A Sustainable Methodology to Extract Bismuth from Secondary Sources

Bismuth is a critical metal broadly used in cosmetic, medicine and metallurgy. However, its scarcity in Earth’s crust may impair further applications. An alternative is to recover bismuth from secondary sources. In this work, a methodology to extract bismuth from safety valves of discharged gas cylinders is proposed. Extraction and purification of bismuth were carried out using aqueous two-phase systems (ATPS) prepared with poly(ethylene oxide) polymer or poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) copolymer (L35) and electrolytes (NaNO3, NH4NO3, sodium citrate or Na2SO4)...