In developed countries, nanotechnology is being promoted as a technological revolution that will help to solve an array of problems. It promises to provide new ways of solving some of developing countries' chronic challenges such as treating tuberculosis and malaria, preserving food, and diversifying energy sources and other applications. Many nanomaterials are now globally manufactured for structural applications (ceramics, catalysts, films and coatings, and composite metals), skin care products (cosmetics), information and communication technologies (nanowires and optoelectronic materials), biotechnology (drug delivery, diagnostic marks, and biosensors) and environmental technologies (nanofiltration and membranes).
Nanotechnology provides many promising solutions for improving "point of use" water treatment – ie becoming more efficient and effective about removing all the contaminants in water to make it safe to drink. There are three nanotechnologies for water treatment; nano-filters with membrane (carbon nanotubes) to filter out contaminants, nanosensors to detect contaminants in the water and nanomaterials to help with water pollution remediation, and the desalination.
In the past years, mechanical or chemical methods have been used for effective filtration techniques but the recent technique is nanofiltration. Nanofiltration is a reliably recent membrane filtration process used most often with low total dissolved solids water such as surface water and fresh groundwater, with the purpose of softening (polyvalent cation removal) and removal of disinfecting by-product precursors such as natural organic matter and synthetic organic matter. Using nanoscale particles increases the efficiency to absorb the contaminants and is comparatively inexpensive compared to traditional precipitation and filtration methods because the nano-enabled technologies include a variety of different types of membranes and filters based on carbon nanotubes, nanoporous ceramics, magnetic nanoparticles and other nanomaterials . Its mechanism is based on the use of membranes with suitable hole sizes, where the liquid is pressed through the membrane. Nanoporous membranes are suitable for a mechanical filtration with extremely small pores smaller than 10 nm (nanofiltration) and composed of nanotubes. Magnetic nanoparticles offer an effective and reliable method to remove heavy metal contaminants from waste water by making use of magnetic separation techniques.
Separation membranes with structure at the nanoscale can also be used in low cost methods to produce potable water. In a recent study in one of the developing countries, tests were run using polymeric nanofiltration in conjunction with a reverse osmosis process to treat brackish groundwater (water that is salty, but less so than sea water). These tests produced potable water. The reverse osmosis membranes removed a large majority (about 99%) of all the solutes, but the concentrations of essential nutrients, such as calcium and magnesium ions, were reduced to levels that were below the specifications of the World Health Organization standard for drinking water . The product water there before had to be spiked with these nutrients to provide drinking water of the required quality.
Low-cost nanostructured separation membranes methods have shown to be effective in producing potable water. Providing nanofiltration methods to developing countries, to increase their supply of clean water, is a very inexpensive method compared to conventional treatment systems.