EFFECT OF NOx REDUCTION CATALYTIC CONVERTORS IN LEAN BASED ENGINES - A REVIEW PAPER
Keywords:
Air pollution, NOx emissions, lean air to fuel ratio, catalytic convertorsAbstract
The awareness regarding the air pollution and its effects on our environment has inspired many
researchers. Tail-end emission of pollutant gases such as NOx
, CO, unburnt hydrocarbons (HC), etc. from the engines
are the biggest contributors in air pollution. Engines with a lean air-fuel ratio have better fuel efficiency and a low
operating cost. However the NOx emission from a lean engine is difficult to control. These economical engines produce
exhaust fumes that are particularly rich in oxygen and therefore the conventional three-way catalytic converter is not
suitable for converting the generated NOx
into nitrogen. This review paper discusses the usage of the NOx storage
catalytic convertor as a measure to reduce NOx emissions from such oxygen rich (higher a/f ratio) engines.