Abstract
To carry out the decomposition of chlorinated aromatic compounds such as dioxins, which are hard to decompose at room temperature, nanoscale α-Fe · Fe3O4 composite particles were synthesized via α-FeO(OH) obtained by the reaction of ferrous sulfate and sodium carbonate aqueous solutions and contained 0.25 wt% precious metals (Pt, Pd, Rh and Ru). As the result of the decomposition of chlorobenzene (CB) using the composite particles containing precious metals, it was shown that Rh · α-Fe · Fe3O4 and Ru · α-Fe · Fe3O4 composite particles exhibit superior dechlorination function. Ru · α-Fe · Fe3O4 composite particles were selected because of their low price. For the application of dioxin decomposition at room temperature in contaminated soil, an extractive reagent was selected. Successively, the decomposition of dioxins in extracted-reagent- suspended soil using Ru · α-Fe · Fe3O4 composite particles was carried out at room temperature for seven days, and the initial Toxicity Equivalency Quantity (TEQ) values of dioxins in the solvents and soils decreased to 41-63% after the decomposition.
