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

Abstract

We have studied the production of synthesis gas and other hydrocarbons in a dielectric barrier discharge using mixtures of helium, methane and carbon dioxide. It was found that helium has a significant influence on the discharge, decreasing the breakdown voltage and increasing the rate of conversion of CH 4 and CO 2 . However it also decreases the selectivities and the range of stable operating conditions for the discharge. The main products obtained were H 2 , CO, C 2 H 6 and C 3 H 8 but traces of other hydrocarbon, carbon deposition and the formation of condensable products were also detected. The rate of conversion and conversion abilities were obtained by fitting the conversion results to a model.

Influence of gas expansion on process parameters in non-thermal plasma plug-flow reactors: A study applied to dry reforming of methane

“…In order to test the sensitivity of the method, we choose mixtures with helium concentrations of (85, 80 and 75)%. Previous results [17] have shown that with these concentrations, the products of the rate of conversion and concentration for each reactant, show a maximum. The carbon, oxygen and hydrogen balance, calculated from Equation (16) neglecting condensation, were b C ¼ 1.00 (2), b O ¼ 0.99 (2) and b H ¼0.95 (2).…”

“…[17]. In order to test the sensitivity of the method, we choose mixtures with helium concentrations of (85, 80 and 75)%.…”

“…This was the case in our first attempt to address the effect of gas expansion. We studied the mixtures He/CH 4 /CO 2 and He/CH 4 /O 2 and were able to obtain an accurate value forã based on the He concentration [17]. In these measurements, however, the concentration of helium was indirectly obtained from the concentration of all other gases, leading to a low precision of the final value.…”

“…A variation of the latter is when a component itself of the feed gas is used as internal standard. We have used this variation of the technique to obtain the expansion ratio a discussed below, in a previous study [17].…”

“…From the cited authors, only three show expressions for process parameters based on fluxes [15,13] or on the concentrations and a correction factor [17].…”