PROCESS FOR PREPARING VANADIUM-BASE SCR CATALYST COATING FOR PURIFYING TAIL GAS OF DIESEL VEHICLE

摘要

The present invention relates to a method for preparing a catalyst coating for removing nitrogen oxides from tail gas of a diesel vehicle. The catalyst is composed of V2O5, WO3 and TiO2. Fresh and aging sample bench tests show that the coating has a high nitrogen oxide removal rate (≥85%) at 250°C to 500°C, and the coating passes the ETC and ESC working condition cycle tests and conforms to the national IV emission limit. In the process, size mixing is conducted on the precursor to obtain catalyst slurry at one step, and the catalyst slurry is subjected to primary coating (the coated amount ≥210 g/L), drying, and roasting to obtain a honeycomb catalyst. The process is simple, has a low cost and high stability, and is suitable for mass production.