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Information × Registration Number 0217U001127, 0114U000942 , R & D reports Title The development of scientific bases of creating a new generation of catalysts for NOx emissions abatement in gas emissions of mobile and stationary sources popup.stage_title Head Sergiy O. Soloviev, Кандидат біологічних наук Registration Date 24-01-2017 Organization L.V.Pysarzhevsky Institute of Physical Chemistry of National Academy of Science of Ukraine popup.description2 The influence of water vapor and sulfur dioxide on the activity of developed Ag/Al2O3/cordierite catalysts in the process of SCR of NOx with C2, C4 oxygenates and C3, C8 hydrocarbons was studied. Reduction of NOx with ethanol in the presence of H2O (6 vol.%) in the reaction mixture (RM) causes a decrease in conversion of NO on 5-10% in the temperature range 200-450 °C, and in the process of SCR with butanol - on 2-7 % at 250-400 °C. After removing water vapor from the reaction mixture activity of silver-alumina catalysts increases to performance achieved in the absence of H2O in RM. In the presence of sulfur dioxide the temperature of 95% NO reduction with ethanol over 0,5%Ag/54%Al2O3/cordierite is increased on 120 oC. After catalyst regeneration (heating at 550 °C in a flow of helium), its activity is reduced almost to initial values. During SCR of NOx with butanol in the presence of H2O and SO2 NO conversion decreases to 80% and temperature increases on 170°. In the case of selective reduction of NO with C3, C8-alkanes conversion of NO is reduced on 15-20% and is 44% at 480 °C (SCR octane) and 40% at 540 °C (propane). Lower activity of the catalyst at temperature <300 °C may be caused by the formation of silver sulfates that inhibit the formation of surface nitrate adducts and reduces the rate of interaction with enolic species. At temperatures >400 °C the conversion of NO in the presence of sulfur dioxide increases, which is associated with deactivation of sites of deep oxidation of reducing agent - Ag nanoparticles. It is shown that BEA and MOR zeolites, modified by indium oxide, show high activity in the SCR of nitrogen oxides (I, II) with propylene, including in the presence of water vapor. This is caused by required concentration of Bronsted acid sites on the catalyst surface where activation of hydrocarbon-reductant and nitrous oxide occurs. Technological protocols of preparation of structured catalysts Ag/Al2O3/cordierite and Pd/Co3O4-CeO2/cordierite were transferred to state enterprise "Catalysis and ecology" of IPhCh of NASU.5481 Product Description popup.authors Бойчук Тетяна Михайлівна Кирієнко Павло Іванович Попович Наталія Олексіївна popup.nrat_date 2020-04-02 Close