Effect of the microstructure of an iron powder on the reactivity with trichloroethylene

Reductive degradation of chlorinated hydrocarbons in aqueous solutions by zero-valent iron is affected by many factors. The process may be affected by the surface condition of the iron, solution conditions such as pH, dissolved oxygen, anion species, and conductivity, and the type of chlorinated hydrocarbons. The effect of the microstructure of an iron powder prepared by a water spray atomizing process, which is commonly used in producing a commercial base iron powder for powder metallurgy, on the reactivity with trichloroethylene (TCE) was studied. Increasing the sulfur content of atomized iron powder improved the TCE degradation rate. However, with higher manganese contents, the effect of the sulfur content was less pronounced. With an iron powder with a manganese content of 0.7%, sulfur and manganese were detected in the same area. The relationship between the degradation rate constant of the TCE and the surface area was linear with the two atomized iron powders. This is an abstract of a paper presented at the 224th ACS National Meeting (Boston, MA 8/18-22/2002).