Iron particles for purifying contaminated soil or ground water, process for producing the iron particles, purifying agent comprising the iron particles, process for producing the purifying agent and method of purifying contaminated soil or ground water

摘要

Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of &agr;-Fe phase and Fe₃O₄ phase, and having a BET specific surface area of 5 to 60 m²/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.