In the process of purification of water, nanotechnology provides the
possibility of an effective removal of pollutants and germs. In recent times,
nanoparticles (NPs), nanopowder and nanomembranes have been used for the detection
and removal of chemical and biological substances that contain metals like cadmium,
copper, lead, mercury, nickel, zinc, etc., nutrients like phosphate, ammonia, nitrate and
nitrite, algae, cyanobacterial toxins, viruses, bacteria, parasites, and antibiotics.
Commonly, four classes of nanoscale materials that are being evaluated as functional
materials for water purification are metal-containing nanoparticles, carbonaceous
nanomaterials, dendrimers and zeolites. Carbon nanotubes and nanofibers are also used
in the techniques of water purification. Nanomaterials (NMs) give the best results in
water treatment in comparison to other techniques because NMs have a high surface
area (surface/volume ratio). Silver NPs affect the activated sludge of microorganisms
and play an important role in wastewater treatment since they restrain their activity and
significantly reduce their number. Carbon nanostructures are widely used as
nanoadsorbents for wastewater treatment owing to their abundant availability, costeffectiveness, high chemical and thermal stabilities, high active surface areas, excellent
adsorption capacities, and environmentally friendly nature. Due to the high utility of
nanotechnology in the treatment of pollutants, this chapter further highlights various
fundamental aspects of nanotechnology, such as types, synthesis, applications and
future directions for a green and sustainable environment.
Keywords: Activated carbon, Carbon nanotubes, Dendrites, Graphene, Green synthesis, Nanoparticle, Membrane filtration, Nanofiber, Nano silver, Nanocomposites, Photocatalytic, Zeolite.