Boosting hydrogen production from steam reforming of ethanol on nickel by lanthanum doped ceria

• Published in: Applied catalysis. B, Environmental Vol. 286; p. 119884
• Main Authors: Xiao, Zhourong, Wu, Chan, Wang, Li, Xu, Jisheng, Zheng, Qiancheng, Pan, Lun, Zou, Jijun, Zhang, Xiangwen, Li, Guozhu
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.06.2021; Elsevier BV
• Subjects: Catalysts; Cerium oxides; Coke; Ethanol; Ethanol steam reforming; Hydrogen; Hydrogen production; La doped ceria; Lanthanum; Metal-support interaction; Metals; Nanoparticles; Nickel; Oxygen; Reforming; Sol-gel processes; Steam; Vacancies; Zirconium; Metal-support interaction; La doped ceria; Ethanol steam reforming; Hydrogen production
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2021.119884

Designing and developing catalysts with high resistance to coke deposition and metal sintering in steam reforming of ethanol (SRE) for stable hydrogen production has always drawn great attention. In this work, ceria supported Ni catalysts have been doped by a third metal (La, Tb, and Zr) using a sol-gel method. Detailed characterization and investigation regarding the application of ceria supported Ni catalysts in SRE has been carried out. The size and dispersion of Ni nanoparticles, surface oxygen vacancies and metal-supported interaction have been finely tuned. Moreover, DFT + U calculations were conducted to reveal the mechanism of oxygen-vacancy formation and water dissociation on the catalysts. Complete conversion of ethanol with high H2 product rate have been stablely maintained for more than 3000 min over Ni-CeLa0.2 under high GHSV and low H2O/C ratio. [Display omitted] •Metal (La, Tb, Zr)-doped CeO2 supported Ni catalysts are prepared by a simple citric acid assisted sol-gel method.•The origin of oxygen vacancy and the mechanism for water dissociation are revealed by DFT calculations.•Highly active and stable ethanol reforming is achieved under high GHSV and low H2O/C ratio at 600 °C.•Coking and Ni sintering are effectively suppressed by the sol-gel doping of La into ceria supported Ni. Stable and efficient hydrogen production has always been the focus of industry, and steam reforming of ethanol (SRE) is one of the most robust, renewable and cheap technologies. To develop excellent SRE catalysts highly resisting coke formation and metal sintering, La, Tb, and Zr have been doped as a third metal into Ni-CeO2 catalyst using a sol-gel method. The size and dispersion of Ni nanoparticles, surface oxygen vacancies and metal-supported interaction have been finely tuned, with which the catalytic performance is closely associated. La-doped ceria supported Ni (Ni-CeLa0.20) exhibited superior catalytic performance, which is ascribed to its large Ni active surface area, abundant oxygen vacancies and suitable metal-supported interaction. DFT calculations showed that the doping of La into Ni-CeO2 can promote the generation of oxygen vacancies and facilitate the dissociation of water. On Ni-CeLa0.20, complete conversion of ethanol and stable hydrogen production have been maintained in the 3000-min test. The coke deposition is only 0.48 mgc/gcat h at 600 °C under the GHSV of 55920 mL/gcat∙h.