Bismuth—Production, properties, and applications
Bismuth, the most metallic element in group V A of the periodic table, is primarily a by-product of lead refining. It is also a by-product of several ore-dressing operations, especially high-grade scheelite and wolframite ores. It is generally recovered by processing lead electrorefining slimes, Kroll-Betterton dross, and other process residues which contain bismuth. No matter the source, it is refined to virgin metal with chlorine. Bismuth’s unique properties make it attractive for a plethora of applications such as alloying additives in steel and aluminum, fusible alloys, and pharmaceuticals. Recent awareness of the “green” nature of bismuth in free-machining steels and similar applications has made it a potential substitute for metals deemed less favorable environmentally.