微波辅助浸取废弃电路板中铅锡锑

浸取废弃电路板中铅、锡、锑等金属的主要方法是利用传统加热辅助湿法冶金, 但通常耗时长、效率低。为了解决这一问题, 本文提出了一种用微波代替传统加热方式、辅助湿法冶金浸取金属的新方法。结合氧化熔炼技术的原理, 采用微波辐射废弃电路板粉末, 探索了以下几个因素对金属浸出率的影响:氧化浸取过程中的NaNO₃用量、NaOH用量、微波功率、微波辐射时间、Na₂S浸取过程中的水用量、微波辐射时间。在实验研究基础上得到的最佳工艺条件为:氧化浸取过程中NaNO₃与金属粉末的质量比为3, NaOH与金属粉末的质量比为5, 微波功率为800W, 微波辐射时间为6min;Na₂S浸取过程中液固比为3, 微波辐射时间为20s;此时铅、锡、锑的浸出率分别是92.37%、94.4%、88.13%。较之传统氧化熔炼技术, 该方法反应速率加快, 金属浸出率提高, 产生废液少, 具有方便高效、绿色环保的特点。

Leaching of Pb,Sn and Sb from waste printed circuit board by microwave-assisted method

The main method of leaching of lead, tin, antimony from waste printing circuit board is traditional heating assisted hydrometallurgy, but long time and low efficiency limit its application. In order to solve this problem, this paper proposed a microwave-assisted hydrometallurgy in metal leaching. The research adopted microwave radiation waste circuit board powder and explored effects of several factors on the metals leaching rate, including NaNO₃ and NaOH dosage, microwave capacity and microwave time in the oxidizing leaching process, water dosage, microwave time in the Na₂S leaching process. The experimental results showed that the optimum reaction conditions were:mass ratio of NaNO₃ and NaOH to metal powder was 3:5, radiation for 6min under microwave power was 800W in the oxidizing leaching process;liquid-solid ratio was 3, and radiation time for Na₂S leaching process was 20s. The leaching rate of Pb, Sn and Sb was 92.37%, 94.4%, 88.13% respectively. Compared with the traditional oxidation smelting technology, this new method had high reaction speed and leaching rate, produced less waste liquor, convenient and efficient, environmental friendly.