Užití kalcinovaných LDH jako katalyzátorů pro odstranění emisí N2O

Mixed oxide catalysts were prepared by calcination of LDH containing as divalent ions Ni, Co, Cu and /or Mg and as trivalent ions Mn, Fe and/or Al. The highest conversion was reached over Ni-Al and Co-Mn-Al mixed oxides. N2O conversion decreased slightly with the presence of NO2 over Co-Mn-Al catalyst, but strongly over Ni-Al catalyst. Water vapor inhibited the N2O decomposition over all tested catalysts

Catalytic Decomposition of Nitrous Oxide over Calcined Hydrotalcite-like Compounds

Mixed oxide based catalysts prepared by the thermal decomposition of Hydrotalcite-like compounds were used in catalytic decomposition of nitrous oxide into nitrogen and oxygen. The catalytic reaction was performed in a fixed-bed reactor at 1000 ppm N2O inlet concentration in the temperature range 603 - 723 K. Ni and Co-containing catalysts showed high activity in nitrous oxide decomposition. A very poor activity was observed for Mg-Al mixed oxide catalyst. The prepared catalysts were characterized by the thermal analysis, powder X-ray diffraction, infrared spectroscopy, BET surface area measurement, temperature-programmed reduction and temperature-programmed desorption. The determined reaction rate constants of N2O decomposition were approximately proportional to the amount of reducible components and inversely proportional to the amount of strong basic centres of catalyst

Alkali Metals as Promoters in Co-Mn-Al Mixed Oxide for N2O Decomposition

The aim of presented contribution is evaluated of alkali metals promoter effect in Co-Mn-Al mixed oxide (molar ratio Co:Mn:Al=4:1:1) one the low temperature N2O catalytic decomposition

Catalytic Reduction of N2O Emissions.

Effect of mixed oxides prepared by decomposition of hydrotalcite precursors was studied in decomposition of N2O. In simulated proces conditions (presence of O2, NO, NO2, H2O) their activity and long-term stability was examined. The most active catalyst was that with 3 wt. % K

Cobalt-Containing Mixed Oxide Catalysts for Removal of N2O from Nitric Acid Plant Tail Gases.

Presented contribution summarizes our research dealing with cobalt mixed oxide catalysts for low temperature N2O caalytic deposition

Vliv alkalických kovů v kalcinovaném Co-Mn-Al LDH na katalytický rozklad N2O.

The effect of various amounts of potassium in Co-Mn-Al spinel catalyst on N2O decompositon was examined. Different catalytic performance of samples with different amount of K in th epresence of H2O and NOx could be related to changes in acidity and basicity of catalyst surface

New Catalyst for Removal of N2O from Nitric Acid Plant Tail Gases

In the present work, the Co-Mn-Al mixed oxide modified by K was prepared in the pilot plant scale for the first time and tested in real conditions. Result of N2O catalytic decomposition in the pilot plant reactor installed at the bypassed tail gas from the nitric production plant are shown and obtained kinetic datae used for modelling of full scale reactor for N2O emissions abatement

The balancing of NO concentration fluctuations by adsorption/desorption process on activated carbon

The present work deals with adsorption/desorption process of NO on activated carbon. The goal of the experiments was to determine under which conditions is the activated carbon bed able to damp down the concentration fluctuations of NO in the gas entering the bed. It was found out that the residence time necessary to balance out the input concentration fluctuations of NO increases along with the average concentration of NO. The minimum mean residence time of 3–9 min was found as necessary to level the average NO concentration ranging from 357 to 1428 ppm. The decisive parameters for the extent of attenuation are discussed in the terms of linear driving force model for fixed-bed adsorber dynamics