废提款机线路板铜粉脱除杂质金属

Removal of impurity metals from waste printed circuit board copper powder of cash machine

废提款机线路板铜粉通常采用火法炼铜系统提取有价金属,本文提出两段浸出方法分离废提款机线路板铜粉中的杂质金属,以消除对火法炼铜系统的危害,并为火法炼铜提供了优质的原料。首先,采用盐酸处理废提款机线路板铜粉,脱除其中的铝,脱铝渣再分别采用盐酸控电位氧化浸出,或碱性加压氧化浸出分离回收铅和锡。结果表明:盐酸浸出过程中96.11%的铝被选择性脱除;脱铝渣采用盐酸控电位氧化浸出,铅和锡的浸出率分别为91.12%和94.69%;碱性加压氧化浸出处理脱铝渣,铅和锡的浸出率分别为86.28%和96.96%;在废提款机线路板破碎过程中,由于机械撞击力使杂质金属与铜相互包裹,难以充分溶解,导致铅和锡脱除不完全。

Waste printed circuit board(WPCB) copper powder of cash machine is usually extracted valuable metals by pyrometallurgical copper smelting system.In this paper,a two-stage leaching method was proposed to separate the impurity metals in the WPCB copper powder and provided high-quality raw materials for copper smelting.Firstly,the WPCB copper powder was leached by hydrochloric acid to remove aluminum,the dealuminated residue were separated and recovered lead and tin by hydrochloric acid controlled potential oxidation leaching or alkaline pressure oxidation leaching.The results show that 96.11% aluminum is selectively removed by hydrochloric acid leaching.The dealuminated residue is leached by hydrochloric acid controlled potential oxidation,the leaching rates of lead and tin are 91.12% and 94.69%,respectively.The dealuminated residue is treated by alkaline pressure oxidation leaching,the leaching rates of lead and tin are 86.28% and 96.96%,respectively.In the breaking process of WPCB,due to the mechanical impact force,the impurity metal and copper are bonded to each other,which is difficult to fully dissolve,resulting in incomplete removal of lead and tin.