Abstract: Air polluted with potentially harmful chemical and biological matter is purified and pollutants degraded to less hazardous substances by a combined chemical and electrochemical process. Scrubber liquid-electrolyte circulated between scrubber and electrolyzer zones containing an electrochemically renewable degradant complexes or oxidizes the pollutants with the aid of an electrochemical cell in the electrolyzer zone which also reactivates the degradant in the scrubber liquid for recycling. Adsorption of insoluble organics is enhanced by stable surfactant additives to the scrubber liquid-electrolyte. Surprisingly, the electrochemical cell performs efficiently without separators or membranes when the non-working cathodes comprise Magneli phase substoichiometric titanium oxides which preferentially generate hydrogen instead of reducing redox couples to their inactive lower valence state.

Abstract: Air contaminated with chemical and biological pollutants is purified by treating chemically and electrochemically in a closed system minimizing the generation of by-products for disposal. Pollutants are treated in a scrubber zone with a scrubber liquid-electrolyte comprising pollutant degrading metal ions or complexed with inert metal ions and degraded either in an electrolyzer zone or in both the scrubber and electrolyzer zones where spent scrubber liquid-electrolyte is regenerated for further cleaning.