In this study, the ability of modified silica aerogel with mercapto
functional group (-HS) to remove Cu(II) and Hg(II) ions from water
was investigated by batch technique. Three silica aerogels modified in
different extent were prepared by incorporation of different amounts
of MPME in standard sol–gel synthesis and then dried by supercritical
CO2. From the measuring of physical properties, it can be seen that
these aerogels are thermally stable until temperature of 300 °C,
specific surface area is lowered when higher amount of precursor
MPME is incorporated and the morphology is not affected much
compared to unmodified silica aerogel. From the measurements, it
was found out that, for the removal Cu(II) ions, MPME1 aerogel
sample is the most appropriate, with the least incorporation of MPME
because it still has very large specific surface area. Optimal conditions
of adsorption on these aerogels were then determined. Cu(II) removal
was the most efficient at pH 4 and Hg(II) removal was efficiently
performed at the initial pH 6. The equilibrium time for both heavy
metal ions was reached within 2 h. The equilibrium isotherm data
were fitted well by Freundlich and Langmuir isotherm model as
evidenced from the good agreement between the experimental and
calculated values. The results of the present investigation illustrate
that modified silica aerogel with mercapto functional groups could be
used as an adsorbent for the effective removal of Cu(II) and Hg(II) ions
from aqueous solutions. Further work should be carried out to
optimize the system from the regeneration point of view and also to
better characterize the adsorption behavior of the adsorbent with
respect to column operation.
In this study, the ability of modified silica aerogel with mercaptofunctional group (-HS) to remove Cu(II) and Hg(II) ions from waterwas investigated by batch technique. Three silica aerogels modified indifferent extent were prepared by incorporation of different amountsof MPME in standard sol–gel synthesis and then dried by supercriticalCO2. From the measuring of physical properties, it can be seen thatthese aerogels are thermally stable until temperature of 300 °C,specific surface area is lowered when higher amount of precursorMPME is incorporated and the morphology is not affected muchcompared to unmodified silica aerogel. From the measurements, itwas found out that, for the removal Cu(II) ions, MPME1 aerogelsample is the most appropriate, with the least incorporation of MPMEbecause it still has very large specific surface area. Optimal conditionsof adsorption on these aerogels were then determined. Cu(II) removalwas the most efficient at pH 4 and Hg(II) removal was efficientlyperformed at the initial pH 6. The equilibrium time for both heavymetal ions was reached within 2 h. The equilibrium isotherm datawere fitted well by Freundlich and Langmuir isotherm model asevidenced from the good agreement between the experimental andcalculated values. The results of the present investigation illustratethat modified silica aerogel with mercapto functional groups could beused as an adsorbent for the effective removal of Cu(II) and Hg(II) ionsfrom aqueous solutions. Further work should be carried out to optimize the system from the regeneration point of view and also tobetter characterize the adsorption behavior of the adsorbent withrespect to column operation.
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