FEASIBILITY OF TWO BULGARIAN MEDICINAL PLANT MATERIALS FOR REMOVAL OF Cu2+ IONS FROM AQUEOUS SOLUTIONS

In the present study the feasibility of two biomaterials based on Mentha spicata L. (denoted as MS) and Ruta graveolens L. (denoted as RG) from the group of ethereal oil plants for the removal of Cu2+ ions from aqueous solution was investigated. Batch experiments were performed to evaluate the effect of contact time, acidity and initial metal concentration on Cu2+ removal from aqueous solutions. Pseudo-first order, pseudo-second order and intraparticle diffusion models were used to analyse kinetic data. Desorption studies have also been performed. Equilibrium experimental data were fitted to linear Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. Maximum adsorption capacities were calculated and it was concluded that the material MS showed better adsorption properties for Cu2+ ions in comparison with RG. Nevertheless the results showed that both MS and RG could be used as effective biosorbents for the removal of copper ions from aqueous media.