Abstract
In the presence of co-adsorbates, activated carbon can adsorb mercury in water. In this paper, organic ligands and halogenide ions which can form non-charged or anionic complexes with Hg2+ were used as co-adsorbates and removal conditions of Hg (II) ion were examined using three kinds of activated carbon (prepared from coal). In the presence of organic co-adsorbates (L-Cysteine, Picolinic acid, 8-Hydroxy-quinoline), maximal removal of Hg (II) ion was obtained at neutral pH and at the concentration of 10-3mol/l Picolinic acid. When KBr or KI was used as a co-adsorbate, maximal removal was obtained at slightly acidic condition and at the concentration of 10-2mol/l KBr or 10-3mol/l KI. The removal of Hg (II) ion by activated carbon was interfered with by the existence of chelating agents such as EDTA and peptone, but Hg (II) ion was removed effectively by addition of KBr or KI When KI (10-3mol/l) was added to the Hg (II) solution (1 mg/l as Hg2+) containing 1 mmol/l EDTA (pH 6.5) or 5g/l peptone (pH 2.6) and the solution was treated with a column packed with 2g of Mitsubishi activated carbon, mercury concentration in effluent (31) was reduced to 1.6 (EDTA) or 6.8 (peptone), μg/l.
