Chemical detoxification of toxic chlorinated aromatic compounds

A method for the reduction of the content of chlorinated dibenzo-p-dioxins in reaction products to virtually zero consisting of

• (1) reacting a high boiling still bottom residue containing chlorinated dibenzo-p-dioxin resulting from the production and distillation of 2,4,5-trichlorophenol with an amount, in excess of stoichiometrical based on the total organic halogen content, of alkaline reactants selected from the group consisting of:
• (a) alkali metal alcoholates of alcohols selected from the group consisting of alkanols having from 1 to 5 carbon atoms, polyalkoxyalkane glycols having from 4 to 20 carbon atoms, alkanepolyols having from 2 to 5 carbon atoms and 2 to 3 hydroxyls, and monoalkyl ethers of said alkanepolyols with alkanols having from 1 to 4 carbon atoms and
• (b) mixtures of said alcohols with alkaline reactants selected from the group consisting of alkali metal hydroxides and carbonates,
• at a reaction temperature of from 140.degree. C. to 220.degree. C. for a time sufficient to convert substantially all the organic chlorine of the halogenated aromatic compounds in the still bottoms into inorganic chloride, and recovering the still bottoms virtually free of chlorinated dibenzo-p-dioxins
• (2) substantially dissolving the still bottoms virtually free of chlorinated dibenzo-p-dioxins in water,
• (3) extracting the aqueous mass with an organic solvent for chlorinated dibenzo-p-dioxins immiscible in water,
• (4) discharging the extracted aqueous mass vitually free of chlorinated dibenzo-p-dioxins,
• (5) recycling said organic solvent extract to step (1), and
• (6) recovering said organic solvent from said reaction step 1 by distillation and condensation.