Removal of 2‐Heptanone by Dielectric Barrier Discharges – The Effect of a Catalyst Support

Abstract

Abstract Summary: 2‐heptanone is representative of a class of odorous molecules. Recent studies have shown that by adding a catalyst to a dielectric barrier discharge (DBD) plasma, the elimination of 90% of this molecule can be achieved with low consumption of electric energy, at room temperature, for concentrations below 1 000 ppm. In the presented work, the removal of the ketone by DBD, both in dry air and within a slice of a honeycomb monolith of cordierite without a catalyst, was studied. In both experiments, the discharge was operated in a plane‐to‐plane geometry with a discharge volume of 10 cm 3 . A high voltage, bipolar pulse generator (40 kV max, 1–140 Hz frequency range) was used. In dry air, it was found that 2‐heptanone is almost totally removed (>95%) for a specific deposited energy of about 500 J · l −1 , but this elimination is less effective in the porous cordierite reactor (80%) for the same energy. This effect is explained by the very different spatial distribution of the plasma within the discharge volume, as seen using a CCD camera. Moreover, the adsorption‐desorption equilibrium of the molecule at the surface of the material is greatly influenced by the discharge. 2‐Heptanone removal as a function of the specific energy for the DBD both in dry air and in the cordierite catalyst support. magnified image 2‐Heptanone removal as a function of the specific energy for the DBD both in dry air and in the cordierite catalyst support.