(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長沙 410083)
摘 要: 研究低溫堿性熔煉過程中廢棄電路板多金屬粉末有價金屬的元素行為，在熔煉過程中，Sn、Pb、Zn等兩性金屬與堿及氧化劑反應(yīng)生成相應(yīng)的可溶性堿金屬鈉鹽，通過水浸實現(xiàn)與其他金屬分離，取得良好的轉(zhuǎn)化效果。探索了氧化劑用量、堿用量、熔煉溫度、熔煉時間、液固比、浸出溫度、浸出時間等7個因素對金屬轉(zhuǎn)化率的影響，優(yōu)化得到較為適宜的熔體組成與工藝條件：熔體中多金屬粉末、NaNO3、NaOH的質(zhì)量比為1:3.0:3.6，773 K(500 ℃)條件下熔煉90 min后，冷卻粉碎，加水至液固比為9，加熱至313K(40℃)浸出60min。在此優(yōu)化工藝條件下，各金屬的轉(zhuǎn)化率依次為Sn 95.93%、Zn 96.63%、Pb 91.21%和Sb 24.68%。
關(guān)鍵字: 廢棄電路板；兩性金屬；低溫堿性熔煉；轉(zhuǎn)化率
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The elemental behavior of valuable metals in multi-component metal powder (MMP) originated from waste printed circuit board (PCB) was investigated. The applied method of low-temperature alkaline smelting can convert amphoteric metals Sn, Pb and Zn into soluble sodium salts that can be separated from the other metals in leaching process efficiently. The effects of oxidant and alkaline addition, smelting temperature and time, liquid-solid ratio, leaching temperature and time on the metal conversion rate (R) were investigated. The composition of melt and optimum conditions are obtained as mass ratio of MMP, NaNO3 and NaOH being 1:3.0:3.6, smelting for 90min at 773 K (500 ℃), leaching for 60min at 313 K (40 ℃) in water solution (L/S=9). The conversion rates of the metals are as follows: Sn 95.93%, Zn 96.63%, Pb 91.21%, Sb 24.68%.
Key words: waste printed circuit board; amphoteric metal; low-temperature alkaline smelting; conversion rate
