Stabilization of toxic ions with manganese-modified sorbents

Abstract

In this study, a possible improvement of adsorption properties due to the manganese (Mn) modification was tested on natural zeolites. Modification method consisted of the synproportionation reaction of KMnO₄ and (CH₃COO)₂Mn and deposition of resulting MnO_x on the adsorbent surface at elevated temperature. For the modification the natural clinoptilolite from Nižný Hrabovec was used. The sorbent was kept in contact with the solution of metal ion (Zn²⁺, Cd²⁺, Pb²⁺ and Al³⁺) with concentration of 0.5 mmol L⁻¹ for 24 hours. Then the decrease in the concentration of polluting ion was measured. The results were compared with commercial sorbents. The modified zeolite achieved 10 % better adsorption efficiency than natural zeolite for all ions. The adsorption efficiency of the prepared sorbent was approximately 30 % lower compared to the commercial adsorbents. The same modification method was also applied to waste building sludges and prepared materials were tested for metal ions capture. In this case, the modification of brick dust (CO) was most promising for Al³⁺ adsorption, where the efficiency increased by 34 %.