Dyes are widely used in industries such as textiles, cosmetics, food processing, papermaking and plastics. Globally, we produce about 700,000 metric tons — the weight of two Empire State Buildings — of dye each year to color our clothing, eye shadow, toys and vending machine candy.
Dyes are widely used in industries such as textiles, cosmetics, food processing, papermaking and plastics. Globally, we produce about 700,000 metric tons — the weight of two Empire State Buildings — of dye each year to color our clothing, eye shadow, toys and vending machine candy.
During manufacturing, about a tenth of all dye products are discharged into the waste stream. Most of these dyes escape conventional wastewater-treatment processes and remain in the environment, often reaching lakes, rivers and holding ponds, and contaminating the water for the aquatic plants and animals that live there. Even just a little added color can block sunlight and prevent plant photosynthesis, which disrupts the entire aquatic ecosystem.
A team led by the University of Washington has created an environmentally friendly way to remove color from dyes in water in a matter of seconds. The technique was described in a paper published online in June in the journal Applied Catalysis B: Environmental.
Read more at University of Washington
Image: The UW’s sponge-like material, left, is made from wood pulp and small bits of metal that can remove color from dyes in water within seconds. CREDIT: Mark Stone / University of Washington
