Environmental Engineering Reference
In-Depth Information
(a)
(b)
(c)
20 nm
200 nm
200 nm
200 nm
FIGURE 23.6
TEM images of PVA-Ag nanoiber (a), PVA/dextran-Ag nanoiber (b), and PVA/methylcellulose-Ag nanoiber (c).
(From Mahanta, N., Valiyaveettil, S.
RSC Adv.
, 2, 11389, 2012.)
(a)
(b)
Ag/TiO
2
nanofiber
Water
Filtration
Disinfection
Degradation
Glass fiber
FIGURE 23.7
(See color insert.)
(a) Schematic representation of a hypothesis of a Ag/TiO
2
nanoiber membrane; (b) photo-
graph of Ag/TiO
2
nanoiber membrane. (From Liu, L. et al.,
Water Res.
, 46, 1101, 2012.)
single-membrane system. Polyol synthesis was used for the deposition of Ag NPs on
electrospun TiO
2
nanoibers (Figure 23.7). The permeate lux of the Ag/TiO
2
nanoiber
membrane was remarkably high compared to a commercial P25 deposited membrane.
The Ag/TiO
2
nanoiber membrane achieved 99.9% bacterial inactivation (
E. coli
) and
80.0% dye degradation under solar irradiation within 30 min.
45
Although many research articles have been published on the antimicrobial activities of
Ag-incorporated nanoibers, no signiicant progress has been made in testing the iltration
performance and disinfectant eficiency in a low-through system. A major leap toward
this direction might replace existing conventional disinfection techniques such as chlori-
nation and UV-assisted disinfection.
23.3.2 Removal of Organic Compounds
All the pesticides, oils, and even proteins belong to the class of organic compounds. These
contaminants enter the water stream through soil erosion, surface runoff, or through
leaching. Substantial research has been carried out to eliminate these organic compounds
