ACTIVITY OF ALUMINA SUPPORTED Fe CATALYSTS FOR N2O DECOMPOSITION: EFFECTS OF THE IRON CONTENT AND THERMAL TREATMENT

The activity of Fe 2 O 3 /Al 2 O 3 catalysts prepared by impregnation of Al 2 O 3 with different amounts of Fe and calcination temperatures (650 and 900 ºC) in the direct N 2 O decomposition reaction was studied.High calcination temperature was introduced to study the effect of "aging", which are the conditions prevailing in the process-gas option for N 2 O abatement.The catalysts were characterized by BET, XRD, UV-DRS, and H 2 -TPR.The incorporation of Fe promotes the alumina phase transition (g-Al 2 O 3 to a-Al 2 O 3 ) when the catalysts are calcined at 900 ºC, which is accompanied by a decrease in the specific area.The activity of the catalysts and the specific surface area depend on Fe loading and calcination temperature.It was found that highly dispersed Fe species are more active than bulk type Fe 2 O 3 particles.We conclude that Fe 2 O 3 /Al 2 O 3 catalysts prepared by impregnation method are active in the decomposition of N 2 O, to be used at low or high reaction temperatures (tail-gas or process-gas treatments, respectively), as part of nitric acid production plant.