Functions and uses
The main function of SCR catalyst is to remove nitrogen oxides from ship exhaust. Its reaction is a complex reaction system. It is sensitive to reaction conditions (temperature, space velocity, gas composition, etc.) and has a temperature window.
Its principle of action is as follows:
4NH3+4NO+O2→4N2+6H2O （Standard SCR reaction）
2NH3+NO+NO2→2N2+3H20 （Rapid SCR reaction）
8NH3+6NO2-→7N2+12H2O （NO2 overdose）
Performance characteristics
Vanadium-based SCR catalyst (V-SCR) has a wide temperature window (250-500 C), good sulfur resistance and lower durability than zeolite catalyst. The oxides have biological toxicity, and there is a risk of leakage at high temperature (> 550 C), which is harmful to human body. The improved V-SCR catalyst has been greatly improved in terms of high temperature leakage.
Durability:
Greater than 20000h
V-SCR performance description:
Toxic NOx (x=1,2) is reduced to non-toxic N2 and H2O by the action of reducing agent NH3.
The temperature window of V-SCR catalyst is very wide, and the conversion of NO_x is very good in the temperature range of 200-550 (?) C, especially in the range of 300-450 (?) C, the average conversion is more than 80%.
Applicable standard
V-SCR is widely used in national V and national V stages. There will also be a market for off-road T4 (mainly based on engine exhaust temperature control).
Working conditions:
Working temperature below 550 C
The monolithic catalyst is suitable for space velocity of 0-100 kh-1.
