Method of removing nitrogen oxides from exhaust gas mixtures

摘要

A method of removing nitrogen oxides (NOx) from exhaust gas mixtures is described. The removal of NOx from exhaust gas mixtures is accomplished by exposing the exhaust gas mixture, in a manner that does not substantially impede the gas flow, to a ceramic material containing from about 75% to about 95% by weight silicon carbide and from about 0.3% to about 10.0% silica. A reduction of at least 85% of NOx from the mixture is to be expected and reductions up to 95 to 100% are attainable. Ceramic mixtures containing silicon nitride in amounts between about 10% and about 30% are found to reduce the amount of NOx in exhaust gases at temperatures as low as 200 DEG C.