Conversion of methane to methanol in an ac dielectric barrier discharge

Abstract

A dielectric barrier discharge (DBD) has been used to investigate the conversion of methane to methanol and higher hydrocarbons in ac non-equilibrium plasmas. Experiments were carried out at atmospheric pressure and ambient temperature. A non-equilibrium plasma was generated in a DBD reactor by applying a high voltage to the reactor electrodes. Activation of methane molecules led to the production of C 2 hydrocarbons and methanol. The effect of the applied voltage, residence time and feed mixture such as helium and oxygen on the methane conversion and product selectivity was studied. Helium appears to have no effect on the conversion and selectivity at our applied voltages. The methane conversion increases significantly on introduction of oxygen in the feed stream. Inclusion of oxygen leads to the formation of methanol. Our results show that production of methanol is initiated around an applied voltage of 12 kV and the conversion of methane increases with increasing voltage and residence time, while the product selectivity is independent of the applied voltage.

Influence of Helium on the Conversion of Methane and Carbon dioxide in a Dielectric Barrier Discharge

“…Methane with a Rare Gas Results of mixtures of CH 4 with a rare gas have been reported [2][3][4][5]. All the results indicate a significant increase in conversion with the rare gas concentration 1 but no significant difference between helium, argon and neon.…”

Methane Conversion to C2 Hydrocarbons Using Dielectric-barrier Discharge Reactor: Effects of System Variables

“…They found the highest methanol yield of 3% and the highest methanol selectivity of 30%. Aghamir et al [12] investigated the production of the C 2 hydrocarbons and methanol by DBD. They showed that methanol formation increases with exclusion of oxygen in the feed with methane and reaching a maximum at about CH 4 /O 2 = 20, and its selectivity is independent of applied voltage after a certain value.…”

Alkane Activation at Ambient Temperatures: Unusual Selectivities, CC, CH Bond Scission versus CC Bond Coupling

“…electrons, ions and radicals) and allow operation at lower temperature as compared to catalytic processes. [8,9] In particular, methane conversion with plasma is being widely investigated using glow discharge and corona discharge. [10,11] Typically, these technologies showed, respectively, 1) gas temperatures which were higher than ambient, 2) deterioration of electrodes because of their direct contact with the plasma and 3) constriction of the plasma volume (because of the electrode's geometry).…”