| 摘要 |
<p>The crude methanol is extractively distilled in a distillation zone in which the concn. of water is at least 70%, and a fraction contng. the major portion of water (at elevated b.pt) insoluble material and other major impurities is drawn off, and a bottoms fraction, contng. aqs. methanol and the rest of the impurities is introduced into a dehydration-distillation zone, from the head of which is drawn off a fraction (I) contng. crude methanol and low b.pt. soluble and insol. impurities, and high b.pt. soluble impurities; the bottoms fraction comprises the quasi-total of the water introduced into the zone. (I) is introduced into a purification-distillation zone and the fraction (II) contng. low b.pt. impurities and bottoms fraction contng. almost all the elevated b.pt. soluble impurities are drawn off. (II) is introduced into a distillation zone and the bottoms fraction, consisting of pure methanol, drawn off.</p> |
