Characterization of the activity and stability of supported cobalt catalysts for the steam reforming of ethanol

• Published in: Journal of power sources 2003-10, Vol.124 (1), p.99-103
• Main Authors: Batista, Marcelo S, Santos, Rudye K.S, Assaf, Elisabete M, Assaf, José M, Ticianelli, Edson A
• Format: Article
• Language: English
• Subjects: Applied sciences; Cobalt catalyst; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Ethanol; Exact sciences and technology; Fuel cell; Fuel cells; Hydrogen production; Steam reforming
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/S0378-7753(03)00599-8

This paper reports results of studies of the catalytic activity and stability of supported cobalt catalysts for steam reforming of ethanol. Co/Al 2O 3, Co/SiO 2, and Co/MgO catalysts were prepared by an impregnation method and characterized by X-ray diffraction, atomic absorption spectroscopy, Raman spectroscopy, and temperature programmed reduction with hydrogen. The results showed the presence of Co 3O 4 and CoO x species interacting with Al 2O 3 or MgO and formed after a calcination step. It was evident that only Co 0 sites are active for the steam reforming of ethanol. All materials showed high levels of ethanol conversion, with molar yields of about 70% of hydrogen and 30% of CO+CO 2+CH 4 in the gaseous mixture. The Co/Al 2O 3 catalyst also produced ethylene through a dehydration reaction of ethanol. It is proposed that the methane formation on Co/SiO 2 catalysts occurs by methanation of CO and by ethanol decomposition. After 9 h of reaction, 14–24% (w/w) of carbon was deposited on all catalysts, indicating that a well characterized deactivation of the materials is due to coke deposition.