| 摘要 |
<p>The present invention is a process for producing substantially anhydrous ethanol of very high purity by azeotropically distilling aqueous ethanol with cyclohexane as an entrainer in a drying still, removing substantially all the water as an overhead fraction as a ternary azeotrope of water/cyclohexane/ethanol, and withdrawing anhydrous ethanol in the vapour phase either from the lower half of the drying still or as an overhead fraction from a further tailing still into which anhydrous liquid ethanol from the base of the drying still has been fed. This method prevents ethanol from being down-graded with respect to its permanganate time and Komarowski values owing to solvent extraction of impurities from flexible materials used for jointing purposes and pump seals. The final product is of very high purity and may be used in potable or pharmaceutical applications.</p> |
