Application of hydrophobic extractant in aqueous two-phase systems for selective extraction of cobalt, nickel and cadmium

• Autor(a) principal: Rodrigues, Guilherme Dias
• Data de Publicação: 2013
• Outros Autores: Lemos, Leandro Rodrigues de, Silva, Luis Henrique Mendes da, Silva, Maria C. Hespanhol da
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1016/j.chroma.2013.01.003; http://www.locus.ufv.br/handle/123456789/19402
• topic: Cobalt; Nickel; Cadmium; Aqueous two-phase system; Hydrophobic extractant

This work developed a new and efficient method of extracting and separating Co(II), Ni(II) and Cd(II) in aqueous two-phase systems (ATPS) composed of triblock copolymer (L64) + Na2C4H4O6 + water and L64 + Li2SO4 + water using the hydrophobic extractant 1-nitroso-2-naphtol, which complexes the metal ions and partitions in the triblock copolymer micelles in the ATPS top phase. Metal extraction from the salt-rich phase to the copolymer – rich phase is strongly affected by the fine-tuning of the following parameters: amount of added extractant, type of electrolyte, pH, and tie-line length. Excellent separation factors (Si,j) between the metals were obtained at pH = 3.00 (SCo,Cd = 1550 and SNi,Cd = 16,700) and pH = 1.00 (SCo,Ni = 826). In the interference study, Co(II) was selectivity extracted in the top phase in the presence of Ni(II) and Cd(II) in a concentration of up to 20 times the cobalt level in the system.