Combination of nonthermal plasma and low temperature-C₃H ₈-selective catalytic reduction over Co-In/H-beta catalyst for nitric oxide abatement

Nitric oxide (NO_x) abatement by a two-stage system composed of nonthermal plasma (NTP) followed by the selective catalytic reduction with C₃H₈ (C₃H₈-SCR) over the Co-In/H-beta catalyst was investigated at a relativity low temperature range from 548 to 598 K. The combination system shows better synergy at low temperature. Optimum active temperature of Co-In/H-beta in the complex system is shifted from 648 to 598 K compared with that in C₃H₈-SCR. The highest NO_x conversion is over 98%. In contrast to treatment by the NTP, the two-stage system converts mostly NO to nitrogen; without NO ₂, nitrogen-containing and organic components formed. The synergetic effect of the combination system is enhanced with the C₃H₈ concentration and O₂ content.