For instance, carbon nanotube membranes can remove almost all kinds of water contaminants including turbidity, oil, bacteria, viruses and organic contaminants. Although their pores are significantly smaller carbon nanotubes have shown to have an equal or a faster flow rate as compared to larger pores, possibly because of the smooth interior of the nanotubes. Nanofibrous alumina filters and other nanofiber materials also remove negatively charged contaminants such as viruses, bacteria, and organic and inorganic colloids at a faster rate than conventional filters.
"While the current generation of nanofilters may be relatively simple, it is believed that future generations of nanotechnology-based water treatment devices will capitalize on the properties of new nanoscale materials," the team says.
The researchers point out that several fundamental aspects of nanotechnology have raised concerns among the public and activist groups. They concede that the risks associated with nanomaterials may not be the same as the risks associated with the bulk versions of the same materials because the much greater surface area to volume ratio of nanoparticles can make them more reactive than bulk materials and lead to so far unrecognized and untested interactions with biological surfaces. Water purification based on nanotechnology has not yet led to any human health or environmental problems but the team echoes the sentiment of others that further research into the biological interactions of nanoparticles should be carried out.
|Contact: Alpana Mahapatra|