Regular Article

Hydrogen production by conversion of ethanol injected into a microwave plasma^★

¹ Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231 Gdańsk, Poland
² Department of Marine Electronics, Gdynia Maritime University, Morska 81-87, 81-225 Gdynia, Poland

^a e-mail: dczylkowski@imp.gda.pl

Received: 31 August 2017
Received in final form: 17 October 2017
Published online: 12 December 2017

Abstract

Reforming of gaseous and liquid hydrocarbon compounds into hydrogen is of high interest. In this paper we present a microwave (2.45 GHz) plasma-based method for hydrogen production by conversion of ethanol (C₂H₅OH) in the thermal reforming process in nitrogen plasma. In contrast to our earlier investigations, in which C₂H₅OH vapour was supplied into the microwave plasma region either in the form of a swirl or axial flow, in this experiment we injected C₂H₅OH vapour directly into the nitrogen microwave plasma flame, behind the microwave plasma generation region. The experimental results were as follows. At an absorbed microwave power of 5 kW, N₂ (plasma-generating gas) swirl flow rate of 2700 NL(N₂)/h and C₂H₅OH mass flow rate of 2.7 kg(C₂H₅OH)/h the hydrogen production rate was 1016 NL(H₂)/h, which corresponds to the energy yield of hydrogen production 203 NL(H₂)/kWh. After the C₂H₅OH conversion the outlet gas contained 27.6% (vol.) H₂, 10.2% CO, 0.2% CO₂, 4.8% CH₄, 4.3% C₂H₂, 3.7% C₂H₄ and 3.7% C₂H₆. These results are comparable to those obtained in our earlier investigations, in which different methods of C₂H₅OH vapour supply to the microwave plasma generation region were employed.