【Paper】
Distribution Behavior of Heavy Metal between Molten Chlorides and Slag
Etsuro Shibata*, Kazuhiro Fukuda*†, Takashi Nakamura*, Takeshi Ari**†, Tomio Takasu** and Hideyuki Itou**
* Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
** Department of Materials Science and Engineering, Kyushu Institute of Technology
*† Kobe Steel, Ltd.
**† Japan Casting & Forging Corp.
† Correspondance should be addressed to Etsuro Shibata:
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
（1-1 Katahira, 2-Chome, Aobaku, Sendai, Miyagi, 980-8577 Japan）

Abstract
Understanding the behavior of heavy metals in an ash melting furnace is important to avoid heavy metal contamination in recycled materials and facilitate the metals' effective recovery. The volatilization behavior of heavy metals is strongly related to distribution of molten salts and slag. This study measured distribution ratios of heavy metals for molten salt and slag as（LM＝（mass％M）salt/（mass％M）slag ,M＝Pb, Zn）using a hermetic or open cell. Heavy metals were vaporized with an almost fixed distribution between molten salt and slag. Distribution ratios of Pb and Zn decreased with increased basicity of slag. The chlorinated reaction of Pb and Zn by CaCl2 can explain the mechanism of this effect. Total chlorine content in slag increased with increased basicity of slag. This fact is attributable to the exchange reaction between chlorine ion in molten salt and oxygen ion in slag.

Key words: molten salt, slag, heavy metal, ash melting process, distribution ratio