Chen Mengjun, Huang Jinxiu, Ogunseitan Oladele A, Zhu Nengming, Wang Yan-min
Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang 621010, China.
Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang 621010, China.
Waste Manag. 2015 Jul;41:142-7. doi: 10.1016/j.wasman.2015.03.037. Epub 2015 Apr 11.
Waste printed circuit boards (WPCBs) are attracting increasing concerns because the recovery of its content of valuable metallic resources is hampered by the presence of hazardous substances. In this study, we used ionic liquids (IL) to leach copper from WPCBs. [BSO3HPy]OTf, [BSO3HMIm]OTf, [BSO4HPy]HSO4, [BSO4HMim]HSO4 and [MIm]HSO4 were selected. Factors that affect copper leaching rate were investigated in detail and their leaching kinetics were also examined with the comparison of [Bmim]HSO4. The results showed that all six IL acids could successfully leach copper out, with near 100% recovery. WPCB particle size and leaching time had similar influences on copper leaching performance, while IL acid concentration, hydrogen peroxide addition, solid to liquid ratio, temperature, showed different influences. Moreover, IL acid with HSO4(-) was more efficient than IL acid with CF3SO3(-). These six IL acids indicate a similar behavior with common inorganic acids, except temperature since copper leaching rate of some IL acids decreases with its increase. The results of leaching kinetics studies showed that diffusion plays a more important role than surface reaction, whereas copper leaching by inorganic acids is usually controlled by surface reaction. This innovation provides a new option for recovering valuable materials such as copper from WPCBs.
废弃印刷电路板（WPCBs）正引起越来越多的关注，因为其所含的有价值金属资源的回收受到有害物质的阻碍。在本研究中，我们使用离子液体（IL）从废弃印刷电路板中浸出铜。选择了[BSO3HPy]OTf、[BSO3HMIm]OTf、[BSO4HPy]HSO4、[BSO4HMIm]HSO4和[MIm]HSO4。详细研究了影响铜浸出率的因素，并与[Bmim]HSO4进行比较，考察了它们的浸出动力学。结果表明，所有六种离子液体酸都能成功地浸出铜，回收率接近100%。废弃印刷电路板的粒径和浸出时间对铜的浸出性能有相似的影响，而离子液体酸浓度、过氧化氢添加量、固液比、温度则表现出不同的影响。此外，含HSO4(-)的离子液体酸比含CF3SO3(-)的离子液体酸更有效。这六种离子液体酸与常见无机酸表现出相似的行为，但温度除外，因为某些离子液体酸的铜浸出率会随温度升高而降低。浸出动力学研究结果表明，扩散比表面反应起更重要的作用，而无机酸浸出铜通常受表面反应控制。这一创新为从废弃印刷电路板中回收铜等有价值材料提供了新的选择。
