To provide a process for producing low α ray lead having α ray quantity of 0.1cph/cm2 or below.
An a ray quantify by 210Po collapse in lead concentrate is measured and the lead concentrate of which the α ray quantity by the 210Po collapse is smaller than a reference value 380(dpm/1kg lead content) is selected. The lead concentrate of which the α ray quantity is smaller than the reference value 380(dpm/1kg lead content) is heated and melted together with an alkaline metal salt and a reducing agent in a nonoxidative atmosphere to cause the reduction decomposition of the alkaline metal salt, by which the desulfurization reduction of the lead concentrate is executed and the lead is produced. The resulted lead is used as anode and is subjected to electrolytic refining by using an electrolyte contg. aulfamic acid.
MORI AKIRA
KINOSHITA MAKOTO
OOMURA TOSHIMASA
MOCHIDA HIROMI
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