CATALYST FOR REMOVING NOX FROM EXHAUST GAS OF LEAN-BURNING AUTOMOBILES OR INCINERATORS

摘要

The present invention relates to a catalyst for removing NOx contained in exhaust gas, more specifically to a catalyst for removing NOx using metal titanate as a support. The catalyst for removing NOx according to the present invention allows metal titanate to act as a support as well as an adsorption and storage agent (hereafter an adsorption/storage agent) of NOx in lean-burn conditions. Supported noble metals or transition metal components provide a catalyst function which helps adsorption/storage by oxidizing NOx into N02 in lean-burn conditions and participates in the reaction of reducing the adsorbed and stored N02 into N2 in fuel-rich conditions. The catalyst according to the present invention has twice the NOx storage amount of conventional catalysts, for example Ba, and enables effective removal even in operational conditions of a wider range than 150 - 700 °C . In addition, practical use which has been impossible until now is enabled due to the stable NOx removal capability even in conditions where SOx is present in exhaust gas.