用氯盐体系从印刷电路板上退锡试验研究

Stripping of Tin From Printed Circuit Board in Chloride System

研究了采用氯盐体系对印刷电路板(PCB)退锡,退锡后液以隔膜电积法回收锡。通过单因素条件试验确定退锡优化条件。结果表明:在45℃条件下,用Sn^(4+)质量浓度60 g/L、盐酸浓度5 mol/L的溶液为退锡剂,可在2 min内退去PCB上的锡镀层;退锡液经均相膜隔膜电积10 h,阳极室退锡后液中Sn^(4+)质量浓度达58.6 g/L,可作为退锡剂循环使用,阴极锡锭纯度99.9%,可直接用于制备PCB,锡得到循环使用。

A novel process for stipping tin from PCB in a chlorine system and recovering tin from stipping tin solution by membrane electrodeposition wer studied.The optimum conditions were obtained by single factor experiment.The results show that the tin layer can be stripped in less than 2 min under the condition of 45℃,Sn^(4+)mass concentration of 60 g/L,hydrochloric acid concentration of 5 mol/L.Moreover,after membrane electrowinning for 10 h,the Sn^(4+)mass concentration in anode cell is 58.6 g/L which can be reused as the tin stipping solution,and the tin purity on the cathode is 99.9%which can be used to prepare PCB.The tin can be recycled.