Removal of Cr(III) Ions from Wastewater by Using Ligand Adsorption

摘要

Cr(III) metal ions, which are found frequently in leather industry wastewater, cause very serious problems especially for biological wastewater treatment systems. Therefore, it is necessary to selectively remove this heavy metal ion from wastewater. Removal of heavy metal ions from wastewater before treatment is an approach that improves treatment performance. The purpose of this study was the removal of Cr(III) ions from the leather industry wastewater using amino oxime ligand. Different adsorption experiments were investigated with different environmental parameters in the removal of Cr(III) ions, which are serious problems in wastewater of the leather industry, with amino oxime, and optimum values were determined. These parameters include Cr(III) ions, amino oxime concentrations, solution pH, temperature, and mixing speed. Adsorption capacities of amino oxime were increased while the initial Cr(III) ion concentration, mixing speed, and solution pH increased, whereas adsorption capacities decreased by increasing the concentration of amino oximes. The adsorbent (amino oxime) concentration should be kept at 3 g/L to achieve a removal yield of >89% at a concentration of 100 mg/L initial Cr(III) ion. When the amino oxide concentration was 0.25 g/L, the maximum adsorption capacity of 152 mg Cr(III)/g was reached.