Center for Environment and Energy Research and Studies (CEERS)
Abstract
A new organic–inorganic composite cation exchanger polyaniline
Sn(IV) silicate has been synthesized. The physicochemical properties of
this ion exchanger were determined using different analytical
techniques including fourier transform infrared spectroscopy,
simultaneous thermogravimetry–differential thermogravimetry
analyses, X-ray diffraction, scanning electron microscopy,
energy-dispersive X-ray spectroscopy and elemental analysis studies.
Ion exchange capacity and effect of heating temperature on ion exchange
capacity were also carried out on this ion exchange material.
Adsorption properties for different metal ions have been investigated
and the results revealed that polyaniline Sn(IV) silicate had the
highest adsorption capacity for Cd2+ ion. It’s selectivity was
tested by achieving some important binary separations. Dependence of
adsorption on contact time, temperature, pH of the solution and
exchanger dose had been studied to achieve the optimum conditions.
Adsorption kinetic study showed that the adsorption process followed
the first order kinetics. Adsorption data were fitted to linearly
transformed Langmuir isotherm with R2 (correlation coefficient)
>0.99. The maximum removal of Cd2+ was found at pH 9. The adsorption
was fast and the equilibrium established within 40 min. Thermodynamic
parameters viz- entropy change, enthalpy change and Gibb’s free
energy change were also calculated
