Adsorption Activity of NO on Iron Oxide-Dispersed Porous Materials

Abstract

Iron oxide-dispersed activated carbon fibers (ACF), granular activated carbons, zeolites, and silica gels have been prepared in order to develop good adsorbents for NO. The adsorption isotherms of NO on these samples have been measured at 303 K over an NO pressure range up to 80 kPa. The iron oxide-dispersed ACF samples (α- and β-ACF), obtained under the synthetic conditions employed for the preparation of α-FeOOH and β-FeOOH respectively, show very high adsorption activity for NO; their adsorption rates and capacities are much greater than those for untreated activated carbons, zeolites and silica gels. Furthermore, α- and β-ACF are effective in adsorbing NO from a 5 ppm NO/N2 gas mixture, reducing the concentration from 5 ppm to less than 1 ppm at 303 K after just one circulation with a flow velocity of 200 ml/min.