Feb 12, 2018

Chemists to Potentially Mine Silver from Laundry Wastewater

The toxic metal poses a threat to wildlife

Chemists have attempted a new process to extract silver from laundry wastewater

Two environmental engineers have reportedly developed a way to successfully extract silver from laundry wastewater. Such wastewater can often carry significant amounts of the toxic metal, and being able to separate it from the wash water would make positive strides in preserving wildlife.

This new process would not only improve environmental conditions, but the silver could then be repurposed for a variety of uses. Silver is abundant in laundry wastewater due to nano bits of silver added to many different fabrics by manufacturers in order to fight odor. This wastewater is eventually released into any number of bodies of water, potentially posing a threat to the environment.

“[Researchers] are walking a fine line between silver’s desirable properties and its potential toxicity to the environment,” said Silke Schmidt, a science journalist. “Products embedded with nano-silver tend to lose some of their silver coating every time they’re laundered.”

The new process uses resin to trap the silver ions present in the wastewater. The resin is then made into beads and packed into cylinders known as columns. Liquids, such as wash water, then get pumped through the columns.

Tests of silver removal using this technique has been far from perfect, as the process of ion exchange between the resin and the wash water poses a number problems, specifically that any number of ions may be exchanged between the resin and the wastewater, not just silver.