High Efficiency Gas-to-Liquids through Condensation of Small Hydrocarbons Using Corona Discharge Processes

The conversion of small hydrocarbons to longer ones that are liquids at room temperature is the general focus of gas to liquid (GTL) technologies. Recently, the co-authors have been investigating the direct GTL conversion through direct condensation of short hydrocarbons to longer ones using low energy corona discharges.

In this process, low energy electron impact ionization through the use of a non-thermal plasma generated by an atmospheric pressure electric corona discharge is used to generate reactive radicals in the gas phase that subsequently recombine to produce the longer hydrocarbons. By implementing this approach in a microchemical reactor we can take advantage of strong electric field gradients and efficient heat and energy management resulting in the stabilization of the corona discharge in a very non-thermal plasma regime.

Both single-discharge and multi-discharge reactors have been built, and their performance demonstrates the chemical conversion concept presented. A brief investigation of important process parameters shows that the power level per discharge, the discharge gap, and the reactive gas flow rate is particularly important. A high energy efficiency of up to 85% (electrical to chemical energy) can be achieved, and methane conversion can reach up to 25% with high selectivity (80~90%) towards C2+ hydrocarbons.