A review of CFC and halon treatment technologies – The nature and role of catalysts

The purpose of this review article is to provide readers with an account of CFC and halon treatment technologies as depicted in the patent and open literature. Destruction technologies, in which halons and CFCs are converted into species such as CO₂, HX or X₂ (X = Br, Cl, F), are treated less extensively. Emphasis has been placed on conversion processes, which aim at transforming (rather than destroying) CFC or halon into environmentally benign and useful products. It has been found that catalytic hydrodehalogenation over transition metal based catalysts, Pd in particular, has great potential for conversion of CFCs and halons to hydrofluorocarbons. In this regard, the focus of this review is on catalytic hydrodehalogenation, including an assessment of reaction mechanisms, catalytic activity, selectivity and durability.