Yang Yuantao, Wang Zhaoyi, Wang Xuanbing, Xu Wanli, Yuan Haibin, Liu Qingdong, Xu Ruidong, Yang Linjing
State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China.
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China.
Materials (Basel). 2025 Sep 2;18(17):4122. doi: 10.3390/ma18174122.
Current electrolytic refining processes for crude solder commonly employ fluosilicic acid (HSiF) as the electrolyte with bone glue and β-naphthol additives yet suffer from poor electrolyte stability, coarse cathode crystallization, low current efficiency, and high energy consumption, adversely affecting product quality and economic viability. In order to solve these limitations, electrochemical techniques, XRD, SEM, and ICP-OES were used to study the effects of gelatin and sodium lignosulfonate on the deposition overpotential and cathode morphology, as well as the effects of process parameters on current efficiency and energy consumption. A novel approach was developed using an HSiF system enhanced by gelatin and sodium lignosulfonate for crude solder refining. After optimization, 120 h electrolysis achieved a current efficiency >97.8%, smooth/dense cathode surface, average cell voltage of 0.24 V, and energy consumption of 98.15 kWh/t. Efficient deposition of 81.2% Sn and 75.2% Pb on the cathode was realized, while >93.3% of Sb, Bi, Ag, Cu, and As were enriched in anode slime to facilitate valuable metal recovery, and >90.6% of In/Al concentrated in the electrolyte enabled effective Sn-Pb impurity separation. This study provides theoretical and technical foundations for advancing sustainable and economical electrolytic refining of crude solder.
目前用于粗焊料的电解精炼工艺通常采用氟硅酸（HSiF）作为电解液，并添加骨胶和β-萘酚，但存在电解液稳定性差、阴极结晶粗糙、电流效率低和能耗高的问题，对产品质量和经济可行性产生不利影响。为了解决这些限制，采用电化学技术、XRD、SEM和ICP-OES研究了明胶和木质素磺酸钠对沉积过电位和阴极形态的影响，以及工艺参数对电流效率和能耗的影响。开发了一种使用明胶和木质素磺酸钠增强的HSiF体系进行粗焊料精炼的新方法。经过优化，120小时电解实现了电流效率>97.8%，阴极表面光滑/致密，平均槽电压为(0.24V)，能耗为(98.15kWh/t)。在阴极上实现了(81.2%)的Sn和(75.2%)的Pb的高效沉积，同时>93.3%的Sb、Bi、Ag、Cu和As富集在阳极泥中以促进有价金属回收，>90.6%的In/Al集中在电解液中实现了有效的Sn-Pb杂质分离。本研究为推进粗焊料可持续和经济的电解精炼提供了理论和技术基础。
