异丙醇除水！？ 摘自: Purification of Laboratory Chemicals Isopropanol (propan-2-ol) [67-63-0] M 60.1, b 8 2 . 5o, d 4 20 0.783, n25.8 1.3739, pK25 1 7 . 1 . Isopropyl alcohol is prepared commercially by dissolution of propene in H2SO4, followed by hydrolysis of the sulfate ester. Major impurities are water, lower alcohols and oxidation products such as aldehydes and ketones. Purification of isopropanol follows substantially the same procedure as for n-propyl alcohol. Isopropanol forms a constant-boiling mixture, b 80.3o, with water. Most of the water can be removed from this 91% isopropanol by refluxing with CaO (200g/L) for several hours, then distilling. The distillate can be dried further with CaH2, magnesium ribbon, BaO, CaSO4, calcium, anhydrous CuSO4 or Linde type 5A molecular sieves. Distillation from sulfanilic acid removes ammonia and other basic impurities. Peroxides [indicated by liberation of iodine from weakly acid (HCl) solutions of 2% KI] can be removed by refluxing with solid stannous chloride or with NaBH4 then the alcohol is fractionally distilled. To obtain isopropanol containing only 0.002M of water, sodium (8g/L) is dissolved in material dried by distillation from CaSO4. Isopropyl benzoate (35mL) is then added and, after refluxing for 3hours, the alcohol is distilled through a 50-cm Vigreux column (p 11). [Hine & Tanabe J Am Chem Soc 80 3002 1958.] Other purification steps for isopropanol include refluxing with solid aluminium isopropoxide, refluxing with NaBH4 for 24hours, and removing acetone by treatment with, and distillation from, 2,4-dinitrophenylhydrazine. Peroxides re-form in isopropanol if it is kept for several days in contact with air. [Beilstein 1 IV 1461.]查看更多
求助 以下报错分别代表什么意思? warning in the "properties" paragraph which begins on line 52 free-water method should be steamnbs when the main property method is srk. default free-water method is steam-ta please specify the recommended free-water method and run again. （注：新人不了解物性方法的选择，看到网上有一篇相关的精馏模拟使用pro ii ,采用的物性方法是srkm，故选择了srk。。。其实我不知道这两者到底是不是一回事 t t【见笑】） 、 warning in the "stream" paragraph which begins on line 68 stream name: 00 component mass flows of substream: "mixed" are normalized to the total mass flow value. （注：这条报错看到的很多，mixed的物流被标准化为全质量流量值，具体是指什么意思呢？） 本人第一次接触过aspen软件，属于一头雾水、到处乱撞的小白。目前的状态就是“按照原设计图纸把流程画好”，“输入已知数据”，“nnnnnnn"，"运行"，"报错"，"找错误"这样一个流程，连盖德论坛也是google错误内容时偶尔发现的……希望盖德论坛的大侠能鞭策我直到猛醒为止！orz，小白跪拜！ 查看更多
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