Hydrogen production from the decomposition of ethanol aqueous solution using glow discharge plasma electrolysis

Abstract

High-energy electrons play the most important role in the decomposition of ethanol aqueous solutions under glow discharge plasma electrolysis (GDE). The non-Faradaic currents greatly improve, resulting in the actual gas production yield exceeding the theoretical yield. In this paper, we investigated a novel process of hydrogen generation from ethanol decomposition by GDE. The main gaseous products were H2 and CO; in addition to small amounts of C2H4, CH4, O2, and C2H6. The H2 volume fraction was above 59% and CO was 20%. We conclude that voltages of points C and D (VC and VD) do not change with the electrolyte concentration, but the 'Kellogg area' becomes narrower with increasing electrolyte conductivity and the glow discharge is easier to attain. In addition, with increasing ethanol volume fraction, the H2 volume fraction decreases. The maximum gas production rate occurred for ethanol volume fractions of 30% and 80%. Improving the discharge voltage and raising the electrolyte conductivity had the same effect on glow discharge plasma electrolysis as the voltage load at both ends of the plasma steam sheath increases. The H2 volume fraction remains the same upon varying the discharge voltage or electrolyte conductivity, but increasing the electrolyte conductivity is advantageous to reduce Joule heating effects caused by GDE. © Editorial office of Acta Physico-Chimica Sinica.