Study on adsorption of Cr, Fe, Ni from stainless steel pickling wastewater by activated carbon

摘要

The thermodynamics and kinetics on adsorption of Cr, Fe and Ni by activated carbon from stainless pickling wastewater are studied. The results show that the adsorption capacity of Cr, Fe and Ni are 8.198, 1.629 and 2 mg/g, respectively. The Freundlich isotherm model can fit the multi-component system better than the Langmuir isotherm, while the Langmuir - Freundlich equation is the best choice to fit them. The equilibrium times are 120, 60, 90 min, and the pseudo-second-order equation can fit the adsorption well. The results indicate that Cr is mainly chemically adsorbed on activated carbon with ion exchange adsorption, while physical adsorbption dominants the adsorption of Fe, and Ni is mainly of ion exchange adsorption.