| Popis: |
Y-Mg-Al-LDO is successfully prepared by coprecipitation method and heat treatment. The catalytic performance of Y-Mg-Al-LDO is evaluated in the preparation of isophorone by condensation of acetone. The results shows that the Y-Mg-Al-LDO catalyst has higher activity under the reactive conditions of 300 °C and 6 mL·h-1 charging air speed so as to the conversion of acetone improved 17.8 % and the selectivity of isophorone increased 11.0 %. The products were characterized by XRD, FT-IR, CO2-TPD and BET. The results indicated that the basicity, the number of strong base center and pore volume and pore size of Y-Mg-Al-LDO were increased. Large ion Y3+ softened hydrotalcite porous structure, but did not change its layered crystal structure. The crystallinity of hydrotalcite was affected due to the amount of doped Y3+. Y2O3 was highly dispersed when small amount of Y3+ was doped, and laminates were distorted because of some of Y3+ was risen out of the scope of Mg2+ in the lattice when a large amount of Y3+ was doped. |
