摘要

Aerobic granular sludge was prepared as adsorbent to remove Cu2+ from aqueous solution. Different initial pH values, initial Cu2+ concentrations, adsorbent doses, and temperatures on Cu2+ adsorption were evaluated. Three kinds of adsorption isotherms (Langmuir model, Freundlich model, and Redlich-Peterson model) were investigated; the results indicated that equilibrium was well described by Langmuir isotherm, predicting the adsorption of Cu2+ on aerobic granules was a monolayer adsorption. The equilibrium kinetic adsorption data were fitted to the pseudo-second-order kinetic equation. Furthermore, the sorption of Cu2+ was controlled primarily by intraparticle diffusion combined with the kinetics process with Energy-dispersive X-ray spectroscopy (EDS) analysis. Parameters of adsorption thermodynamic suggested that the interaction of Cu2+ adsorbed by aerobic granules was spontaneous and exothermic. Moreover, the Fourier transform infrared spectroscopy (FTIR) results indicated that such active groups -OH, -COOH, and -NH2 were involved in Cu2+ adsorption. EDS and FTIR revealed that ion-exchange and surface complexation mechanism coexisted during the adsorption process. Zeta potential analysis demonstrated inner-sphere adsorption happened for Cu2+ adsorption on aerobic granules.

  • 出版日期2015-5-15