Li_2Cu_2(MoO_4)_3/TiO_2 + SiO_2/Ti Compositions for the Catalytic Afterburning of Diesel Soot

摘要

Two methods were used to obtain a catalytically active oxide coating on the surface of titanium for the catalytic afterburning of diesel soot: plasma electrochemical formation of an oxide film on the surface of titanium and extraction pyrolytic deposition of the Li_2Cu_2(MoO_4)_3 compound. The Li_2Cu_2(MoO_4)_3/TiO_2 + SiO_2/Ti compositions synthesized by the single-step extraction pyrolytic treatment of the oxidized surface of titanium ensured a high burning rate of soot of ～300℃. The subsequent deposition of Li_2Cu_2(MoO_4)_3 lowers Qthe activity of the catalyst, due probably to the growth of molybdate phase crystallites and the filling of open oxide film pores. Double lithium–copper molybdate is able to reduce appreciably the concentration of CO in the oxidation products of soot. The advantages of these methods are the possibility of forming high-cohesion durable coatings on surfaces of any complexity, the simplicity of their implementation, and high productivity and low cost. The obtained results can be recommended for use in developing methods for creating composite coatings on catalytic soot filters.