湿式ボールミル法を用いたPLZTセラミックスからの鉛の回収

抄録

The recovery of lead from PLZT ((Pb_0.9La_0.1)(Zr_0.52Ti_0.48)O₃) ceramics was investigated by the wet ball-mill method using 1.4-11.3MH₂SO₄ aqueous solutions. The wet ball-mill treatment was performed in a pot mill apparatus at room temperature for 0-72h with a rotational speed fixed at 300rpm. It was found by X-ray diffraction (XRD) analysis that the treatment time required for completely converting from crystalline PLZT to PbSO₄ nano-particles could be shortened with increasing H₂SO₄ concentration. According to inductively-coupled-plasma atomic-emission (ICP-AES) analysis of the components dissolved into the solution, the amount of dissolved zirconium and titanium ions increased with increasing treatment time. The dissolution of both components was closely related to the disintegration behavior of crystal structure of PLZT ceramics. The amount of dissolved lead ion was about 0.1% of the lead included in the non-treated PLZT under the whole experimental conditions, while that of lanthanum ion was below 60%. The amount of lanthanum ion dissolved into the solution was dependent on the concentration of H₂SO₄ aqueous solution used for treatments. These results indicated that the wet ball-mill method gave a yield of PbSO₄ as high as 99%, and the purity of the collected PbSO₄ from PLZT ceramics was about 91-95%.