Pollutant Control by Catalytic Methods

Catalysis is an effective and economical approach to reduce air pollutants and the development of high-performance catalysts is a critical factor in the employment of catalytic pollutant control technology. Considerable efforts have been made to develop catalytic technologies capable of reducing pollutants in flue gas with NH3-SCR being successfully industrialized for NOx abatement since the late 1970s. However, flue gas pollutants vary by fuel and can include varying concentrations of NOx, SOx, VOCs, and heavy metals. When combined with the varying temperature of flue gas and the source of pollutants, the effective removal of pollutants becomes challenging. Additional requirements have thus been suggested for the catalytic technology to efficiently remove multiple pollutants. In this chapter, the basic principles of SCR are first introduced. Some critical issues in SCR development, including the design of poison-resistant catalysts, catalysts exhibiting a wide working temperature window or low-sulfur conversion, and the industrial preparation and regeneration of deactivated catalysts, are then discussed in detail. Finally, research on and applications of simultaneous multi-pollutant catalytic treatments are presented.