Environmental protection requires that lead be recycled. The oxidation behavior of recycled lead containing 100-200ppm of impurities was examined using the quartz crystal microbalance technique, and compared to that of virgin lead having 99.99 and 99.9999 mass% purity. Although early-stage oxidation obeyed the cubic rate law for all lead films, the rates of recycled leads far exceeded those of virgin leads in a dry atmosphere at 303K. Both Bi and Cu impurities increased the oxidation rate, but the addition of∼100ppm of Sn affected oxidation behavior only negligibly. XPS and AES revealed that the oxidation product of high-purity Pb film consisted mostly of PbO
2-x. Bi, Cu, and Sn film products were Bi
2O
3, Cu
2O, and SnO respectively. Where the PbO
2-x is an n-conductor, the increased oxidation rate of high-purity Pb film by adding trace amounts of Bi or Cu is interpreted by the controlled valence principle.
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