環境

[2P0115-20-04] Effects of Al powder addition on Pb removal from zinc leach residues in acidified chloride solution (発表者：博士課程)

○Silwamba Marthias^1,3、Hashizume Ryota¹、Fukushima Tomoki¹、Tabelin Carlito. B²、Park Ilhwan ¹、Jeon Sanghee¹、Banda Kawawa³、Chirwa Meki³、Nyambe Imasiku³、Ito Mayumi¹、Hiroyoshi Naoki¹ (1. Hokkaido University、2. The University of New South Wales、3. The University of Zambia)

キーワード：Leaching、Cementation、Zinc leach residues、Lead

Zinc leach residues (ZLRs), the solid waste produced during zinc hydrometallurgical extraction processes, are widely known to be hazardous to the environment because they contain toxic heavy metals like lead (Pb). In this study, Pb removal from ZLRs that were produced and dumped more than 35 years ago in Kabwe, Zambia, was investigated. ZLRs was leached in NaCl-HCl solution of different compositions with and without Al powder addition. In case when ZLRs were leached with Al powder, Pb were extracted from ZLRs into leaching solution and it was sequestered from the leaching pulp via cementation with Al powder. Cemented Pb agglomerated and was separated from the leaching pulp by sieving. Compared to Pb removal without Al powder, the addition of Al powder drastically increased Pb removal from 2.8 to 36% for 0.05 M HCl and 3.5 to 68% for 0.1 M HCl solution containing 0.5 M NaCl.