Microwave plasma torches driven by surface wave applied for hydrogen production

A microwave (2.45 GHz) Ar plasma torch at atmospheric pressure has been applied for hydrogen production from the decomposition of alcohols (methanol and ethanol). The hydrogen yield dependence on the gas fluxes and the microwave input power has been investigated both in Ar and Ar + water plasma environments. Mass and FTIR spectroscopy have been used to detect the molecular hydrogen produced and the H2O, CO2 and CO molecules in the exhaust gas stream. Nearly 100% decomposition of methanol molecules was achieved in the Ar plasma torch. It was further found that the H2 yield increases significantly when water is added into the Ar/methanol/ethanol mixtures. Moreover, optical emission spectroscopy has been applied to determine the gas temperature, the electron density and the radiative species present in the plasma torch. The results clearly show that this device provides an efficient plasma environment for hydrogen production.