Some catalytic applications of aerogels for environmental purposes

Abstract To protect our environment, catalysts are useful for the treatment of pollutants once they have been generated, or to prevent or at least to minimize their formation. To meet these requirements, very highly divided supports and active phases are necessary for satisfactory results. In particular, nanoparticles such as those obtained by sol–gel chemistry combined with supercritical drying methods (“aerogels”) may develop specific catalytic properties from the points of view of textural and thermal qualities. Some examples of gas and liquid phase catalysis such as SCR, deNO x , hydrocarbon combustion and the elimination of nitrophenols and cyanide wastes in water are presented here.