Selenium is one of the most volatile and toxic byproducts produced by coal-fired power plants.
An essential trace element for humans and other animals, large quantities of selenium can cause infertility and damage to the liver, kidneys and lungs. About 2,500 tons of selenium are discharged into the atmosphere each year in the United States alone. Regulations being proposed by the Environmental Protection Agency will seek to control emissions of selenium and other metals found in fly ash and flue gas, said Liang-Shih Fan, professor and chair of chemical engineering at Ohio State. Fan and Suhas Mahuli, a post-doctoral researcher in chemical engineering, have studied ways to capture selenium from flue gas before it escapes into the atmosphere. The researchers found that hydrated lime, which has been shown effective in controllingsulfur dioxide emissions in flue gas, can also be used to reduce selenium.