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21 Nanomaterials and Biopolymers for the Remediation of Polluted Sites

that has been altered by the loosening of the earth, humus formation, chemi-

cal decomposition, and by the transportation of humidification and chemical

decomposition products” [3]. The modern agricultural practices are heavily depen-

dent on the application of chemical pesticides, inorganic fertilizers, and growth

regulators which has not only raised the agriculture production but has also

resulted in depletion of natural resource, environmental deterioration, and loss of

crop diversity [4]. Owing to their exceptional ability to efficiently adsorb as well

as high surface area, biopolymeric nanocomposites are considered as an excellent

support materials of metallic photocatalysis for the removal of contaminants from

the polluted sites. The present chapter envisages about application of various

nanomaterials such as metal/metal oxides and biopolymeric nanocomposites for

effective remediation of water and soil.

21.2

Water Remediation

21.2.1

Application of Nanotechnology for Water Disinfection

and Textile Dye Degradation

The availability of potable water is a serious problem in rural areas of developing

countries. The economic, social, and environmental impacts of poor water supply

and sanitation have posed a lot of implications on the health and safety of the peo-

ple, especially children, elderly, and poor closely associated with the accessibility of

adequate, safe, and affordable water supplies. Hence, there is an increasing demand

for providing potable water to people in both the developed and developing coun-

tries which can be addressed by the development of innovative new technologies

and materials [5].

The textile industry represents a major threat to the environment due to release of

dye effluents into the surrounding water bodies due to consumption of large quan-

tities of water at their different steps of dyeing and finishing process. Due to the

presence of —N=N— bond, synthetic textile dyes often become recalcitrant and

carcinogenic in nature. These synthetic dyes also consists of complex aromatic struc-

tures which cannot be easily degraded. Most of the synthetic dyes have been inten-

tionally designed to resist aerobic microbial degradation and are converted to toxic

or carcinogenic compounds [6].

The traditional techniques deployed for the removal of dyestuff are the application

of biological, adsorption, and coagulation. Each of the method has its own advan-

tages as well as bottlenecks.

In recent years, emergence of nanotechnology has been the subject of extensive

research and can provide us ways to purify air, water, and soil using engineered

nanoparticles as catalysts. Nanotechnology is defined as the “deliberate manipula-

tion of matter at a scale of 1–100 nm.” This process involving deliberate manipu-

lation of matter size scales of less than 100 nm offers the possibility of an efficient

removal of pollutants, mutagens, and microorganisms pertaining to the area of water

purification, air purification, and soil remediation. Furthermore, the utilization of