Removal of heavy metal ions in the presence of the biodegradable complexing agent of EDDS from waters

In the investigations three polystyrene divinylbenzene ion exchangers with different degrees of basicity of the functional groups for removal of heavy metal ions from aqueous solutions were used. The experiments were conducted in the multicomponent systems in the presence of the complexing agent – ethylenediaminedisuccinic acid (EDDS) and the accompanying ions (Cl−, NO3- and SO42-). Their related absorption behaviors such as thermodynamic equilibrium, pH effect and the Langmuir and Freundlich models to evaluate the experimental data are discussed in this paper. As shown for the ion exchanger Lewatit MonoPlus M 800 the values of monolayer capacity in the multicomponent system including Cr(VI), Cu(II), Zn(II) and EDDS are 111.11 mg/g, 120.48 mg/g and 116.28 mg/g for Cr(VI), Cu(II) and Zn(II) ions, respectively. With respect to the parameters KL and q0 the studied elements can be ordered Cu(II) > Zn(II) > Cr(VI). According to the results, this resin can be a promising reagent for disposal of industrial wastes.

• Ion exchangers with different basicity of functional groups were used in removal of heavy metals from solutions. • The different factors affecting the metal ions loading onto Lewatit MonoPlus M 800. • The pH, contact time and system composition were studied.