Photo-induced Dissolution of Metal Ions from Fly Ash Particles in Acidic Media

A significant amount of the particulate matter found in polluted regions of Northeast India is composed by fly ash aerosols. It has been suggested that fly ash may be a source of trace elements in tropospheric water. Since some components of fly ash are photoactive species, the acidic media and solar radiation can affect the rate and yield of metal dissolution in tropospheric water. We carried out dissolution studies to examine the effect of acidic media and light on the dissolution rate and yield of metal ions from Northeast India fly ash. A suspension of fly ash in nitric acid and hydrochloric acid was studied under broad band radiation (\u3e 300 nm), under the photolysis wavelength of nitrate (310 nm), and under dark conditions. Normalized yields of metal ions leaching (an approximation to quantum yields) from Indian fly ash was found to be affected by both the acid media and the solar radiation wavelength