(中南大學(xué) 冶金與環(huán)境學(xué)院,長沙 410083)
摘 要: 研究了在(CH3)3COOH-NaOH體系中,廢棄電路板焊錫的錫和鉛的分離富集行為。系統(tǒng)分析了反應(yīng)溫度、溶液組成、NaOH濃度、(CH3)3COOH滴加速度等因素對焊錫浸出效果的影響,得到最佳工藝參數(shù)如下:在溶液組成為85%的氫氧化鈉與15%的(CH3)3COOH,反應(yīng)溫度為70 ℃條件下,當氫氧化鈉溶液初始濃度為5 mol/L,(CH3)3COOH滴加速度為2.4 mL/min,浸出時間為20 min時,錫的浸出率為96.21%,鉛的浸出率為92.36%。往退錫后液中加入理論量1.5倍的Na2S?9H2O,鉛的沉淀率為98.79%,可制得純度為99.23%的PbS產(chǎn)品;往沉淀后液中加入理論量2.5倍的Ca(OH)2,錫的沉淀率達到93.21%,熱處理后可得到SnO2產(chǎn)品,產(chǎn)品符合GB/T 26013—2010標準。
關(guān)鍵字: 廢電路板;焊錫;(CH3)3COOH;NaOH
(School of Metallurgy and Environment, Central South University, Changsha 410083, China)
Abstract:In the (CH3)3COOH-NaOH system, the separation and enrichment of tin and lead in solder in waste circuit board are studied. The impacts of leaching temperature, solution composition, NaOH concentration and dropping speed of (CH3)3COOH on solder extraction were systematically analysed. The optimum parameters for leaching are as follows: under the conditions of the solution consisting 85% of NaOH and 15% of (CH3)3COOH and leaching temperature of 70 ℃, when NaOH concentration is 5 mol/L, dropping speed of (CH3)3COOH is 2.4 mL/min and leaching time is 20 min, the leaching rates of lead and tin reach 98.79% and 99.23% respectively. After adding 1.5 times the theoretical amount of Na2S 9H2O to the solution, the precipitation rate of lead reaches 98.79%, the purity of 99.23% of PbS products are obtained. After adding 2.5 times the theoretical amount of Ca(OH)2 to the solution, the precipitation rate of tin reaches 93.21%, SnO2 products can be obtained after the heat treatment, which meet the GB / T 26013—2010 standard.
Key words: waste printed circuit board; solder; tert-butyl hydroperoxide; sodium hydroxide


