Sorption enhanced ethanol steam reforming on a bifunctional Ni/CaO catalyst for H-2 production

[EN]The activity and stability of a 10 wt%NiO/CaO catalyst were tested in the sorption enhanced ethanol steam reforming (SEESR) in a fluidized bed reactor. The effect of temperature in the 600-750 degrees C range was analyzed and the performance of the catalyst at 700 degrees C was assessed by conducting cycles of SEESR reaction and CO2 desorption. At zero time on stream, an increase in temperature enhanced ethanol steam reforming reactions, and therefore H-2 production increased from a yield of 20.3 wt% at 600 degrees C to 22 wt% at 750 degrees C. However, high temperatures hindered the catalyst sorption performance, i.e., CO2 capture declined from 7.9 to 2.1 mmol(CO2) g(cat)(-1). In order to evaluate the catalyst performance throughout the cycles and relate it with its features, both fresh and deactivated catalysts were characterized in detail by N-2 adsorption-desorption, X-ray fluorescence (XRF), X-ray diffraction (XRD), temperature programmed reduction (TPR) and oxidation (TPO) and transmission electron microscopy (TEM). Subsequent to 12 cycles, the catalyst CO2 capture performance was slightly lower than that of the fresh one (approximately 7%) and hardly changed in the next cycles. Furthermore, the use of the same temperature for SEESR reaction and CO2 desorption led to the highest adsorption capacity of the catalyst over multiple cycles.This work was carried out with financial support from the Spain's Ministries of Science, Innovation and Universities (RTI2018-098283-J-I00 (MCIU/AEI/FEDER, UE) and (RTI2018-101678-BI00 MCIU/AEI/FEDER, UE) and Science and Innovation (PID2019-107357RB-I00 (MCI/AEI/FEDER, UE) , the Basque Government (IT1218-19 and KK-2020/00107) . This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 823745. Maria Cortazar also thanks the Basque Government for her research training grant