In this study, crushed metal enrichment (CME) originated from waste printed circuit boards was treated by a novel oxidizing alkali-salt fusion process to separate and recover metal values. The fusion system consists of CME, alkaline medium and oxidant. Based on former studies, mixture of NaOH and Na2CO3 was selected as alkaline medium, while NaNO3 as the oxidant. Parameters and factors of the fusion process were studied systematically, and the optimized conditions were determined as CME/Na2CO3/NaOH/NaNO3 mass ratio of 1:1:3:3, fusion temperature of 600°C, and fusion time of 40 min. Under these conditions, 84.55% of Sn, 73.97% of Pb, 95.22% of Al and 78.87% of Zn were transferred into solution, while over 99.51% of Cu and all precious metals were enriched in the residue.
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