Cu-Co bi-metal catalysts derived from CuO/LaCoO3 perovskite structure were prepared by one-step citrate complexing method, and the structure evolution reaction from CuO/LaCoO3 to Cu-Co2C/La202CO3 under 1-12 pretreatme...Cu-Co bi-metal catalysts derived from CuO/LaCoO3 perovskite structure were prepared by one-step citrate complexing method, and the structure evolution reaction from CuO/LaCoO3 to Cu-Co2C/La202CO3 under 1-12 pretreatment was investigated by techniques of XRD, TPR and TEM. The results suggest that a much higher dispersion of copper significantly enhanced the reduction of cobalt, and a stronger interaction between copper and cobalt ions in LaCoO3 particles led to the formation of bi-metallic Cu-Co particles in the reduced catalysts and the enrichment of Co on the surface of bimetallic particles. The prepared catalysts were highly active and selective for the alcohol synthesis from syngas due to the presence of copper-modified C02C species.展开更多
LaFeO3 perovskite supported Ni and Ni-Fe catalysts were prepared and applied to methanation reaction of syngas. Two preparation methods were employed. One was one-step citrate complexing method, and the other was a tw...LaFeO3 perovskite supported Ni and Ni-Fe catalysts were prepared and applied to methanation reaction of syngas. Two preparation methods were employed. One was one-step citrate complexing method, and the other was a two step method using citrate complexing method to produce LaFeO3 and followed by loading nickel oxide on it with impregnation. The structure evolution of the sample as prepared was investigated by XRD, TPR and TEM techniques. For the former, the chemical composites of the calcined sample are NiO-Fe2O3/LaFe1-xNixO3. After reduction and reaction of CO methanation, its composites convert to Fe-Ni@Ni/LaFeO3-La2O2CO3, in which Fe-Ni@Ni is metal particles in nano-size composed of nickel core and Fe-Ni alloy shell. For the latter, the chemical composites of the calcined sample are NiO/LaFeO3; and after reduction and reaction of CO methanation, its chemical composites change to Ni/LaFeO3. Ni/LaFeO3 catalyst is a little more active, while Fe-Ni@Ni/LaFeO3-La2O2CO3 is much more stable and shows very good resistance to carbon deposition. In this work it is aimed to show that the structure and composites of the catalysts can be tailored using perovskite-type oxide as precursor with different preparing method or preparing condition. Therefore, it is a promising route to prepare supported bi-metal catalysts in nano-size for a lot of metals with desired catalytic performances.展开更多
Series of meso-macroporous Al2O3 supported Ru catalysts with different loadings were prepared by incipient wetness method and applied to preferential oxidation of CO in hydrogen-rich gases. N2 adsorption-desorption, S...Series of meso-macroporous Al2O3 supported Ru catalysts with different loadings were prepared by incipient wetness method and applied to preferential oxidation of CO in hydrogen-rich gases. N2 adsorption-desorption, SEM, XRD, TEM, CO chemisorption and H2-TPR techniques were employed to characterize the catalysts. The results indicate that Ru/Al2O3 catalysts have meso-macroporous structure, high surface area and high metal dispersion. The characterization results of XRD and CO chemisorption indicate the entry of Ru ions into Al2O3 lattice. The results of catalytic performance tests indicate that the meso-macroporous Al2O3 supported Ru catalysts for CO preferential oxidation showed good activity under high space velocity. It is proposed that the macropores in the Ru/Al2O3 catalyst favor mass transfer and mesopores help to improve the dispersion of metal, resulting in the excellent catalytic performance.展开更多
基金supported by the Program for Scientific Research Innovation Team in Colleges and Universities of Shandong Provincethe Ph.D.Programs Foundation of Liaocheng University(No.31805)the NSF of China(21263011,21376170)
文摘Cu-Co bi-metal catalysts derived from CuO/LaCoO3 perovskite structure were prepared by one-step citrate complexing method, and the structure evolution reaction from CuO/LaCoO3 to Cu-Co2C/La202CO3 under 1-12 pretreatment was investigated by techniques of XRD, TPR and TEM. The results suggest that a much higher dispersion of copper significantly enhanced the reduction of cobalt, and a stronger interaction between copper and cobalt ions in LaCoO3 particles led to the formation of bi-metallic Cu-Co particles in the reduced catalysts and the enrichment of Co on the surface of bimetallic particles. The prepared catalysts were highly active and selective for the alcohol synthesis from syngas due to the presence of copper-modified C02C species.
基金supported by the Financial support from the NSF of China(21066007)the NSF of Tianjin China(10JCZDJC23800)the NSF of Mongolia China(2009BS0203)
文摘LaFeO3 perovskite supported Ni and Ni-Fe catalysts were prepared and applied to methanation reaction of syngas. Two preparation methods were employed. One was one-step citrate complexing method, and the other was a two step method using citrate complexing method to produce LaFeO3 and followed by loading nickel oxide on it with impregnation. The structure evolution of the sample as prepared was investigated by XRD, TPR and TEM techniques. For the former, the chemical composites of the calcined sample are NiO-Fe2O3/LaFe1-xNixO3. After reduction and reaction of CO methanation, its composites convert to Fe-Ni@Ni/LaFeO3-La2O2CO3, in which Fe-Ni@Ni is metal particles in nano-size composed of nickel core and Fe-Ni alloy shell. For the latter, the chemical composites of the calcined sample are NiO/LaFeO3; and after reduction and reaction of CO methanation, its chemical composites change to Ni/LaFeO3. Ni/LaFeO3 catalyst is a little more active, while Fe-Ni@Ni/LaFeO3-La2O2CO3 is much more stable and shows very good resistance to carbon deposition. In this work it is aimed to show that the structure and composites of the catalysts can be tailored using perovskite-type oxide as precursor with different preparing method or preparing condition. Therefore, it is a promising route to prepare supported bi-metal catalysts in nano-size for a lot of metals with desired catalytic performances.
基金supported by the NSFC(No.20976121)the NSF of Tianjin of China(10JCZDJC23800)the Doctoral Fund of Ministry of Education of China(20100032110019)
文摘Series of meso-macroporous Al2O3 supported Ru catalysts with different loadings were prepared by incipient wetness method and applied to preferential oxidation of CO in hydrogen-rich gases. N2 adsorption-desorption, SEM, XRD, TEM, CO chemisorption and H2-TPR techniques were employed to characterize the catalysts. The results indicate that Ru/Al2O3 catalysts have meso-macroporous structure, high surface area and high metal dispersion. The characterization results of XRD and CO chemisorption indicate the entry of Ru ions into Al2O3 lattice. The results of catalytic performance tests indicate that the meso-macroporous Al2O3 supported Ru catalysts for CO preferential oxidation showed good activity under high space velocity. It is proposed that the macropores in the Ru/Al2O3 catalyst favor mass transfer and mesopores help to improve the dispersion of metal, resulting in the excellent catalytic performance.
