The circularity represents the key strategy of the modern economy, where the waste becomes a raw material, ready to be reprocessed for a second life. In this context, the main aim of the present work was the development of a sustainable process for the recovery of Cu and Zn from end-of-life printed circuit boards (PCBs). The exploitation of this hazardous waste produces a double effect: the recovery of metals, suitable for the current metal market, and the avoided disposal of scraps produced worldwide. The process allowed to exceed the limits of several approaches reported in the literature, mainly due to the highest consumptions (both energy and raw materials) and the loss of Zn content. The best identified conditions, suitable for the treatment of both chemical and bio- leach liquor included: the Fe precipitation with sodium hydroxide, followed by the Cu cementation with Zn (Zn/Cu molar ratio of 1.1) and a final Zn precipitation with oxalic acid (O.A./Zn molar ratio of 1.5). The metals showed recovery efficiencies higher than 95% and purities up to 95%. An efficient recirculation system contributes to the sustainability growth, as confirmed by the carbon footprint assessment, towards the implementation of a zero waste treatment. Future perspective should include the further exploitation of the residue, rich in precious metals.

循环性代表了现代经济的关键策略，在这种策略中，废物成为原材料，可以进行第二次处理。在这种情况下，当前工作的主要目的是开发一种从报废印刷电路板（PCB）回收铜和锌的可持续工艺。开采这种有害废物会产生双重影响：回收适合当前金属市场的金属，并避免处理全世界产生的废料。该工艺可以超出文献报道的几种方法的极限，这主要是由于最高的消耗量（包括能源和原材料）以及锌含量的损失。确定的最佳条件，适用于化学和生物浸出液的处理，包括：用氢氧化钠沉淀铁，然后用Zn固结铜（Zn / Cu摩尔比为1.1），最后用草酸沉淀Zn（OA / Zn摩尔比为1.5）。这些金属的回收效率高于95％，纯度高达95％。正如碳足迹评估所证实的那样，有效的再循环系统有助于实现可持续发展，以实现零废物处理。未来的前景应包括进一步开采富含贵金属的残渣。迈向零废物处理。未来的前景应该包括进一步开采富含贵金属的残渣。迈向零废物处理。未来的前景应包括进一步开采富含贵金属的残渣。