SnCl4-HCl体系废电路板元器件的分离及锡的回收  

Separation of electronic components from waste printed circuit board and tin recovery in SnCl4-HCl system

作　　者：李陵晨 杨建广 闫万鹏 丁龙 南天翔 陈冰 LI Ling-chen;YANG Jian-guang;YAN Wan-peng;DING-long;NAN Tian-xiang;CHEN Bing(School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院

出　　处：《中国有色金属学报》2019年第7期1543-1550,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51574294)~~

摘　　要：针对现有废旧线路板元器件分离及锡回收工艺所存在环境污染严重、效率低、难以大规模推广应用等问题,采用超声辅助下SnCl4-HCl体系退除元器件管脚处焊锡,达到废线路板元器件分离的目的;同时,采用隔膜电积技术回收退锡液中的锡并再生出SnCl4-HCl退锡剂。结果表明:在反应温度50℃、Sn^4+浓度30g/L、盐酸浓度4.0mol/L、超声频率40kHz、超声功率100W的条件下,反应20min后废线路板元器件管脚及过孔处的焊锡全被退除。以退锡后的液体为电解液,采用隔膜电积技术回收退锡液中的锡;在温度35℃、电流密度200A/m^2、异极距5cm、石墨板为阳极、不锈钢板为阴极的条件下进行隔膜电积8h,阴极得到了平整致密的电积锡,阴极电流效率97.3%,电锡纯度99.9%,阳极电流效率为88.8%,阳极液再生出SnCl4-HCl溶液,可作为退锡液返回用于超声退锡。Addressing the problems of serious environmental pollution,low efficiency,difficult to large-scale application and other issues in the separation of waste circuit board components and tin recycling process,a novel technology using an ultrasonic assisted process based on the SnCl4-HCl system was proposed.The technology adoption diaphragm electrowinning method recovered the tin from the tin stripping solution and regenerated the SnCl4-HCl stripping agent.The results show that,after 20 min at the reaction temperature of 50 ℃,Sn^4+ concentration of 30 g/L,hydrochloric acid concentration of 4.0 mol/L,ultrasonic frequency of 40 kHz and ultrasonic power of 100 W,the waste circuit board components are separated completely.Under the conditions of temperature of 35 ℃,current density of 200 A/m2,heteropolar distance of 5 cm,graphite as anode and stainless-steel as cathode,the diaphragm electrowinning was carried out for 8 h.The cathode obtained flat and compact tin with cathode current efficiency of 97.3% and tin purity of 99.9%.The SnCl4-HCl solution is regenerated from the anode liquid and the anode current efficiency is 88.8%,which can be used as the reaction liquid for ultrasonic stripping tin.

关 键 词：废线路板 元器件分离 锡 再生 隔膜电积技术 

分 类 号：TF814[冶金工程—有色金属冶金] O646.541[理学—物理化学]