Obtaining New Porous Materials by Self-Propagating High-Temperature Synthesis and Using Them as Neutralizing Catalysts in Vehicles

Abstract

At present, vehicle exhausts are among the major factors of environmental pollution. This problem is particularly acute in developing countries, where the share of used cars is high because the catalytic converters in used cars are partially or often completely out of order, which leads to the increase of toxic substances in the air such as carbon monoxide, nitric oxides, and hydrocarbons. We used the SHS method to obtain a new type of catalytic substrate, in which precious metals (platinum, palladium, rhodium) can be partially or completely replaced with metals such as copper, nickel, chromium, etc. When obtaining the catalytic substrate by the SHS method, the correct selection of a chemical composition of the initial charging material of the reaction is a determining factor that ultimately leads to obtaining products with the desired properties. Due to the high degree of dispersion of additive metals (copper, chromium, nickel, etc.), they do not participate in the reaction, therefore, they do not form chemical compounds, and they are evenly distributed in the final product, which significantly increases the quality of their catalytic activity. The porosity of the obtained sample is significantly affected by the density of the initial sample. By changing the initial porosity of the sample, it is possible to vary the porosity of the final product from 5 to 45%. Application of the proposed technology reduces the neutralizer-catalyst’s production cost and solves the problem of its scarcity. The obtained materials can be used in all types of vehicles with internal combustion engines, as well as in enterprises where catalytic purification of exhaust gases and liquids takes place.