Water Pollution and Nanotechnology

Nanotechnology is being used to develop solutions to three very different problems in water quality.

One challenge is the removal of industrial water pollution, such as a cleaning solvent called TCE, from ground water. Nanoparticles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. Studies have shown that this method can be used successfully to reach contaminates dispersed in underground ponds and at much lower cost than methods which require pumping the water out of the ground for treatment.

Another challenge is the removal of salt or metals from water. A deionization method using electrodes composed of nano-sized fibers shows promise for reducing the cost and energy requirements of turning salt water into drinking water.

The third problem concerns the fact that standard filters do not work on virus cells. A filter only a few nanometers in diameter is currently being developed that should be capable of removing virus cells from water.

 

See the following for more about the potential of nanotechnology in removing contaminates from water.

 

Nanotechnology Applications in Water Pollution

 

1. Combining a nanomembrane with solar power to reduce the cost of desalinating seawater

2. Using iron nanoparticles to clean up carbon tetrachloride pollution in ground water

3. Using silver chloride nanowires as a photocatalysis to decompose organic molecules in polluted water.

4. Using an electrified filter composed of silver nanowires, carbon nanotubes and cotton to kill bacteria in water.

5. Nanoparticles that can absorb radioactive particles polluting ground-water

6. Coating iron nanoparticles allow them to neutralize dense, hydrophobic solvents polluting ground-water

7. Using nanowire mats to absorb oil spills

8. Using iron oxide nanoparticles to clean arsenic from water wells.

9. Using gold tipped carbon nanotubes to trap oil drops polluting water.

10. Using antimicrobial nanofibers and activated carbon in a disposable filter as an inexpensive way to clean contaminated water.

11. Researchers at Pacific Northwestern Laboratory have developed a material to remove mercury from groundwater. The material is called SAMMS, which is short for Self-Assembled Monolayers on Mesoporous Supports. This translates taking a ceramic particle whose surface has many nano-size pores and lining the nanopores with molecules that have sulfur atoms on one end, leaving a hole in the center that is lined with sulfur atoms as shown in figure-SAMMS. They line the nanopores with molecules containing sulfur because it bonds to mercury, so mercury atoms bond to the sulfur and are trapped in the nanopores.