ISSN 1063-7842, Technical Physics, 2013, Vol. 58, No. 8, pp. 1138–1143. © Pleiades Publishing, Ltd., 2013. Original Russian Text © A.N. Tsymbalyuk, D.S. Levko, V.Ya. Chernyak, E.V. Martysh, O.A. Nedybalyuk, E.V. Solomenko, 2013, published in Zhurnal Tekhnicheskoi Fiziki, 2013, Vol. 83, No. 8, pp. 53–58. 1138 INTRODUCTION Synthesis gas (mixture of carbon monoxide CO and molecular hydrogen H 2 ) is an important interme- diate product in synthesis of different chemical sub- stances, such as ammonia, methanol, gasoline, diesel fuel, etc. [1]. The synthesis of different substances requires different ratios [H 2 ]/[CO]. There are several techniques for synthesis gas pro- duction: processing of a solid fossil fuel by overheated steam, partial oxidation of natural gas, thermal decomposition of wood material, and conversion of different hydrocarbon fuels in the plasmas of different discharges [2]. Today, natural gas (methane) is the main source of synthesis gas [1]. However, the supplies of natural gas are running short; therefore, the search for alternative sources that could provide a high yield of synthesis gas with a controllable [H 2 ]/[CO] ratio are underway. It was suggested [3] that plasma conversion of ethanol C 2 H 5 OH be used instead of vapor conver- sion of methane in the production of synthesis gas. The fact is that ethanol is a renewable fuel that can be obtained from biomass or industrial waste. Here, a tor- nado reactor is supposed to serve as a reactor where ethanol will be converted [4–7]. In such a reactor, the state of the electrical discharge plasma is found in between nonequilibrium and equilibrium states. On the one hand, this is because the mean energy of elec- trons in this plasma is still about 1–2 eV and their dis- tribution function remains nonequilibrium. This allows one to selectively excite different degrees of freedom of the gas and also effectively dissociate mol- ecules by electron impact. On the other hand, the gas temperature in such a plasma may reach 1000–1500 K due to the energy release in the chemical transforma- tions of ethanol and hydrocarbons produced in plasma-chemical reactions. The high temperature of the gas mixture makes it possible to increase the H 2 concentration through the conversion of hydrocar- bons forming in the discharge. Additionally, since the temperature of the gas mixture remains high after the discharge is quenched, the conversion is effective in the post-discharge region as well. The production of synthesis gas from pure ethanol in the electrical discharge plasma suffers from a con- siderable disadvantage: it is impossible to control the [H 2 ]/[CO] ratio in the mixture. Therefore, conversion of an ethanol–CO 2 mixture is suggested. From the stoichiometric equation C 2 H 5 OH + CO 2 3H 2 + 3CO (ΔH = 297.31 kJ/mol) it follows that CO 2 added to the mixture makes it pos- sible to decrease the ethanol consumption twofold, since it contains carbon atoms. In addition, varying the initial C 2 H 5 OH/CO 2 concentration ratio, one can obtain synthesis gas with different final [H 2 ]/[CO] ratios. In this work, we study (both experimentally and by numerical simulation) the influence of the discharge parameters, gas mixture temperature, and rate of the CO 2 flow through the discharge on the composition of synthesis gas at the exit from the reactor in which an Influence of the Gas Mixture Temperature on the Efficiency of Synthesis Gas Production from Ethanol in a Nonequilibrium Plasma A. N. Tsymbalyuk a , D. S. Levko b *, V. Ya. Chernyak c , E. V. Martysh c , O. A. Nedybalyuk c , and E. V. Solomenko c a V. Dal’ East Ukrainian National University, Molodezhnyi bul. 20a, Lugansk, 93034 Ukraine b Israel Institute of Technology, Technion, Haifa, 32000 Israel c Shevchenko National University, pr. Akademika Glushkova 2/5, Kyiv, 03122 Ukraine *e-mail: dima.levko@gmail.com Received November 21, 2912 Abstract—The mechanism behind the plasma conversion of a mixture of ethanol vapor, water vapor, air, and carbon dioxide CO 2 in the nonequilibrium plasma of a tornado discharge is studied. The influence of the CO 2 flow rate, the current through the discharge, and the gas temperature in the discharge on the concentrations of molecular hydrogen and carbon monoxide CO is studied. Comparison between the concentrations of the gas- eous mixture’s main components at the output from the reactor obtained experimentally and by numerical sim- ulation shows that the adopted kinetic mechanism adequately describes the plasma kinetics in the mixture. DOI: 10.1134/S1063784213080252 PLASMA