The phosphine oxides Cyanex 921 and Cyanex 923 as carriers for facilitated transport of chromium (VI)-chloride aqueous solutions

The behaviour of the phosphine oxides Cyanex 921 and Cyanex 923 in the facilitated transport of chromium (VI) from chloride solutions is described. Transport is studied as a function of several variables such as stirring speeds of the aqueous phases, membrane phase diluent, hydrochloric acid concent...

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Detalhes bibliográficos
Autores: Alguacil, Francisco José, López-Delgado, Aurora, Alonso Gámez, Manuel, Sastre Requena, Ana María
Formato: artículo
Fecha de publicación:2004
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/36578
Acesso em linha:http://hdl.handle.net/10261/36578
Access Level:acceso abierto
Palavra-chave:Facilitated transport
Cyanex 921
Cyanex 923
Chromium (VI)
Descrição
Resumo:The behaviour of the phosphine oxides Cyanex 921 and Cyanex 923 in the facilitated transport of chromium (VI) from chloride solutions is described. Transport is studied as a function of several variables such as stirring speeds of the aqueous phases, membrane phase diluent, hydrochloric acid concentration in the source phase and chromium and carrier concentrations. The separation of chromium (VI) from other metals presented in the source phase as well as the behaviour of phosphine oxides with respect to other neutral organophosphorous derivatives (tri-n-butylphosphate (TBP) and dibutyl butylphosphonate (DBBP)) are also investigated. Moreover, by using hydrazine sulphate in the receiving phase, Cr(VI) is immediately reduced to the less toxic Cr(III).