The selective adsorption of NO on synthetic iron(III) oxide hydroxides

In order to verify the mechanism of selective adsorption of NO from mixed gases on synthetic crystals of α-, β- and γ-FeOOH, the following measurements were carried out at 30 °C: (1) the amount of chemisorption of NO, SO2 and CO2 on each FeOOH polymorph which is prechemisorbed by one of the gases, (2) the amount of “exchange” adsorption between NO and SO2, when a gas is introduced to the surfaces preoccupied by chemisorption of another gas, and (3) the comparison of the sum of chemisorption values measured separately for NO, SO2 and CO2 with the total chemisorption from mixed gas systems NO-SO2 and NO-CO2. The interaction between adsorbate molecules and FeOOH surface has been discussed to deleate probable positions of chemisorption of each adsorbate on predominant crystal surfaces of FeOOH.