Experimental study of positive corona discharge in mixtures of CO2 and N2

Positive corona discharge in mixtures of CO2 and N2 has been experimentally investigated using a coaxial wire-to-cylinder corona discharge reactor. Special attention has been paid to the stability of the corona current and to the generation of ozone and nitrogen oxides in time, which are influenced by the applied voltage and the ratio of CO2:N2 in the gas mixture

Negative corona discharge in mixtures of CO2 and N2: modeling and experiments

The decomposition of CO2 by the effect of negative corona discharge has been experimentally and numerically investigated for different admixtures of N2. The chemical kinetics model used in the simulation includes a wide variety of reactions between electrons, ions, atoms and molecules, such as ionization and recombination, electron+impact dissociation, dissociative recombination, dissociative attachment, thermal reactions between neutral chemical species, etc. Using the current+voltage characteristic as input data, the radial distributions of charged and neutral species has been predicted for different applied voltages and gas compositions. The generation of ozone, carbon monoxide and nitrogen oxides during the application of the corona discharge has been measured using ultraviolet and FTIR spectrophotometr

An investigation of CO2 splitting using nanosecond pulsed corona discharge: effect of argon addition on CO2 conversion and energy efficiency

The plasma chemical splitting of carbon dioxide (CO2) to produce carbon monoxide (CO) in a pulsed corona discharge was investigated from both an experimental and a numerical standpoint. High voltage nanosecond pulses were applied to a stream of pure CO2 and its mixture with argon, and the gaseous products were identified using Fourier transform infrared spectroscopy. Due to the shape of pulses, the process of CO2 splitting was found to proceed in two phases. The first phase is dominated by ionization, which generates a high electron density. Then, during the second phase, direct electron impact dissociation of CO2 contributes to a large portion of CO production. Conversion and energy efficiency were calculated for the tested conditions. The conversions achieved are comparable to those obtained using other high pressure non-thermal discharges, such as dielectric barrier discharge. However, the energy efficiencies were considerably higher, which are favorable to industrial applications that require atmospheric conditions and elevated gas flow rates

Ozone production by corona discharge using a hollow needle-plate electrode system

Ozone generation using a hollow needle-to-plate corona reactor has been investigated using both positive and negative polarities and various flow rates. Oxygen could be introduced in the reactor either through the needle electrode or through a port on the lateral wall. This configuration al-lowed studying the effect of the flow direction on ozone production

Improving the efficiency of high-temperature electrolysis of carbon dioxide in a solid oxide cell

This work focuses on the development of a bespoke rig which allows for the simultaneous use of non-thermal plasmas (NTPs), oscillating gas flow via a Desai-Zimmerman Fluidic Oscillator (DZFO) and a Solid Oxide Cell (SOC) to create a highly efficient energy conversion device to facilitate the reduction of CO2 to CO. Both fluidic oscillation and NTPs have the potential to reduce resistances in a SOC, key to furthering their commercialisation. The potential role of NTPs in improving the kinetics and efficiency of reactions relevant to CO2 reduction, such as the dissociation of CO2, is presented. Performance improvements using a rapidly oscillating gas flow, provided by the DZFO, to minimise concentration polarisation resistance by disrupting boundary layer formation and increasing overall efficiency are also discussed. The intersection of these technologies provide a path for a paradigm shift in the ability to convert waste CO2 into high value feedstock using renewable energy