The extensive
use of chromium in leather tanning, metallurgy, electroplating and other
industries has resulted in the release of aqueous chromium to the subsurface at
numerous sites. Cr (VI) has received considerable attention owing to its
extensive industrial applications and has long been recognised as a toxic
substance due to its strong oxidising
potential and the ease with which it can cross the biological membranes.
In recent years the application of various solvent extraction technologies to
the removal and concentration of chromium have been widely studied; chemical
precipitation, ion exchange, reverse osmosis, diffusion dialysis, adsorption,
liquid membrane technique are some of the alternatives that have been reported
in the literature. Recently supported
liquid membrane (SLM) extraction is an alternative to conventional solvent extraction due to
its advantages like high selectivity, operational simplicity, low solvent
inventory, low energy consumption, zero effluent discharge
and combination of extraction and
stripping into one single unit. In this work
the selective separation of chromium from acidic media, containing the
mixtures of chromium and nickel by SLM
was investigated using TOA (tri-octylamine) as carrier. The liquid membrane was
consisted of the desired concentration of an extractant (TOA), a modifier (TBP), and a
diluent (chloroform, kerosene, cyclohexane). The membrane support was
microporous hydrophobic polypropylene
Celgard 2500. Such parameters as, the solvent type, feed solution pH,
extractant (TOA) concentration, modifier (TBP) concentration and temperature
were experimentally studied and the optimum conditions were determined. The
permeation coefficients (P) and the initial fluxes of chromium (Jo) were
calculated. Separation factors of
chromium over nickel
was calculated from the
experimental measurements.
Primary Language | English |
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Subjects | Engineering |
Journal Section | Research Article |
Authors | |
Publication Date | June 18, 2019 |
Published in Issue | Year 2019 Volume: 7 Issue: 1 |
Manas Journal of Engineering