File:Air-free sublimation.png

Air-free_sublimation.png (800 × 475像素,文件大小:31 KB,MIME类型:image/png


摘要

描述

Air-free sublimation

Apparatus

a = Rubber cone (typically used to form a vacuum seal in a Büchner flask filtration) which is selected so as to fit snugly around the neck of the Schlenk tube

b = Schlenk tube

c = Gas/vacuum inlet

d = Teflon tap (or stopcock)

e = Syringe

Method steps

1 = Impure solid to sublime (brown) is placed in a Schlenk tube, avoiding contaminating the sides of the tube (e.g. by careful evaporation from a solution containing the brown solid).

2 = Rubber cone (black) is pushed near top of the Schlenk tube (forming a tight seal around flask) and filled with a coolant such as dry ice/acetone (blue/white) to cool the neck of the Schlenk tube. The bottom of the Schlenk tube is heated (red shading) under vacuum (blue arrow), so that the impure solid (brown) sublimes as a pure solid (purple) at the cooled neck area (blue shading).

3 = After sublimation, the cooling-cone (black) is removed, leaving the concentrated impurity as a residue (dark brown) in the bottom of the flask, and the purified sublimed solid (purple) at the neck of the Schlenk tube.

4 = Solvent (blue) is inserted via syringe to dissolve the residue (green/brown), taking care to avoid washing off the sublimed solid (purple).

5 = Residue solution is then removed by syringe (green/brown) (Steps 4 and 5 can be repeated as required).

6 = Purified sublimed solid (purple) is washed off the neck of the flask with fresh solvent (blue) via a syringe.

(In steps 3 to 6 the flask is held under an atmosphere of an inert gas via Schlenk tube side arm).

7 = Solvent is removed under vacuum to give the purified sublimed solid (dark purple).

Steps 6 and 7 are not essential
来源 自己的作品
作者 Quantockgoblin

许可协议

Public domain 我,本作品著作权人,释出本作品至公有领域。这适用于全世界。
在一些国家这可能不合法;如果是这样的话,那么:
我无条件地授予任何人以任何目的使用本作品的权利,除非这些条件是法律规定所必需的。

说明

添加一行文字以描述该文件所表现的内容

此文件中描述的项目

描繪內容

某些值没有维基数据项目

7b184d742322502d2f07f9b201c688389359e48e

31,351 字节

475 像素

800 像素

文件历史

点击某个日期/时间查看对应时刻的文件。

日期/时间缩⁠略⁠图大小用户备注
当前2008年3月13日 (四) 23:402008年3月13日 (四) 23:40版本的缩略图800 × 475(31 KB)Quantockgoblin~commonswiki{{Information |Description=air-free sublimation a b c d e f g 1 2 3 4 5 6 7 8 |Source=self-made |Date= |Author= Quantockgoblin |Permission= |other_versions= }}

以下页面使用本文件:

全域文件用途

以下其他wiki使用此文件: