Equilibrium of metals with iminodiacetic resin in binary and ternary systems

Experiments of binary and ternary ion exchange equilibrium of heavy metals and sodium were carried out in a complexing iminodiacetic resin Lewatit TP 207. First, binary equilibrium data were obtained at different temperatures and ionic strength and fixed to models considering two different ion excha nge stoichiometries. For ternary equilibrium data, two distinct simple mode ls were applied. One to be applied to systems showing very different select ivity for the metals (for instance, Cu2+/Co2+/Na+) and the other for system s with similar selectivity for the metals (such as Zn2+/Co2+/Na+). The tern ary equilibrium data obtained is presented in this work and fitted using th e two above mentioned models. These models allow us to obtain the equilibri um parameters for binary and ternary system to be used in the design of equ ipment using this iminodiacetic resin.