Simultaneous catalytic reduction of N 2 O and NO x for tertiary N 2 O abatement technology: A field study in a nitric acid production plant

To investigate the feasibility of the simultaneous abatement of N 2 O and NO x in a single reactor, this field study was performed in a nitric acid production plant. An Fe/BEA powder catalyst prepared by Fe ion‐exchange with steam‐treated BEA zeolite was extruded in pellets and honeycombs. In the simultaneous reduction of N 2 O and NO x , the pellet‐ and honeycomb‐type catalysts showed more than a 90% and 95% conversion of N 2 O and NO x , respectively, at a reaction temperature between 350 °C and 380 °C which is typical for the DeNO x process. The catalytic performance of the pellets and honeycombs was also stable during the reactor operation period. With higher N 2 O and NO x conversions of over 90%, NH 3 concentration in exhaust gas streams can be reduced to satisfy domestic regulations for air pollutant emissions. Accordingly, it is suggested that the simultaneous reduction of N 2 O and NO x in a single reactor with the Fe/BEA catalyst may be a reasonable option for a tertiary abatement technology for nitric acid production plants. Novelty or Significance: The simultaneous catalytic reduction of N 2 O and NO x in a tail gas from a nitric acid production plant was investigated with Fe/BEA catalysts prepared by Fe ion‐exchange with steam‐treated BEA zeolite. Pellet‐ and honeycomb‐type catalysts were applied to abatement using NH 3 as the reducing agent. Over 90% of N 2 O and NO x from the nitric acid production process was simultaneously removed from a single reactor at a reaction temperature between 350 °C and 380 °C. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 451–456, 2019