重金属フェライト化処理の通気撹拌条件

抄録

Effects of θ_e, needed for Fe (II) oxidation with air, initial molar ratio Fe²⁺/M²⁺ (M : Zn, Cd and Mn) and reaction temperature on ferritization of heavy metal ions were studied by stability of heavy metal, obtained by leaching test of ferrite suspension at pH 3-3.5, and yield of Fe₃O₄ (3·Fe²⁺/Total-Fe).
θ_e≥1.5 h, θ_e is controled by the conditions of aeration and mixing speed, the stability and the yield of Fe₃O₄ were not effected by θ_e, but they were increased with Fe²⁺/M²⁺ and reaction temperature.
Sedimentation of these ferrites was also studied for the separation of sludge from the treated water. Settling velocity of ferrite became faster, when the ratio of spinnel formation is over 0.5-0.6.