Abstract A very selective leach for an assorted material stream such as the PCB dust is a vital process step to achieve less complex downstream processing. Thermodynamically, oxidative ammonia leaching should complex copper and zinc relatively selectively from the dust compared to other reagents regime, but investigation under optimum kinetic conditions studied and used herein revealed process design realities. For 75–106 μm dust size, 2 M NH4OH, 17.5 M H2O2, 1 atm. Pressure and 400 rpm in a stirred reactor, Cu and Zn recoveries were 92% and 50%, while activation energies evaluated within 283–313 K gave 47.39 kJ/mol and 33.12 kJ/mol under chemical and mixed control reaction mechanisms respectively. Though, Zn(NH3)42+ formation has more negative free energy than Cu(NH3)42+ formation, yet zinc recovery is much lower. The low recovery was attributed to the dust particle morphology with zinc occuring as alloys inert to this reagent condition.

中文翻译：

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印制电路板物理加工粉尘氧化氨浸出铜、锌的动力学分析

摘要 对各种材料流（例如 PCB 粉尘）进行非常有选择性的浸出是实现不那么复杂的下游加工的关键工艺步骤。在热力学上，与其他试剂方案相比，氧化氨浸出应相对选择性地从粉尘中络合铜和锌，但在本文研究和使用的最佳动力学条件下进行的研究揭示了工艺设计的现实。对于 75–106 μm 粉尘尺寸，2 M NH4OH、17.5 M H2O2、1 atm。在搅拌反应器中的压力和 400 rpm 下，Cu 和 Zn 的回收率分别为 92% 和 50%，而在化学和混合控制反应机制下，在 283-313 K 范围内评估的活化能分别为 47.39 kJ/mol 和 33.12 kJ/mol。虽然 Zn(NH3)42+ 的形成比 Cu(NH3)42+ 的形成具有更多的负自由能，但锌的回收率要低得多。