| 摘要 |
<PICT:0836792/IV (b)/1> Aluminium is heated with an aluminium tri alkyl and hydrogen at a pressure higher than 20 atmospheres to produce a dialkyl aluminium hydride. The aluminium is preferably in finely-divided form, such as atomized aluminium formed by spraying molten aluminium by means of an inert gas into liquid aluminium trialkyl in an inert solvent such as hexane or benzene. The aluminium may also be activated by mechanical comminution or by corrosion with a dialkyl aluminium monohalide. The reaction product may be further treated with an olefin to give an aluminium trialkyl, either as a separate step or by forcing the olefin under pressure into the reactor in which the dialkyl aluminium hydride is formed. The process may be conducted in the apparatus shown in the drawing. Molten aluminium is sprayed from a supply vessel 1 into a chamber 2 containing a, say, 5% solution of aluminium triethyl. The suspension is allowed to settle in vessel 5, the solvent being returned to chamber 2 via line 4 and the thick suspension being pumped to reaction tower I via pump 7 and line 8. Hydrogen is supplied via line 9 and any extra aluminium triethyl required via line 11. The reaction product passes to a separator 13, hydrogen being removed at 14 and recycled, and diethyl aluminium hydride passing via line 15 to reactor II where it is reacted with ethylene introduced via line 16. The product mixture is separated in distillation column 18, ethylene being recycled via line 19, solvent returned to the atomization chamber 2 via line 3, and the residual aluminium triethyl being extracted via line 20, a measured proportion being conveyed to tower I via pipe 21. Specification 770,707 is referred to. |
