초록 |
Ni-Mg-Al mixed oxides catalysts have been prepared by coprecipitation, ion-exchange and impregnation method using Mg-Al layered double hydroxides(LDHs) as the precursors and was used as selective catalysts for hydrogenation of 1,3-butadiene. The precursors based on [Mg1-x2+ Alx3+{OH}2]x+ (CO3-)x mH2O were prepared with various of Mg/Al ratios. The catalysts were characterized using several methods such as x-ray diffraction, elemental analysis, BET, and TPD. In the matrix of the catalysts, the positions of NiO (sub-lattice, interface and outer surface) were determined for various catalysts, and it was found that the position strongly affected the catalytic performances. Moreover, it was found that catalytic properties such as activity, selectivity, and stability were affected by not only amounts of Ni loading but also oxidation state of Ni in the matrix of the catalysts. |