| 초록 |
NiO supported on zirconia modified with MoO3 for acid catalysis was prepared by drying powdered Ni(OH)2-Zr(OH)4 with ammonium heptamolybdate aqueous solution, followed by calcining in air at high temperature. The characterization of prepared catalysts was performed using FTIR, Raman, XRD, and DSC. MoO3 equal to or less than 15 wt% was dispersed on the surface of catalyst as two-dimensional polymolybdate or monomolybdate, while for MoO3 above 15 wt%, crystalline orthorhombic phase of MoO3 was formed, showing that the critical dispersion capacity of MoO3 on the surface of catalyst is 0.18 g/g NiO-ZrO2 on the basis of XRD analysis. Acidity and catalytic activities for acid catalysis increased with the amount of dispersed MoO3. The high acid strength and acidity was responsible for the Mo=O bond nature of the complex formed by the interaction between MoO3 and ZrO2. The catalytic activity for acid catalysis was correlated with the acidity of the catalysts measured by the ammonia chemisorption method. |
