Investigation of operating parameters on CO₂splitting by dielectric barrier discharge plasma

Abstract

Experiments of CO 2 splitting by dielectric barrier discharge (DBD) plasma were carried out, and the influence of CO 2 flow rate, plasma power, discharge voltage, discharge frequency on CO 2 conversion and process energy efficiency were investigated. It was shown that the absolute quantity of CO 2 decomposed was only proportional to the amount of conductive electrons across the discharge gap, and the electron amount was proportional to the discharge power; the energy efficiency of CO 2 conversion was almost a constant at a lower level, which was limited by CO 2 inherent discharge character that determined a constant gap electric field strength. This was the main reason why CO 2 conversion rate decreased as the CO 2 flow rate increase and process energy efficiency was decreased a little as applied frequency increased. Therefore, one can improve the CO 2 conversion by less feed flow rate or larger discharge power in DBD plasma, but the energy efficiency is difficult to improve.