Abstract: A coating for mitigating metal whiskers on a metal surface includes a polymeric coating material; and a metal ion complexing agent impregnated within the polymeric coating material, the metal ion complexing agent having a standard reduction potential (E°) that is greater than a metal in the metal surface.

Abstract: The present invention relates to a method of recovering tin and nickel compounds with high purity at a high yield from scrap steel balls for barrel plating through simple processes without using an excess amount of a solvent, the method using an eco-friendly dry pretreatment and subsequent processes including hydrogen reduction and electrolytic refining under certain conditions.

Abstract: Disclosed is tin characterized in that a sample of the tin after melting and casting has an ? dose of less than 0.0005 cph/cm2. Since recent semiconductor devices are highly densified and of high capacity, there is an increasing risk of soft errors caused by the influence of ? rays emitted from materials in the vicinity of semiconductor chips. In particular, there are strong demands for high purification of solder materials and tin for use in the vicinity of semiconductor devices, and demands for materials with lower ? rays. Accordingly, an object of the present invention is to clarify the phenomenon of the generation of ? rays in tin and tin alloys, and to obtain high-purity tin, in which the ? dose has been reduced, suitable for the required materials, as well as a method for producing the same.

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 plant comprises: an electrolysis cell (1″) having a soluble anode (2″1) and an insoluble cathode (3″) without an interposed membrane, means for introducing the bath into the cell and for removing the bath from the cell, means for maintaining an appropriate bath density gradient in the said cell so that, if D1 is the density of the bath in the vicinity of the cathode and if D2 is the density of the bath in the vicinity of the anode, (D2−D1)>100 g/l. Associated process. By virtue of the densitometric separation, the dissolved metal is not redeposited on the cathode and the overall dissolution yield is improved.

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 invention relates to a method and a device for regenerating exhausted tin-plating solutions which contain tin and copper ions, free complexing agent and complexing agent bound to the copper ions, as well as expended and unexpended reducing agent. By means of a suitable rinsing technique, the rinse water of the tin-plating process is concentrated to a 10 to 15 percent dilution of the process solution. The regenerating solution thus produced is fed to an electrolytic cell. The electrolytic cell comprises a cathode chamber, a middle chamber and an anode chamber. The cathode chamber is separated from the middle chamber by an anion-exchange membrane and the anode chamber is separated from the middle chamber by a cation-exchange membrane. The regenerating solution is initially provided in the cathode chamber. Here, the interfering copper component is cathodically deposited.

Abstract: Improved recovery of tin from sludge formed during a halogen-type electrolytic tinplating of steel sheet comprises leaching the sludge with water at a pH of 7 or less, separating an iron-containing sludge remaining after the leaching, alkalifying the filtrate obtained in the first separation step to deposit tin-containing sludge, separating and recovering the tin-containing sludge deposited in the first alkalifying step, redissolving the tin-containing sludge in an alkaline solution, and electrolytic reduction of the alkaline solution. High purity metallic tin is recovered from sludge, at a high yield. Other materials are also recovered for reuse from the filtrate and precipitation, which are formed during the process, without pollution of the operational environment.