通过共沉淀法制备铈锆固溶体作为载体,采用等体积、分步浸渍的方法制备了一系列10%Ni-3%La/Ce x Zr1-x O2(x=0、0.16、0.5、0.75、1)催化剂,并将其应用到甲烷部分氧化和甲烷二氧化碳重整耦合制合成气的反应中.对不同Ce/Zr比的催化剂性...通过共沉淀法制备铈锆固溶体作为载体,采用等体积、分步浸渍的方法制备了一系列10%Ni-3%La/Ce x Zr1-x O2(x=0、0.16、0.5、0.75、1)催化剂,并将其应用到甲烷部分氧化和甲烷二氧化碳重整耦合制合成气的反应中.对不同Ce/Zr比的催化剂性能展开研究,采用BET、XRD、H2-TPR、SEM、TG-DSC手段对载体及催化剂进行了表征.结果表明,铈锆固溶体的形成不仅提高了催化剂表面活性组分的分散度,使催化剂表面NiO晶粒尺寸从26.5 nm减到13.7 nm;而且能够加强活性组分与载体之间的相互作用,提高催化剂的热稳定性能;随着Ce/Zr比的增加,催化剂的转化率、选择性及稳定性随之增高,其顺序为:Ni-La/Ce0.75Zr0.25O2>Ni-La/Ce0.5Zr0.5O2>NiLa/Ce0.16Zr0.84O2.展开更多
We report Ni/LaHA@ZrO2catalysts prepared by a facile modified successive adsorption and reaction method for CO methanation.N2adsorption,X‐ray diffraction,transmission electron microscopy,scanning electron microscopy,...We report Ni/LaHA@ZrO2catalysts prepared by a facile modified successive adsorption and reaction method for CO methanation.N2adsorption,X‐ray diffraction,transmission electron microscopy,scanning electron microscopy,thermogravimetric analysis,H2temperature‐programmed reduction,H2temperature‐programmed desorption,X‐ray photoelectron spectroscopy,thermogravimetric analysis,and inductively coupled plasma atomic emission spectrometry were used to characterize the samples.The results indicated that the ZrO2nanoparticles were distributed over the surface of the Ni/LaHA@ZrO2catalyst and even partially covered some Ni particles,resulting in the coating exerting a confinement effect.The excess ZrO2had an adverse effect on the enhancement of CO conversion because of the coverage of the surface Ni particles;however,the Ni/LaHA@ZrO2catalyst displayed much higher CH4selectivity than Ni/LaHA because of the activation of the byproduct CO2molecules by ZrO2species.Therefore,even though20Ni/LaHA@ZrO2‐5exhibited similar CO conversion as20Ni/LaHA,the use of the former resulted in a higher CH4yield than the use of the latter.A107‐h‐lifetime test revealed that the Ni/LaHA@ZrO2catalyst was highly stable with superior anti‐sintering and anti‐coking properties because of its coating structure and the promoter effect of ZrO2.展开更多
基金supported by the National Natural Science Foundation of China (21606146)Natural Science Foundation of Shandong Province (ZR2016BB17,2016ZRB01037)+3 种基金Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents (2016RCJJ005,2016RCJJ006)Government Sponsored Visiting Scholar Foundation of Shandong University of Science and Technology (2016)Qingdao Postdoctoral Applied Research Project (2015202)China National Coal Association Science and Technology Research Program (MTKJ2016-266)~~
文摘We report Ni/LaHA@ZrO2catalysts prepared by a facile modified successive adsorption and reaction method for CO methanation.N2adsorption,X‐ray diffraction,transmission electron microscopy,scanning electron microscopy,thermogravimetric analysis,H2temperature‐programmed reduction,H2temperature‐programmed desorption,X‐ray photoelectron spectroscopy,thermogravimetric analysis,and inductively coupled plasma atomic emission spectrometry were used to characterize the samples.The results indicated that the ZrO2nanoparticles were distributed over the surface of the Ni/LaHA@ZrO2catalyst and even partially covered some Ni particles,resulting in the coating exerting a confinement effect.The excess ZrO2had an adverse effect on the enhancement of CO conversion because of the coverage of the surface Ni particles;however,the Ni/LaHA@ZrO2catalyst displayed much higher CH4selectivity than Ni/LaHA because of the activation of the byproduct CO2molecules by ZrO2species.Therefore,even though20Ni/LaHA@ZrO2‐5exhibited similar CO conversion as20Ni/LaHA,the use of the former resulted in a higher CH4yield than the use of the latter.A107‐h‐lifetime test revealed that the Ni/LaHA@ZrO2catalyst was highly stable with superior anti‐sintering and anti‐coking properties because of its coating structure and the promoter effect of ZrO2.