Partial oxidation of ethanol using a non-equilibrium plasma

Partial oxidation of ethanol with air was carried out in a pulsed discharge plasma reactor at low temperature and atmospheric pressure. Effects of O2:ethanol ratio, ethanol flow rate, and discharge current were investigated. H2 and CO are the major products (>86%). Increases of O2:ethanol ratio promote CO formation at the expense of C2 hydrocarbons. H2 selectivity and H2 + CO selectivity are maximized at O2:ethanol ratios of 0.3 and 0.5, respectively. Increases of feed flow rate accompanied by current increases allow the reactor to operate with high throughput. The LHV energy efficiency is increased with increasing feed flow rate, reaching 85% at high ethanol flow rates, conditions that also increase throughput. In contrast to catalytic and homogenous reactions, not all O2 is consumed at high O2:ethanol ratio for the low temperature plasma reaction. A radical reaction pathway of H abstraction from –OH and the α-H in ethanol to form CH3CHO followed by C–C scission is proposed. The produced hydrogen rich gas can be potentially used in fuel cells and engines.