| 摘要 |
<PICT:0752200/IV(a)/1> Mono-ethyl toluene is prepared by reacting toluene with ethylene at a temperature greater than 15 DEG C. but less than 90 DEG C. in the presence of aluminium chloride as a catalyst. Preferably the process is continuous at 60 DEG C. to less than 90 DEG C. In a preferred apparatus, toluene is admitted to reactor 2 by way of conduits 3 and 4 and catalyst feed tank 1 in which it becomes saturated with aluminium chloride. Ethylene gas is supplied via conduit 7 and is distributed by means of sparger 8. The products are withdrawn via conduit 10 into settling tank 11 in which the catalyst is removed. The supernatant liquid enters wash column 14 in which it is treated with caustic soda solution, the washed products passing via conduit 18 to a continuous still 19 in which toluene is removed and recovered, and may be recirculated via conduit 24. The residue passes to a second still 26 in which the required ethyl toluene is separated from the polyethyl toluenes. Catalytic activity may be increased by adding 1-5 per cent of hydrogen chloride, ethyl chloride, butyl chloride or heptyl chloride. |
