Abstract: Provided is a method for manufacturing high purity tin including: depositing electrodeposited tin on the surface of a cathode by electrowinning in an electrolytic bath in which a diaphragm is placed between an anode and the cathode, by using a raw material for tin as the anode and a leachate obtained by electrolytically leaching the raw material for tin in a sulfuric acid solution as an electrolytic solution, the electrolytic solution containing a smoothing agent for improving a surface property of the electrodeposited tin; discharging the electrolytic solution from the electrolytic bath such that lead in the discharged electrolytic solution is removed; and putting the electrolytic solution from which lead is removed back into the electrolytic bath.

Abstract: High purity tin and tin alloy are provided in which the respective contents of U and Th are 5 ppb or less, the respective contents of Pb and Bi are 1 ppm or less, and the purity is 5N or higher, provided that this excludes the gas components of O, C, N, H, S and P. A cast ingot of the tin or alloy has an ? ray count of 0.001 cph/cm2 or less. Since recent semiconductor devices are densified and of large capacity, there is risk of a soft error occurring due to ? ray from materials in the vicinity of the semiconductor chip. Thus, there are demands for purifying soldering material used in the vicinity of semiconductor devices, and materials with fewer ? rays. The disclosed tin, alloy, and method reduce ? dose of tin so as to be adaptable as the foregoing material.

Abstract: The invention provides a dry electroblotting system for dry blotting gels, in which the system includes an electroblotting transfer stack that comprises an analysis gel and a blotting membrane, an anode, a body of anodic gel matrix juxtaposed with the anode between the anode and the transfer stack, a cathode, and a body of cathodic gel matrix juxtaposed with the cathode between the cathode and the transfer stack, in which the anodic gel matrix and the cathodic gel matrix each comprise an ion source for electrophoretic transfer. The dry electroblotting system does not use any liquid buffers that are added to the system just before electroblotting (such as when the transfer stack is being assembled). The anode, the cathode, or both can be separate from a power supply and provided as part of a disposable electrode assembly that also includes a body of gel matrix that includes ions for electrophoretic transfer.

Abstract: A method for selective dissolution of tin and/or lead- or tin-containing alloys from printed circuit boards is provided comprising contacting a printed circuit board with a solution comprising Ti(IV) and an acid which forms stable and soluble salt of Ti(III), Ti(IV), Sn(II) and Pb(II), under conditions to effect dissolution of substantially all of the Sn and/or Pb- or Sn-containing alloy therefrom, as Sn(II) and/or Pb(II) and recovering from the solution by electrolytic reduction substantially all of the Sn(II) and/or PB(II) species as Sn and/or Pb. After the electrolytic reduction step, the oxidant metal species is regenerated by oxidation and recycled to the first stage of the process.

Abstract: The present invention provides methods and compositions for use in recovery of metal from waste solutions minimally comprising tin as a dispersed insoluble oxide and iron as ferric ion. In general, the invention involves increasing the pH of the waste solution using a strong alkali to solubilize the tin, and adding a complexing agent(s) for other metal ionsin the solution, e.g., ferric ion, and/or cupric ion, and/or plumbous ion, so as to maintain the iron and other metal ions in a soluble state in the treated waste solution. The treated waste solution can then be used in an electroplating system to recover the tin and other metals. The electroplated, treated waste solution that is produced after tin recovery is environmentally safe, and, after pH adjustment, can generally be disposed of in most sanitary sewage systems.

Abstract: The present invention concerns a process for the electrolytic extraction of the tin found a quantity of less than 1 g/l and in a chelated form in organic solutions.The process consists of using an electrolysis unit comprising an anode compartment and cathode compartment separated by a physical barrier, introducing the organic solution into the cathode compartment and carrying out the electrolysis in galvanostatic or potentiostatic mode.This process can be applied to the recycling of photographic effluents containing tin, in particular to the processing of reversal products.