M. Paul et al. / Journal of Molecular Catalysis A: Chemical 330 (2010) 49–55
55
which agrees quite well with our previous results on mesoporous
silicotinphosphate material [14]. A relatively higher concentration
of As(III) (∼1000 ppb) similarly show moderate uptake efficiency
(Table 2). For the determination of the Hg removal efficiency ∼200
and 1000 ppb HgCl2 solutions has been taken as stock solutions.
After stirring these solutions with MSTP-Cal sample for 2 h each,
the concentrations of Hg(II) has been analyzed. Under this con-
dition Hg(II) could exist in the solution as a divalent cation [37]
and this could be efficiently adsorbed at the defect P–O− sites. A
considerably high Hg(II) adsorption efficiencies (69.2 and 75.9%)
material. Similarly MSTP-Cal showed good Cd(II) adsorption effi-
ciencies for the respective Cd(II) containing solutions (Table 2).
These As(III/V), Cd(II) and Hg(II) adsorption efficiencies are com-
parable to the mesoporous PMO material LHMS-2 [38] containing
electron donor sites in the pore walls. Due to good adsorption effi-
ciencies for As(III/V) and Hg(II), the MSTP-Cal material can be used
as adsorbent for the removal of toxic metals from contaminated
water.
characterization results revealed the wormhole-like disordered
mesopores in the sample with an average pore dimension of 5.4 nm.
The spectroscopic data suggest that most of the Ti sites present
in this sample are tetrahedrally co-ordinated Ti(IV). Adsorption
activity in liquid phase Friedel–Crafts benzylation of aromatics over
this novel mesoporous material could open up new opportunities
in future.
AB wishes to thank Department of Science and Technology, India
for financial supports. MP and NP are thankful to the CSIR, New
Delhi for their senior research fellowships.
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From our experimental observations we can conclude that
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SDA and an unconventional phosphorous source trimethylphos-
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