ZrO_2-modified Ni/LaAl_(11)O_(18) catalyst for CO methanation: Effects of catalyst structure on catalytic performance

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.

A solvent-free,selective liquid phase hydrogenation of nitroarenes to aniline in slurry bubble mode on porous NiMo bimetallic catalyst

NiMo bimetallic catalysts were prepared by a solid reaction method.On the NiMo catalyst,the selective liquid phase hydrogenation of nitrobenzene to aniline was achieved in slurry bubble mode.And the high yields(98.9%)were obtained under the conditions of 80℃,solvent-free and atmospheric pressure.The effect of Mo on the catalytic behavior of Ni based catalyst was investigated.The characterization displayed that the inclusion of Mo could improve the specific surface area and pore volume,and the solid reaction method made metal Mo enrichment on the surface of catalyst.These two aspects should be responsible for excellent catalytic performance of NiMo catalyst.In sum,we described a simple and efficient NiMo catalyst and provided a facile and green procedure for liquid phase hydrogenation of nitrobenzene to aniline.