Method for decontamination of contaminated solid with polychlorinated dibenzodioxine and/or polychlorinated dibenzofuran

PURPOSE: To effectively remove contamination of polychlorinated dibenzodioxin(PCDD) and polychlorinated dibenzofuran(PCDF) from solids by bringing contaminated solids with a hydrogen peroxide-contg. gas and a hydrogen peroxide-contg. aq.soln. into mutual contact under an oxidative condition of PCDD and PCDF until effective attainment of decontamination. CONSTITUTION: Contamination is removed from solids contaminated with PCDD and/or PCDF where the contaminated solids are brought in mutual contact with a hydrogen peroxide-contg. gas or a hydrogen peroxide-contg. aq.soln. selected from a H2 O2 -aq.soln. and a sodium percarbonate aq.soln. under an oxidative condition until effective attainment of decontamination. The solids consist of a series of oxides, silicates, zeolites, sludge and dust brought about from waste incinerators and metal processing industry, and active carbon. Further, the treatment of solids is performed by using 10-50 wt.% hydrogen peroxide aq.soln. at 10-95 deg.C.