Reaction behaviors of CH3CN catalytic combustion over CuCeOx-HZSM-5 composite catalysts: The mechanism of enhanced N2 selectivity

•High N2 selectivity was achieved on CuCeOx-HZSM-5 composite catalysts.•The introduction of HZSM-5 enhanced the hydrolysis of CH3CN and NCO(a).•The enhanced N2 selectivity could be attributed to the internal SCR reaction.•The synergism between CuCeOx and HZSM-5 facilitated the internal SCR reaction.