Researchers at the DOE's Pacific Northwest National Laboratory have developed a material that removes mercury and other toxic substances from coal-burning, power plant wastewater.
It's estimated that coal-burning power plants contribute about 48 tons of mercury to the U.S. environment annually.
The synthetic material features a nanoporous ceramic substrate with a specifically tailored pore size and a high surface area. One teaspoon's worth of this substance has a surface area equaling that of a football field. "This substance has proven to be an effective and voracious tool for absorbing mercury," says Shas Mattigod, lead chemist and project manager.
Self-assembled monolayers on mesoporous support (Samms) technology integrates a nanoporous silica-based substrate with a new method for attaching monolayers, or single layers of densely packed molecules designed to attract mercury or other toxic substances. Initial testing shows after three treatments, 99.9% of mercury in simulated wastewater was captured, reducing levels from 145.8 ppm to 0.04. The waste passes EPA requirements for land or sewer disposal.
"We expect this technology will bring huge savings to users faced with costly disposal of mercury in the waste stream," adds Mattigod. Samms technology can also be adapted to target other toxins such as lead, chromium, and radionuclides.