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Abstract. This study deals with paracetamol degradation in water using a non-thermal plasma (NTP) created by a dielectric barrier discharge (DBD). The effects of the NTP operating conditions on the degradation were studied, showing that the treatment efficiency of the process was highly dependent on the electrical parameters and working gas composition in the reactor containing the aqueous solution. A conversion rate higher than 99% was reached with an energy yield of 12 g/kWh. High resolution mass spectrometry (HRMS) measurements showed that the main species produced in water during the process were nitrogen compounds, carboxylic acids and aromatic compounds.

In this paper we present the fabrication technology used to make micro-discharge ‘reactors’ on a silicon (Si) substrate. For the fabrication of these reactors we have used Si wafers with 4 inch diameter and standard cleanroom facilities. The fabrication technology used is compatible with standard CMOS device fabrication and the fabricated micro-discharge reactors can be used to produce dc discharges. These micro-discharges operate at near atmospheric pressure. They were given ring-shaped anodes separated from the cathode by a SiO2 dielectric with a thickness of approximately 5–6 µm rather than the much more common ∼100 µm. The micro-discharge reactors can consist of either a single hole or multiple holes and we have built devices with holes from 25 to 150 µm in diameter. The micro-discharge measurements were obtained for helium and argon dc plasmas between 100 and 1000 Torr. We used a single ballast resistor to produce micro-discharges in multi-hole array. This resistor also acted to limit the discharge power. An average current density of 0.8 A cm−2 was calculated for the 1024 holes array with 100 µm diameter holes. In addition, we will report on stability of micro-discharges depending on the cavity configuration of the micro-reactors and the ignition trends for the micro-discharge arrays. Finally, we discuss the life time of micro-discharge arrays as well as the factors affecting them (cathode sputtering, thermally affected zones, etc).