Component optimization and performance of Ti-Al-Si-O_x deNO_x catalyst carrier

A series of Ti-Al-Si-O_x deNO_x catalyst carriers were prepared by extrusion method and tested for selective catalytic reduction (SCR) of NO with NH₃. The Ti-Al-Si-O_x formulas were designed and optimized by orthogonal experiments, and the specific surface area, pore volume and size distributions, micro-morphology and solid-phase structure of the carriers were characterized by N₂-BET, ESEM and XRD, respectively. Moreover, the water adsorption, open porosity and bulk density of the carriers were measured by Archimedes method. Results showed that the catalytic activity for NH₃-SCR of NO and the axial crush strength of the TiAl_0.2Si_0.1O_x carrier matched the best when the Ti/Al/Si molar ratio was equal to 1:0.2:0.1. Under gas hourly space velocity (GHSV) of 7200 h^-1, the TiAl_0.2Si_0.1O_x obtained more than 80% NO removal in active temperature range of 450-550℃, and obtained the maximum catalytic activity of 85.8% at 494℃. The axial crushing strength of the TiAl_0.2Si_0.1O_x was 6.17 MPa, its specific surface area was 89.1 m²/g, its open porosity was 63.0%, its water adsorption was 48.3%, the most probable meso pore distribution was 8.1 nm and the second probable pore distribution was 3.7 nm. In conclusion, the TiAl_0.2Si_0.1O_x deNO_x catalyst carrier possesses excellent performance.