258
T. Sahoo et al.
nanosorbent for enhancing the efficiency of removal and other group includes using
it as photocatalyst in order to degrade these contaminants into lesser toxic form.
11.3.3 Titanium Oxides Nanomaterial
Titanium dioxide displays photocatalysis when ultraviolet radiation is present. Titanium dioxide possesses antibacterial property because of the release of reduced
oxygen species like peroxide and hydroxyl free radicals produced in the presence of
ultraviolet radiation via the series of reduction and oxidation reaction occurring in a
cell. The unique property of using titanium dioxide nanomaterial as disinfectant is
their characteristic of displaying photocatalysis also in the presence of visible sunlight (Sakthivel and Kisch 2003). This nature can be upgraded by mixing titanium
dioxide with different metals. It is a very efficient and perfect option for the treatment of water due to its stability in water, cost-effectiveness and non-toxicity while
ingestion. It is used as thin-film coating on the surface of reactor and in UV reactor
as slurry (Reddy et al. 2015).
11.4 Zinc Oxide Nanoparticles
Like titanium dioxide, zinc oxide nanoparticles demonstrate better ultraviolet absorption and also efficient photocatalysis. During photocatalysis, zinc oxide nanomaterial
produces hydrogen peroxide in the cells as a result of which cell components are
subjected to oxidation. Moreover, they are also capable of inhibiting the growth of
bacteria by penetrating into the envelope of the cell, thereby disorganizing the membrane of bacteria. But, if zinc oxide nanomaterials enter the natural water sources,
they can be dangerous for the aquatic organisms. These materials get dissolved easily,
and this limits its use in drinking water Szabó et al. (2003).
11.4.1 Nanocomposites in Water Treatment
11.4.1.1 Nanocomposite Membrane
The membrane processes which are available commercially for the purification
of water are ultrafiltration, nanofiltration, microfiltration, reverse osmosis, electrodeionization and electrodialysis (Frenkel 2008). Few other processes which are used
in limited number include pervaporation, membrane distillation and forward osmosis. The membrane process of nano- and ultrafiltration is found to be efficiently
separating emulsion and oil. But, the ultrafiltration technique fails in the removal
of contaminants of large size because they do not contain any charge. As we know
T. Sahoo et al.
nanosorbent for enhancing the efficiency of removal and other group includes using
it as photocatalyst in order to degrade these contaminants into lesser toxic form.
11.3.3 Titanium Oxides Nanomaterial
Titanium dioxide displays photocatalysis when ultraviolet radiation is present. Titanium dioxide possesses antibacterial property because of the release of reduced
oxygen species like peroxide and hydroxyl free radicals produced in the presence of
ultraviolet radiation via the series of reduction and oxidation reaction occurring in a
cell. The unique property of using titanium dioxide nanomaterial as disinfectant is
their characteristic of displaying photocatalysis also in the presence of visible sunlight (Sakthivel and Kisch 2003). This nature can be upgraded by mixing titanium
dioxide with different metals. It is a very efficient and perfect option for the treatment of water due to its stability in water, cost-effectiveness and non-toxicity while
ingestion. It is used as thin-film coating on the surface of reactor and in UV reactor
as slurry (Reddy et al. 2015).
11.4 Zinc Oxide Nanoparticles
Like titanium dioxide, zinc oxide nanoparticles demonstrate better ultraviolet absorption and also efficient photocatalysis. During photocatalysis, zinc oxide nanomaterial
produces hydrogen peroxide in the cells as a result of which cell components are
subjected to oxidation. Moreover, they are also capable of inhibiting the growth of
bacteria by penetrating into the envelope of the cell, thereby disorganizing the membrane of bacteria. But, if zinc oxide nanomaterials enter the natural water sources,
they can be dangerous for the aquatic organisms. These materials get dissolved easily,
and this limits its use in drinking water Szabó et al. (2003).
11.4.1 Nanocomposites in Water Treatment
11.4.1.1 Nanocomposite Membrane
The membrane processes which are available commercially for the purification
of water are ultrafiltration, nanofiltration, microfiltration, reverse osmosis, electrodeionization and electrodialysis (Frenkel 2008). Few other processes which are used
in limited number include pervaporation, membrane distillation and forward osmosis. The membrane process of nano- and ultrafiltration is found to be efficiently
separating emulsion and oil. But, the ultrafiltration technique fails in the removal
of contaminants of large size because they do not contain any charge. As we know