Friday, May 29, 2009

Kentucky environmental attorney Sanders says Rice University to field test nanorust to remove arsenic from drinking water supply in Guanajuato, Mexico

Rice University’s Center for Biological and Environmental Nanotechnology (CBEN) have announced a pilot test for a revolutionary, low-cost way to remove arsenic from drinking water. CBEN's arsenic-removing technology is based "nanorust," which are tiny bits of iron oxide smaller than living cells.

Raw water for the city of Guanajuato contains arsenic. As a result, CBEN scientists have signed an agreement with the University of Guanajuato and the Municipal Water and Sewerage Authority of Guanajuato (Simapag) for a pilot test the use of nanotechnology to clean contaminated water in Guanajuato, Mexico.

The agreement is the first known test of nanoparticles for water treatment in a municipal water treatment plant.

Arsenic chemically binds to nanorust because arsenic has a high affinity toward iron oxides. Laboratory tests have demonstrated that nanorust is very effective at removing arsenic from water. Nanorust are nano-scale magnetite particles. Magnetite (Fe3O4) is an iron oxide, much like rust, so the term “nanorust” was coined for magnetite nano-particles.

Whereas rust (FeO) only contains iron in +2 oxidation states, Fe3O4 has iron in both +2 and +3 states. Nanorust crystals are so tiny that they are measured in the scale of nanometers. They are also highly effective in attracting arsenic particles dissolved in water.

Because of its ability to bind to arsenic, nanorust may be a low-cost means of removing arsenic from drinking water supplies. CBEN plans to test nanorust-coated sand in sand filters to treat groundwater from wells. If all goes as planned, the arsenic in the raw water will be captured by the nanorust-coated sand in the filters. For the time being, water treated with nanorust will not be released for human consumption.

Arsenic is a colorless, odorless, tasteless element, and prolonged exposure to dangerous levels of arsenic can lead to skin discoloration, sickness and cancer. Arsenic-poisoned drinking water is a global problem, affecting tens of millions of people in communities in Asia, Africa, North America, South America and Europe.