Feasibility of application of iron zeolites for high-temperature decomposition of N2O under real conditions of the technology for nitric acid production

FeOx/Al2O3 catalysts for high-temperature decomposition of N2O under conditions of NH3 oxidation in nitric acid production

“…A decreasing temperature sequence from 900 down to 400 °C was used with a stabilization time of 60 min to obtain the steady-state values. The total catalyst volume was always 0.2 cm 3 and at the overall flow rate of 350 cm The catalytic experiments data at constant GHSV were obtained at identical hydrodynamic conditions for all experiments. These data were reprocessed to constant weight hour space velocity (WHSV) in order to establish the relationship between the structural properties and the catalytic activity.…”

“…1,2 The newly proposed alternative technique of direct N 2 O catalytic decomposition immediately after the ammonia burners has shown great promise. 3,4 Such an approach minimizes the economic demands for the process and at the same time allows relatively convenient approach for retrofitting the existing technology. Nevertheless, this approach exposes any potential catalysts to very harsh conditions such as the high temperatures of approximately 750-930 °C and to a gas mixture containing not only 7002000 ppm of N 2 O but also 10 vol.% of NO, 15 vol.% of H 2 O and approximately 2 vol.% of O 2 .…”

“…3 (hematite) thin layers, nanoparticles or clusters with sizes <10 nm, where the Morin transition is suppressed.47, 48The sextet S2 with IS = 0.480.50 mm s 1 , QS > 0 and the B hf = 53.454.1 T is ascribed to the α-Fe 2 O 3 (hematite) thin layers or nanoparticles with the sizes > 10 nm below Morin transition 47,48. The sextet S3 with large linewidths and IS = 0.390.45 mm s h coordination in θ-Al 2 O 3 (or δ-Al 2 O 3 ).…”

“…The sextet S3 with large linewidths and IS = 0.390.45 mm s h coordination in θ-Al 2 O 3 (or δ-Al 2 O 3 ). In Refs 3,7,[39][40][41]51.…”

Nitrous Oxide Adsorption and Decomposition on Zeolites and Zeolite-like Materials

“…The main disadvantages revealed, for example, by the Cu-catalysts for N 2 O decomposition are their low thermal stability (they irreversibly lose the activity after overheating to T > 870 K) and poor tolerance to admixtures of H 2 O, CO, CO 2 , and hydrocarbons, which are present in real gas mixtures and act as poisons. The behavior of catalysts definitely depends on the presence of water vapor in the feed, as well as other residual components (NO, O 2 , NO 2 ) that may interfere with the N 2 O decomposition process [24]. However, in the mixture, we will limit our scope with the model conditions, without the introduction of other potentially important ingredients.…”