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This paper presents the results of a theoretical and experimental study of plasma-assisted reforming of ethanol into molecular hydrogen in a new modification of the "tornado" type electrical discharge.Numerical modeling clarifies the nature of the non-thermal conversion and explains the kinetic mechanism of nonequilibrium plasma-chemical transformations in the gas-liquid system and the evolution of hydrogen during the reforming as a function of discharge parameters and ethanol-to-water ratio in the mixture. We also propose a scheme of chemical reactions for plasma kinetics description. It is shown that some characteristics of the investigated reactor are at least not inferior to characteristics of other plasma chemical reactors. PACS: 52.65.-y, 52.80.-s IntroductionThe interest to alternative fuels research in the last two decades is increased by the depletion of the traditional fossil fuels. Today, ethanol is considered the most perspective fuel for internal-combustion engines [1]. First, it could be produced from renewable sources (biomass, industrial waste, etc). Second, its combustion produces relatively small amount of pollutants. However, the low velocity of the ethanol combustion wave propagation does not allow its use in its pure form as an engine fuel [2]. In order to increase this velocity, one needs to enrich С 2 Н 5 ОН by molecular hydrogen [3], since the latter has higher flame speed than alcohol. Unfortunately, there is another problem of storing H 2 on a vehicle. Recently, several methods were proposed to obtain hydrogen from hydrocarbon fuels before its entering to the engine [1]. The methods are partial oxidation, steam reforming, dry CO 2 reforming, thermal decomposition and plasma-assisted reforming.The use of non-equilibrium plasma looks more attractive as a result of its lower energy consumption. Plasma acts as a catalyst and initiates fast chain reactions that do not progress under normal conditions. Today different plasma chemical reactors are used (for example [1], [4][5][6]) for molecular hydrogen generation from different hydrocarbons (ethanol, methane, etc) in non-equilibrium plasma. In [7][8], a new plasma chemical reactor for ethanol-to-hydrogen conversion was proposed. It was shown

This work presents the results of theoretical and experimental studies on the effect of air humidity on the kinetics of plasma-chemical processes in a plasma-chemical reactor consisting of 16 volume barrier discharges and an 80 L volume working chamber. The component content of active species both in the discharge gap and in the working chamber was calculated under the conditions of the use of dry (RH = 20%) and wet (RH = 80%) ambient air, a specific discharge power of 1.5 W cm −3 , a temperature of the gas medium in the discharge of 300-500 K and various residence times of the species in the discharge volume. The calculations were performed for the steady-state effective electric field in the discharge gap equal to 20 kV cm −1 . It is found that, in spite of the difference between the rotational temperatures of nitrogen molecules in discharges in dry and wet air (≈400 K and ≈440 K, respectively), the best agreement between the calculations and the experiments for both the RH values is observed for the same calculated temperature of the gas medium in the discharge (≈425 K). In most cases, the calculated concentrations of O 3 , HNO 3 , HNO 2 , N 2 O 5 and NO 3 in the discharge gap and in the working chamber are in fairly good agreement with the respective measured data.