Effective destruction of (poly)chlorinated aromatic compounds using aluminium alloys

Abstract

Halogenated aromatic compounds (Ar-Xs) are widely used as solvents, starting materials, intermediates or active compounds in the production of specialty chemicals like dyes and pigments, remedies and pesticides. In some cases Ar-Xs are produced as undesirable by-products. However, Ar-Xs have often biocidal properties, they are typical recalcitrant compounds in environment. Nowadays, the waste streams contaminated with Ar-X are incinerated in hazardous waste incinerators, this thermal oxidation process is accompanied by formation of very toxic and very stable polychlorinated dioxins and dibenzofurans. PCDD/Fs have played a main part in the debate about waste incineration for many years. In many countries, including Czech Republic, public opinion is generally against incineration of hazardous waste. We proved that reductive dehalogenation enables simple, cheap and very effective destruction of Ar-X to the corresponding Ar-H using aluminum alloys at room temperature and ambient pressure. Produced Ar-H are biodegradable, produced inorganic waste is fully recyclable (Ni or Cu slurry) or applicable in another processes (aluminum hydroxide).