Recently, increasing fine dust reduces our quality of life and worsens our health. In this situation, government and many people try to remove the nitrogen oxide($NO_x$) which accounts for 20% of fine dust. Also transportation accounts for 50% of exhausting nitrogen oxide($NO_x$), 60% of this nitric oxide is exhausted by the car. Government is constantly striving to reduce the release of nitrogen oxide, so that they have shut down coal-fired power plants. However, this could be another cause of energy shortage. Furthermore, the regulation of $NO_x$ emission of diesel car is becoming more stricter, the situation of the ship is not much different. The army vehicle, especially tank, require an output of 1200HP so that electricity or hydrogen based engines are not available at this time. So the $NO_x$ emission should be minimized while the internal combustion engine continue to use.
The reliable technology is Selective Catalytic Reduction(SCR) currently applied in market for reduction of $NO_x$ emission. This technology is applied to power plants and vehicles to satisfy some of the strict regulation. However, the efficiency of SCR is reduced due to failure to reach the catalytic activity range during initial start-up or the city driving. The more serious problem is that this technology cannot satisfy more stricter regulations so that first the low-temperature and highly-activity catalysts is fabricated, second the use of catalysts should be drastically reduced and third innovative catalyst device that is minimized catalysts contamination and exceeds the performance of the current catalyst device(Honeycomb support) should be developed.
Therefore, The first chapter reports on developing catalyst that was based on Fe-Mn and low-temperature SCR catalyst on stainless mesh. In the second chapter, SCR catalyst combined with the Impeller that was developed in our laboratory so that significantly increased the contact between gas and solid, also solve the problem of pressure drop.