and thermodynamic parameters (ΔH>0, ΔS>0 and ΔG<0) reveal that the adsorption of SDZ on HMO is spontaneous and endothermic process. The uptake process of SDZ by HMO is mainly ascribed to the hydrogen bonding between the nitrogen (N) of aniline and the surface hydroxyl groups of HMO.