Safety specification for anhydrous and oxygen-free operation

Some compounds are very sensitive to water or oxygen or even nitrogen in the air.

In order to ensure that such compounds are not interfered by water and oxygen, special instruments and anhydrous and oxygen-free operation techniques must be used in the process of synthesis, separation, purification or analysis and identification

1.

For systems with less stringent requirements, a method of directly passing inert gas into the reaction system to replace the air can be used.

Second, the glove box

Sampling, weighing, grinding, etc.

There are simple glove boxes, such as those with plexiglass shells, and complex ones, such as buffer chambers, such as stainless steel shells (except for glass windows)

The glove box with a stainless steel shell is more expensive and consists of long neoprene gloves, an exhaust port, an air intake port and a well-sealed glass window

Advantages of the glove box: anhydrous and oxygen-free effect is good

Disadvantages of the glove box: inconvenient operation and unfavorable cable; all utensils and chemicals must be put in in advance, once forgotten, they need to restart, delaying the process or seriously affecting the results

3.

The Shrank line is also called an anhydrous and oxygen-free operating line, which is a set of inert gas purification and operating systems

Figure 23-17 is a schematic diagram of the Shrank line structure

Figure 23-17 Schematic diagram of the Shrank Line structure

Since commercially available inert gases generally contain oxygen and 10-50 ppm moisture, a purification treatment system is required

For the usual anhydrous and oxygen-free operation, it can be simplified according to actual needs, and generally only double-row pipes are required

Advantages: anhydrous and oxygen-free effect is good, and it is more convenient to use than a glove box

Disadvantages: complicated preparatory work

Suggestion: The double-row tube is relatively simple, and its application in general chemical laboratories can be widely promoted
.