Superfine copper particles could be directly prepared from waste printed circuit boards by slurry electrolysis. Meanwhile, copper fractal growth could be observed. To better understand this phenomenon, the factors that affect copper dendrites in a point-cathode system were discussed in detail. These results showed that the fractal degree of copper dendrites increased as the increase of applied voltage and the decrease of copper sulfate and gelatin concentrations. Sodium lauryl sulfate and hydrochloric acid concentrations could not significantly impact the fractal degree of copper dendrites, while gelatin concentration could. The minimum copper fractal dimension was 1.069 when gelatin and copper sulfate concentration was 120 mg/L and 0.1 mol/L, respectively with an applied voltage of 11 V. Moreover, the results diffusion-limited aggregation model demonstrated that particle translational speed, particle numbers and binding probability significantly affected copper dendrite patterns. The scanning electron microscopy results indicated that the three additives greatly affected the refinement of the copper crystal. These findings contribute to enrich the theoretical study on metals recovery from e-waste by slurry electrolysis.

可以通过废液电解直接从废印刷电路板制备超细铜颗粒。同时，可以观察到铜的分形生长。为了更好地理解这种现象，详细讨论了影响点阴极系统中铜枝晶的因素。这些结果表明，随着施加电压的增加以及硫酸铜和明胶浓度的降低，铜枝晶的分形度增加。月桂基硫酸钠和盐酸的浓度不会显着影响铜枝晶的分形度，而明胶的浓度会影响分枝度。当明胶和硫酸铜的浓度分别为120 mg / L和0.1 mol / L且施加电压为11 V时，最小铜分形维数为1.069。扩散受限聚集模型的结果表明，粒子的平移速度，粒子数量和结合概率显着影响铜枝晶的模式。扫描电子显微镜结果表明，三种添加剂极大地影响了铜晶体的细化。这些发现有助于丰富有关通过浆料电解从电子废物中回收金属的理论研究。