Positive DC corona discharge in a hemicylindrical discharge reactor was applied to mixtures containing N 2 , NO, O 2 , CO 2 and H 2 O, while an NO x chemiluminescence analyzer and an IR spectrometer were used to evaluate the concentration changes and analyze the products of the process in the discharge chamber. The removal efficiency of 89% for NO and the energy cost of 350 eV/molecule were achieved. Special attention was paid to the influence of CO 2 on discharge, its character, performance and products of the process. In addition to the main components of the gas mixture (NO, NO 2 , CO 2 , CO etc.), other compounds and functional groups (e.g., amides I-III, imides, NCO) have been identified among the products of the process.