Nanocrystals as stoichiometric reagents with unique surface chemistry. New adsorbents for air purification

Nanocrystals of MgO and CaO were prepared with high surface areas/gram, often as high as 500 m(2)/g [1] these materials were investigated as adsorbents for typical volatile organic compounds that are representative of air pollutants. As a result of their high surface areas and their enhanced surface reactivity, nanocrystalline MgO and CaO have shown a remarkably high capacity to chemically adsorb such organic compounds. Compared to high surface area activated carbon, the most widely used material in this application, our nanocrystalline materials have shown much better adsorption in regards to the amount and the nature of adsorption. FT-IR investigation of acetaldehyde adsorption on AP-MgO indicates that a multilayer dissociative adsorption fakes place as a result of surface interaction with the carbonyl bond followed by aldehydic hydrogen dissociation. (C) 1999 Acta Metallurgica Inc.