process for the production of Zn powder by alkaline treatment of brass smelting ash at industrial scale
In this paper, an industrial-scale alkaline process for the production of Zn powder using brass smelting ash as raw material was presented. It was suggested that the brass smelting ash be leached with 230 g/L NaOH solution at 80 ℃ for 90 min at a phase ratio of 15. The maximum extraction of Zn and Pb can be reached at 96-99％ and 90-95％, respectively. After Pb was separated selectively and quantitatively by sodium sulfides precipitation, the solution was subjected to electrolysis for the production of zinc powder with a current density of 800-1000 A/m2 at 40-50 ℃, using stainless steel electrodes as anode and titanium alloy as cathode. The specific energy for the Zn electrolysis was around 2.7-3.1 kWh/kg Zn. Additional operations including Zn powder filtration, washing, desiccation, sieving and milling etc. were required, and the production of Zn powder with a purity over 96％ can be obtained finally. Compared with the classical acidic-air pulverization production process of Zn powder, about 10-15％ energy can be saved by the alkaline process.
zinc powder brass smelting ash alkaline leach electrowinning industrial scale
Jiang Jiachao Zhao Youcai
State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai,China
国际会议
北京
英文
1-4
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）