文档介绍：Removal of tin from alkaline zinc solution by zinc
powder cementation
Jiang Jiachao, Chen Wei, Hu Xiang, Zhao Youcai
State Key Laboratory of Pollution Control and Resource Reuse
Tongji University
Shanghai, China
E-mail: jiangjiachao@

Abstract— In this work, the influence of tin on electrowinning of zinc surface as the current density increases makes alkaline
zinc from alkaline solution was observed. Tin changed the zinc electrowinning possible, in which hydrogen evolution on
deposited zinc pact form, made zinc hardly peel off from the cathode surface is even more impeded than the one in
cathodes and should be separated from alkaline electrolyte acidic electrowinning. A higher current efficiencies can thus
before zinc electrowinning. Experiments for Sn removal from be reached than in acidic electrowinning [8,9].
alkaline zinc solution by several chemical methods were tested. It In our previous work [9], the alkaline process has been
was found that Sn can be cemented quantitatively from alkaline applied essfully for zinc recovery from brass smelting ash
zinc solution by the addition of zinc powder at 95 ℃, 500 rpm at industrial scale. However, impurities in alkaline leach
with Zn/Sn molar ratio 6. The resulted Sn concentration in solution were various and depending on raw sources. Besides
solution can be lower than 50 mg/L by zinc powder c