NiMo catalysts supported on TNT(x) were prepared by incipient
wetness co-impregnation of aqueous solutions of precursor salts:
nickel nitrate, Ni(NO3)26H2O (Aldrich), and ammonium heptamolybdate,
(NH4)6Mo7O244H2O (Merck). The pH of the impregnation
solutions used was adjusted to 9 using NH4OH. Citric acid,
C6H8O7H2O (Aldrich), was added to the impregnation solutions
to stabilize them and avoid precipitation of Ni(OH)2. After impregnation,
the catalysts were dried (100 C, 6 h) and calcined in air
(350 C, 2 h). The nominal composition of the catalysts was
8 104 mol/g of MoO3 (12 wt.%) and 4 104 mol/g of NiO
(3 wt.%). Hereafter, the catalysts will be denoted as NiMo/TNT(x).
For comparison purposes, three NiMo catalysts supported on commercial
anatase nanopowder (TiO2-NP, 144 m2/g, Aldrich) were
also prepared. One of these catalysts was supported on anatase
nanopowder, while two other catalysts were supported on
TiO2-NP materials previously modified with different amounts of
sodium. For this purpose, anatase nanopowder was first impregnated
with the required amount of NaOH dissolved in water, dried
(100 C, 12 h) and calcined (350 C, 2 h). Then Na-containing
TiO2-NP supports were used for the preparation of the NiMo catalysts
with the same Mo and Ni loadings, and following the same
catalyst preparation procedure as described above. Catalysts from this series will be denoted as NiMo/TiO2-NP(y), where y represents
Na loading (wt.%) in the support. Ni and Mo content of the calcined
oxide catalysts was analyzed by SEM–EDX using a JEOL 5900 LV
microscope with OXFORD ISIS equipment. For all prepared catalysts,
determined MoO3 content varied between 11.9 and
12.2 wt.%, whereas NiO loading was between 2.9 and 3.1 wt.%,
which is in good agreement with the expected nominal composition
of the catalysts.
NiMo catalysts supported on TNT(x) were prepared by incipientwetness co-impregnation of aqueous solutions of precursor salts:nickel nitrate, Ni(NO3)26H2O (Aldrich), and ammonium heptamolybdate,(NH4)6Mo7O244H2O (Merck). The pH of the impregnationsolutions used was adjusted to 9 using NH4OH. Citric acid,C6H8O7H2O (Aldrich), was added to the impregnation solutionsto stabilize them and avoid precipitation of Ni(OH)2. After impregnation,the catalysts were dried (100 C, 6 h) and calcined in air(350 C, 2 h). The nominal composition of the catalysts was8 104 mol/g of MoO3 (12 wt.%) and 4 104 mol/g of NiO(3 wt.%). Hereafter, the catalysts will be denoted as NiMo/TNT(x).For comparison purposes, three NiMo catalysts supported on commercialanatase nanopowder (TiO2-NP, 144 m2/g, Aldrich) werealso prepared. One of these catalysts was supported on anatasenanopowder, while two other catalysts were supported onTiO2-NP materials previously modified with different amounts ofsodium. For this purpose, anatase nanopowder was first impregnatedwith the required amount of NaOH dissolved in water, dried(100 C, 12 h) and calcined (350 C, 2 h). Then Na-containingTiO2-NP supports were used for the preparation of the NiMo catalystswith the same Mo and Ni loadings, and following the samecatalyst preparation procedure as described above. Catalysts from this series will be denoted as NiMo/TiO2-NP(y), where y representsNa loading (wt.%) in the support. Ni and Mo content of the calcinedoxide catalysts was analyzed by SEM–EDX using a JEOL 5900 LVmicroscope with OXFORD ISIS equipment. For all prepared catalysts,determined MoO3 content varied between 11.9 and12.2 wt.%, whereas NiO loading was between 2.9 and 3.1 wt.%,which is in good agreement with the expected nominal compositionof the catalysts.
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