| 摘要 |
<p>Ethylene glycol (I) is recovered from mixt. with Rh-contg. tetraethylene glycol dimethyl ether (II), made by liq. phase reaction of C oxides with hydrogen in the presence of a Rh carbonyl complex catalyst and (II) as solvent, by extraction with glycerol (III). In this, the reaction mixt. is contacted with an amt. of glycerol in excess of that which is soluble in the mixt., so that two phases are formed. The (II)-phase contains most of the Rh, while the (III)-phase is rich in (I). The phases are sepd. and the (I) recovered from the (III)-phase. Pref. the extraction is carried out at low temps. esp. at room temp., at which the maximum amt. of (II) which can be dissolved in (III) gives a soln. contg. 0.78 wt.% (II) Low boiling components such as water, (m)ethanol and methyl formate are pref. removed before the extraction, e.g. by a mild distillation. The extraction process is simpler than prior art distillation procedures, and gives reduced losses of the Rh catalyst.</p> |
