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.

In this work the electron kinetics in He/CH 4 /CO 2 mixtures used for CH 4 conversion is studied, including the contribution of H 2 and CO formed in the discharge, as an initial step to model the reforming of natural gas for syngas production in a dielectric barrier discharge. The electron Boltzmann equation for a swarm in the hydrodynamic regime is solved in mixtures of He/CH 4 /CO 2 /CO/H 2 . The method used takes into account nonconservative terms and the full angular dependency of the electron velocity distribution function (evdf). The role of He and the effect of the change in composition by conversion of reagents into products in the evdf, transport parameters, reaction rates, and power losses are discussed and quantified.