Syngas/H2 production from bioethanol in a continuous chemical-looping reforming prototype

• Published in: Fuel processing technology Vol. 137; pp. 24 - 30
• Main Authors: García-Labiano, F., García-Díez, E., de Diego, L.F., Serrano, A., Abad, A., Gayán, P., Adánez, J., Ruíz, J.A.C.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-09-2015
• Subjects: Bioethanol; Chemical-looping reforming; CO2 emissions; Hydrogen; Chemical-looping reforming; Bioethanol; Hydrogen; CO2 emissions
• ISSN: 0378-3820; 1873-7188
• DOI: 10.1016/j.fuproc.2015.03.022

Chemical-looping reforming (CLR) allows H2 production without CO2 emissions into the atmosphere. The use of a renewable fuel, bioethanol, in an auto-thermal CLR process has the advantage to produce H2 with negative CO2 emissions. This work presents the experimental results obtained in a continuously operating CLR unit (1kWth) using ethanol as fuel. Two NiO-based oxygen carriers were used during more than 50h of operation. The influence of variables such as temperature, water-to-fuel and oxygen-to-fuel molar ratios was analysed. Full conversion of ethanol was accomplished and carbon formation was easily avoided. A syngas composed of ≈61vol.% H2, ≈32vol.% CO, ≈5vol.% CO2 and ≈2vol.% CH4 was reached at auto-thermal conditions for both materials. Gas composition was closed to the given by the thermodynamic equilibrium. These results demonstrate the technical viability of H2/syngas production by using bioethanol in an auto-thermal CLR process.
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•Use of bioethanol in chemical-looping reforming produces H2 with low CO2 emissions.•50h of continuous operation in a 1kWth CLR unit with Ni-based oxygen carriers•Rich syngas (61% H2, 32% CO) was reached at auto-thermal conditions.•Syngas composition was close to thermodynamic equilibrium.•High purity H2 and pure N2 could be obtained in the global process.