Possibilities of the Application of Catalyst Technologies for the Control of Particulate Emissions from Diesel Vehicles

Diesel exhaust particulate emissions have already emerged as a major environmental problem, especially in urban settlements. Development of a practically feasible particulate emission control technology can be considered as one of the most challenging tasks related to the after-exhaust treatment technologies. Application of an effective oxidation catalyst could be the most promising way for both, regeneration of diesel particulate filter (DPF), and instant oxidation of soluble organic fraction (SOF) of diesel soot. Although involvement of NO_x and SO₂ in soot oxidation has been found favorable for many catalysts, however, availability of their optimum quantity in exhaust for the soot oxidation, may not be always adequate, apart from their deleterious effects on catalyst stability and air environment. The present paper discuss about the various possibilities of catalyst applications for the control of particulate emissions. Laboratory evaluation data on the soot oxidation activity of perovskite type materials are also reported, which show good potential of such catalysts for the diesel exhaust emission control.