Environmental Engineering Reference
In-Depth Information
(a)
(b)
(c)
-
Cl
+
n
m
m
n
N
-
CO
CO
n
OH
O
Cl
+
OH
O
NMe 3
NH 2
FIGURE 12.18
Structures of various polymers used to make bactericidal ilter paper: (a) (polystyrene-block-polyacrylic acid
(PS-b-PAA); (b) polycationic polyacrylamide; (c) poly(isopropanol dimethylammonuim) chloride (PIDMAC).
containing the bacteria is passed by gravity through the ilter paper, the bactericidal agents
are transferred to the bacteria through collisions with the micelles or coated ibers. A syn-
ergy between the biocide and the polyelectrolyte is responsible for the extremely high
eficiency in deactivating the bacteria. This technology represents a very simple approach
to provide potable water under a wide range of primitive conditions.
This chapter summarizes the use of polymeric and organic-inorganic material hybrids
as eficient materials for water disinfection. Unlike inorganic disinfectants, antimicrobial
polymeric materials are advantageous since they do not involve release of harmful by-
products. Development of polymeric-Ag hybrids would be promising owing to the dual
mode of action, wherein the inherent antimicrobial activity of the polymer coupled with
controlled release of silver can confer long-lasting activity. Use of carbonaceous nanomate-
rials can be another viable option for developing effective materials for water disinfection
if the issues such as cost (in case of CNTs) and performance can be taken care of. Most of
the current water disinfection technologies, particularly membrane iltration technology,
suffer from the formation of bioilms that drastically reduce their eficacy. Thus, the ulti-
mate goal is to develop broad-spectrum (bacteria, viruses, protozoan parasites including
the bacterial spores and cysts) antimicrobial water-insoluble polymeric-inorganic com-
posites using antibacterial polymers so that they can be used in membrane iltration tech-
nology wherein the composites can be tailored to inhibit bioilm formation as well.
References
1. UNICEF and WHO. Diarrhoea: Why children are still dying and what can be done, WHO:
Geneva, 2009.
2. World Health Organisation. Guidelines for Drinking Water Quality , vol. 2. WHO: Geneva, 1996.
3. Available at http://www.epa.gov/.
4. S. Baranya, and A. Szepesszentgyörgyi. Flocculation of cellular suspensions by polyelectro-
lytes. Adv. Colloid Interface Sci., 111:117-129, 2004.
5. B. Boltoa, and J. Gregory. Organic polyelectrolytes in water treatment. Water Res., 41:2301-2324,
2007.
6. N. Kawabata, K. Yamazak, T. Otake, I. Oishi, and Y. Minekawa. Removal of pathogenic human
viruses by insoluble pyridinium-type resin. Epidemiol. Infect., 105:633-642, 1990.
7. G. Sun, L. C. Allen, E. P. Luckie, W. B. Wheatley, and S. D. Worley. Disinfection of water by
N -halamine biocidal polymers. Ind. Eng. Chem. Res., 34:4106-4109, 1995.
8. M. W. LeChevallier, and K. K. Au. Water Treatment and Microbial Control: A Review Document .
World Health Organization, Iwa Publishing: London, 2002.
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