Search for Effective Catalysts for the Development of Engines Based on the Products of Catalytic Decomposition of N2 O

摘要

The paper presents requirements for the N_(2)O decomposition catalyst and provides justification for the selection of components to develop its formulation.The methods to study the physical and chemical as well as catalytic properties of catalysts were developed,and the results of experimental studies on the properties of catalysts with different composition in the laboratory conditions were presented.The activity of samples of compact metal catalysts as well as samples of supported metal and oxide catalysts in the nitrous oxide decomposition reaction was studies.The methodology for determining the activity of catalysts in the decomposition reaction of N_(2)O is presented,as well as the design of an experimental reactor for determining the activity of the catalyst by the minimum temperature for the onset of the decomposition reaction of N_(2)O.In the course of the study,the following series of catalyst activity are determined in the N_(2)O decomposition reaction up to a temperature of 600℃:based on platinum group metals applied to the aluminum oxide carrier-Rh>Ru>Ir>Pt>Pd;based on simple oxides applied to the aluminum oxide carrier-CoO>Cr_(2)O_(3),MnO_(2)>CuO>ZrO_(2)>NiO>Fe_(2)O_(3).The following activity series for the most promising carriers are also determined:by the onset temperature of decomposition,ZrO_(2)>Al_(2)O_(3)-CaO>Al_(2)O_(3)-ZrO_(2)>Al_(2)O_(3)-AlN>θ-Al_(2)O_(3)>Al_(2)O_(3)-SiO_(2)>SiO_(2)>α-Al_(2)O_(3);by the rate constants of N_(2)O decomposition,Al_(2)O_(3)-SiO_(2)>Al_(2)O_(3)-AlN>ZrO_(2)>Al_(2)O_(3)>Al_(2)O_(3)-ZrO_(2)>Al_(2)O_(3)-CaO>α-Al_(2)O_(3)>SiO_(2).The paper presents the results of selecting the active component and carriers for the supported catalyst.The author proposes formulations of the nitrous oxide decomposition catalyst for bench testing in simulated engines.