Sustainable technologies for the regeneration of acidic tin stripping solutions used in PCB fabrication

被引:9
作者
Kerr, Charlie [1 ]
机构
[1] Tin Technology Ltd, St Albans, Herts
关键词
Diffusion; Manufacturing industries; Printed-circuit boards; Sustainable development;
D O I
10.1108/03056120410520623
中图分类号
学科分类号
摘要
Electroplated tin deposits are used as etch resists during the processing of printed circuit boards. The tin coating protects the copper tracks during etching but is subsequently removed (stripped) to expose the defined copper circuitry. The commonly used stripping solutions are based on nitric acid and after use they represent a very acidic waste product with a high metal content. The disposal of these spent strippers is typically via off-site neutralisation and precipitation followed by subsequent landfill. This is clearly a non-sustainable waste of valuable resources and a practice that is increasingly undesirable as environmental legislation becomes more stringent. This paper outlines the results of a scoping study carried out into current industry practices for tin stripping and details of components of a potential integrated treatment system for these stripping solutions. Individual technologies for such an integrated system incorporate the recovery of the tin oxide by filtration, the concentration and reuse of nitric acid solutions by diffusion dialysis and the reclamation of other metals, i.e. copper by electrowinning. © 2004, Emerald Group Publishing Limited
引用
收藏
页码:51 / 58
页数:7
相关论文
共 9 条
[1]  
Ahn J.W., Ahn J.G., Lee M.S., Recovery of nitric acid and valuable metals from spent nitric etching solutions of PCB, Taehan Kumsok, 40, 1, pp. 116-121, (2002)
[2]  
Integrated Pollution Prevention and Control: A Practical Guide, 2nd ed., (2002)
[3]  
Hazardous Waste Management Market Pressures and Opportunities, Background Paper, Bristol., (2003)
[4]  
Erikison P.K., Lien L.A., Membrane Technology for Treatment of Wastes Containing Dissolved Metals, (1996)
[5]  
Geraghty K., Goosey M.T., Smith K., Investigation of the Technical and Economic Viability of Recycling 25-litre Plastic Drums Used to Supply Process Chemistry to the Metal Finishing Industries, (2003)
[6]  
Minhan D., Evaluation of two cross-flow ultra-filtration membranes for isolating organic colloids, Marine Chemistry, 62, pp. 117-136, (1998)
[7]  
Moleux P.G., A case study and update using diffusion dialysis to purify acid in a plant that fabricates PCBs, Proceedings, 89th Annual Meeting -- Air and Waste Management Association, (1996)
[8]  
Reclamation of Nitric Acid from Solder Strip, (1995)
[9]  
Scott K., Chen X., Atkinson J.W., Todd M., Armstrong R.D., Electrochemical recycling of tin, lead and copper from stripping solution in the manufacture of circuit boards, Resources, Conservation and Recycling, 20, pp. 43-55, (1997)