| abstract |
The invention discloses a preparation method and application of a CHA structure molecular sieve and a catalyst for denitration of tail gas, belonging to the field of chemical synthesis technology and its application. Using N,N,N-trialkyl-(norbornane-2-yl) quaternary ammonium compound as organic template agent to synthesize CHA molecular sieve, the molar ratio of the product silica to alumina ranges from 6 to 80 , the average grain diameter ≤ 500nm, the total specific surface area ≥ 400m 2 /g, the total pore volume ≥ 0.20ml/g, the micropore pore volume ≥ 0.10ml/g; the grain size in the crystal plane (‑210) direction is 50 ~160nm. After the molecular sieve is hydrothermally treated at 600-850 ℃, the four-coordinated aluminum accounts for ≥90% of the total aluminum, and the six-coordinated aluminum accounts for ≤10% of the total aluminum. The molecular sieve of the present invention has high hydrothermal stability without large crystal grains, and shows high nitrogen oxide reduction characteristics after exposure under high temperature and high humidity, especially in the temperature range of 200°C to 550°C. catalysts with nitrogen oxide reduction properties. |