The thermodynamics of metal ions from stainless steel pickling wastewater on strong-acid cation exchange resin

The adsorption behavior of Cr
³⁺
and Fe
³⁺
on 001×7 strong-acid cation exchange resin was studied with the static method, respectively getting Adsorption Isotherms of Resin 001×7 for Cr
³⁺
and Fe
³⁺
. The experimental results show that, in the studied concentration range, the equilibrium adsorption data of Cr
³⁺
fit to Langmiur isotherms, while Fe
³⁺
fitting to Frendlich isotherms. Kinetic analysis show that the adsorption rate of Cr
³⁺
is mainly governed by liquid film diffusion and the rate of Fe
³⁺
is governed by Particle diffusion. In addition, the thermodynamic parameters were obtained from analyzed dynamics data and thermodynamic function. The conclusion indicates that the adsorption gets more orderly and is an exothermic process running spontaneously, so that higher temperature is bad for the reaction.