MN Impact: Researchers Develop Sponge that Removes Mercury from Water

September 11, 2017

Issue

Despite decades of effort to reduce mercury contamination in water sources low levels of mercury are still being released into the environment causing a threat to public health and harming aquatic life. In northern Minnesota alone, 10 percent of newborns tested positive for mercury concentration above EPA recommendations highlighting the need to reduce mercury exposures of some pregnant women in the state.

What has been done

Building on the work of previous research with nanoparticles, U of M researchers used a storebought, memory foam sponge and coated it with a nano-layer of selenium. The resulting sponge can remove over 99.9 percent of mercury from lakes, rivers, storm water ponds, wetlands, and wastewater within seconds.

Results

The efficiency of the sponge was demonstrated by removing mercury to undetectable levels from tap, lake, and industrial water, regardless of pH conditions. Additionally, it meets all EPA standards for nonhazardous waste disposal by permanently binding the mercury into biologically inert, non-toxic complexes.

The demonstrated removal capacity will open up new opportunities to clean rain, surface and groundwater, and reduce mercury cycling at multiple stages. Both a US and international patent are currently pending.