Ziegler型触媒による綿実油の低温水素添加

抄録

The homogeneous hydrogenation of cottonseed oil in n-hexane by using a binary catalyst system of Ziegler type, nickel acetylacetonate (Ni (acac) ₂) and triethylaluminium (Et₃Al), was performed at low temperatures down to -20°C where saturated or less soluble glycerides crystallized out of the reacting solution. Although so low temperature hydrogenation was somewhat difficult because of the lower reaction temperature and consequent less catalyst activity, authours have successfully made it as follows :
1) For 50g of refined cottonseed oil and 160g of n-hexane solution, an Al/Ni ratio 6 catalyst was used which containing Ni (acac) ₂ 0.23×10^-2mole and Et₃Al 1.46×10^-2mole.
2) The temperature of the reaction mixture was held at 20°C for the first 5 minutes of the reaction (prereduction treatment), then was cooled to a certain temperature as rapid as possible, thereafter the reaction was carried out at that definite temperature.
3) Hydrogen gas was introduced in at the rate of 500ml/min under atmospheric pressure.