Abstract: To reduce NOx emission on MIP-CGP unit in CNPC Daqing refinery, a commercial trial of a novel specially formulated catalyst CGP-1DQ with the function of NOx emission reduction was performed. The results show that when the new CGP-1DQ in catalyst inventory reaches about 40%, NOx emission in flue gas is decreased by 42% to about 656 mg/m3 compared with the level of NOx emission (1 134 mg/m3) in the interrupted period during the trail. However, if compared with the base condition (1 900 mg/m3), NOx emission is decreased by more than 65%. In addition, no negative influence on product distribution and unit running are observed during the operation.

Key words: flue gas, NOx, cracking catalyst, product distribution