A synthetic material that can remove mercury and other toxic substances found in wastewater generated by coal-burning power plants has been developed by scientists at the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL), according to a press statement.
This development is especially significant because such facilities annually add about 48 tons of mercury to the environment, and the U.S. Environmental Protection Agency is considering whether to tighten restrictions on mercury releases in effluent from coal-burning power plants, the statement said.
The new material has "a nanoporous ceramic substrate with a specifically tailored pore size [for mercury] and a very high surface area," the statement noted. "The surface area of one teaspoon of this substance is equivalent to that of a football field."
Pore sizes can be varied to accommodate different tasks, and the technology can be "easily adapted to target other toxins such as lead, chromium, and radionuclides," the statement said.
The new material's mercury-absorbing capabilities recently surpassed all expectations in three successive tests, removing 99.9% of the mercury in simulated wastewater (from 145.8 ppm to 0.04 ppm) and enabling it to meet the federal discharge limit of 0.2 ppm for mercury, the PNNL press statement said. In addition, the mercury-laden test solution met Washington state regulations for disposal of dangerous wastes, allowing direct disposal to the sewer system, and federal requirements for land disposal, according to the statement.
For more information, contact PNNL at 888-375-7665 or via e-mail at [email protected].