Marwa Mohamed Faisle
M.Sc. Chemistry
Wastewater discharge from agricultural, domestic or industrial source with a negative effect on the water, health, and the environment. The disposal of untreated wastewater into water stream cause much pollution. Due to the fast growing of the global population and the elaboration of living standard there are demands continuously driving. However, in present wastewater treatment technologies are reaching their end for achieving appropriate water quality to attain human and environmental requirements. Nanotechnology based treatment has offered very efficient and ecofriendly access. The benefits of nanotechnology in wastewater treatment technology focused in specific areas: sensing and detection, pollution control and treatment, this achieving through nano-filtration technique, adsorption of pollutants on nano-adsorbents and the contaminants breakdown by nano-catalyst.
Rapid increase an interest in the use of nano-materials, well developed internal pore structures of nano-particles and their tendency to functionalize with various chemical surface groups increase their affinity towards target contaminants. Recent studies suggest that many of the recent wastewater problems could be solved using nanomaterials.
Nano particles have great interacting, absorbing and reacting abilities due to their very small size and elevated proportion of atoms at their surface, they can achieve energy conservation due to their small size which may lead in the end to cost saving. The unique properties of Carbon Nano Tubes CNTs have attracted the attention of many researchers, their high strength, and resistance to acidic and basic media, high surface area good thermal, electrical, and conductive properties brought up the possibility of a novel structure with extra -ordinary properties. The CNTs consist of very thin honeycomb structures of graphene sheets rolled up in cylindrical shape with a few nanometer diameter and many micron or even centimeters length as shown in figure, including single walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) distinguished by the layers numbers. Due to the hexagonal network of carbon atoms and strong van der Waals interaction forces between the nanotubes, they form tight bundles as show in figure (1).
Figure (1): Schematic diagram of graphene sheet layers of CNTs.
The CNTs have presented excellent adsorption efficiencies for various organic pollutants, heavy metals, i.e. lead, cadmium, Application of CNTs in wastewater treatment is not restricted to adsorption and filtration; CNTs have strong antimicrobial properties that control microbial pathogens. They are not strong oxidants and relatively inert in water resulting in avoiding the formation of carcogenic disinfection byproducts (DBPs)
The effect of metal and metal oxide nano particles, such as nano silver, nano copper ,nano gold, titanium dioxide , aluminum oxide, silicon dioxide and zinc oxide on wastewater treatment plants (WWTPs) have been widely investigated. However, few studies have investigated the effect of CNTs on WWTPs.
[References]
- M. Faisle, (2017):” Preparation of nanomaterials and its application for wastewater chemical and biological treatment. “M. Sc. Thesis, Chemistry Department, Science faculty, Fayoum University, Egypt.