Page 664 - Polymer-based Nanocomposites for Energy and Environmental Applications

610 Polymer-based Nanocomposites for Energy and Environmental Applications

engineering applicability, and technical feasibility, this material is strongly rec-
ommended for removal of metal ions from industrial effluents and wastewater. Syn-
thetic procedures of polyaniline-based nanocomposites are simple and economical,
which not only can be used at large industrial scale due to low cost but also improve
the profitability. Indeed, polyaniline-based material adsorbents and ion exchangers
offer a lot of encouraging benefits for commercial purposes in the future.
The potential and efficient applications of polyaniline-based sorbent must be
examined by enhancing their sorption capacity, reusability, and life span for the
removal of environmental pollutants. However, very less study has been carried
out in this area especially to understand the adsorption and ion-exchange mechanism.
We hypothesize the possibility of metal ions removal on polyaniline-based material
through chelation, ion-exchange mechanism, and electrostatic interaction mechanism.
The chelating sites present on the materials donate electron pair to metals and form the
metal chelates, whereas ion-exchange sites on the surface of adsorbents are converted
to cationic form and cations are exchanged with metal ions, being a cationic ion, in the
equilibrating solution. They can perform as more effective sorbents than other adsor-
bents in terms of high sorption capacity, selectivity, faster kinetics, and high regen-
eration capacity. Polyaniline nanocomposites fabricated with various metal oxides
are very useful and efficient for the removal of metal ions from environmental and
biological samples. The extraordinary characteristics of polyaniline nanocomposites
make them promising materials for applications in remediation of environmental pol-
lutants. Despite some complications, nanocomposites are important materials for the
future.

Acknowledgment

One of the authors (Dr. Akil Ahmad) is thankful to the “National Research Foundation (Grant
No. UID: 99623)” and “University of KwaZulu- Natal, South Africa,” for providing the finan-
cial assistance.

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