Cr(VI) transport via a supported ionic liquid membrane containing CYPHOS IL101 as carrier: System analysis and optimization through experimental design strategies
Por:
Miguel, ERD, Vital, X, de Gyves, J
Publicada:
30 may 2014
Resumen:
Chromium(VI) transport through a supported liquid membrane (SLM) system
containing the commercial ionic liquid CYPHOS IL101 as carrier was
studied. A reducing stripping phase was used as a mean to increase
recovery and to simultaneously transform Cr(VI) into a less toxic
residue for disposal or reuse. General functions which describe the
time-depending evolution of the metal fractions in the cell compartments
were defined and used in data evaluation. An experimental design
strategy, using factorial and central-composite design matrices, was
applied to assess the influence of the extractant, NaOH and citrate
concentrations in the different phases, while a desirability function
scheme allowed the synchronized optimization of depletion and recovery
of the analyte. The mechanism for chromium permeation was analyzed and
discussed to contribute to the understanding of the transfer process.
The influence of metal concentration was evaluated as well. The presence
of different interfering ions (Ca2+, Al3+, NO3-, SO42-, and Cl-) at
several Cr(VI): interfering ion ratios was studied through the use of a
Plackett and Burman experimental design matrix. Under optimized
conditions 90% of recovery was obtained from a feed solution containing
7 mg L-1 of Cr(VI) in 0.01 mol dm(-3) HCl medium after 5 h of
pertraction. (C) 2014 Elsevier B.V. All rights reserved.
Filiaciones:
Miguel, ERD:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Quim Analit, Mexico City 04510, DF, Mexico
Vital, X:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Quim Analit, Mexico City 04510, DF, Mexico
de Gyves, J:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Quim Analit, Mexico City 04510, DF, Mexico
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