The film provides a detailed analysis of nitration processes using a nitrating mixture, obtaining nitro compounds, cleaning them from excess acids and preparing them for further processing. The film material is recommended as a teaching aid for vocational school students.
Explosion.
Without stabilizers based on nitro compounds, car tires would soon be destroyed.
People walking around VDNKh.
Without dyes based on nitro compounds, fabrics could not be dyed.
Reproductions using printing dyes based on nitro compounds.
Processing film for movies with materials based on the products of the nitration process.
Samples of film for photography.
A cartoon explaining the nitration process.
Samples of nitro compounds.
Properties and structure of nitro compounds.
An experiment on carrying out a nitration reaction.
Nitric acid is introduced into a flask with benzene.
The nitration reaction is exothermic, it is accompanied by the release of heat.
Over time, the reaction slows down, and more and more brown vapors, nitrogen oxides, accumulate in the flask.
A cartoon explaining this process.
To ensure the nitration process, it is necessary to bind water, since water slows down the nitration process.
Concentrated sulfuric acid - oleum - is used for this.
Therefore, a mixture of sulfuric and nitric acids is used as a nitrating agent.
Heat is also released during the preparation of the nitrating mixture.
Experiment on conducting a nitration reaction using a nitrating mixture.
Nitric acid of various concentrations is used to prepare the nitrating mixture.
Nitric acid of different densities.
An example of an accurate measurement of the density of nitric acid.
To obtain mononitro derivatives, nitric acid is introduced into the reaction in an amount close to the theoretical one.
If 500 g of benzene is nitrated with a certain amount of nitric acid, we will obtain mononitrobenzene.
To obtain polynitrobenzene, an excess amount of nitric acid is needed.
Containers with oleum, copperas oil and monohydrate.
The more nitro groups must be introduced into the molecule of the aromatic compound, the higher the concentration of sulfuric acid must be.
Special mixers for preparing the nitrating mixture.
A cartoon explaining the process of preparing the nitrating mixture.
The temperature of the reaction mass during the nitration process must be regulated.
Strong overheating can lead to the accumulation of gases, the release of mass or even an explosion.
Nitration, Nitrating mixture
In order to maintain the reaction temperature within the specified limits, it is necessary to regulate the feed rate of the nitrating mixture and cooling.
These processes are demonstrated in a laboratory experiment.
In production conditions, these problems are solved thanks to the special design of the reaction apparatus - the nitrator.
Cartoon showing the operation of such an apparatus.
The nitrator is monitored automatically.
Cartoon showing the design of the monitoring and control devices.
Cartoon showing the action of the feedback of the control devices with the technological process inside the nitrator.
The automatic system also operates when the mixer stops or its speed slows down.
If the degree of cooling is insufficient, the operator increases the feed of water or brine.
The operator monitors the readings.
To obtain each individual nitration product, the appropriate process conditions are selected.
Formula for obtaining mononitrobenzene and the composition of the nitrating mixture.
Formula for nitration of toluene and chlorobenzene with a similar composition of the nitrating mixture.
During nitration of the last two elements, mixtures of different isomers are formed.
Reaction formulas.
Formula for nitration of naphthalene.
Samples of the obtained nitro compounds.
They must be isolated from the reaction mass.
If the nitro compound is liquid, it is usually insoluble in the spent acid.
It is isolated by simple settling.
If the insoluble reaction product is solid but low-melting, it is separated from the spent acid by melting.
By pouring the melt into cold water, the product can be granulated.
If the compound is soluble in water, it is often transferred for further processing without preliminary isolation.
Cartoon showing the nitration of naphthalene trisulfonic acid from sulfonated naphthalene.
Cartoon explaining the process of removing excess nitric acid.
The nitro mass in the form of a solution is transferred for further processing.
Nitration