PROCESS FOR THE PURIFICATION OF ETHYLENE GLYCOL

The present invention is directed to a process for the purification of ethylene glycol from a crude stream thereof. The process comprises passing the stream of crude ethylene glycol to a first distillation column in which light compounds within the crude stream are separated overhead and a lights-removed crude ethylene glycol stream is removed from at or near the bottom of the first distillation column; passing the lights-removed crude ethylene glycol stream removed from at or near the bottom of the first distillation column to a second distillation column in which purified ethylene glycol is separated and recovered from heavy components present in the lights-removed crude ethylene glycol stream; removing a stream from at or near the bottom of the second distillation column which comprises residual ethylene glycol together with diethylene glycol and heavy compounds and passing said stream to a third distillation column in which the heavy compounds are separated from the stream comprising ethylene glycol and diethylene glycol; and removing the stream comprising ethylene glycol and diethylene glycol from the third distillation column and passing said stream to a fourth distillation column in which the ethylene glycol is separated from the diethylene glycol.