Getting ammonia in industry. Getting ammonia in the laboratory

The process of producing the optimal amount of chemical substance, as well as the achievements of its maximum quality affects a number of factors. Getting ammonia depends on indicators of pressure, temperature, the presence of a catalyst used substances and method for extracting the material obtained. These parameters must be properly balanced to achieve the greatest profits from the production process.

Ammonia properties

At room temperature and normal air humidity, ammonia is in a gaseous state and has a very repulsive smell. It is endowed with poisonous and annoying mucous membranes by exposure to the body. The preparation and properties of ammonia depend on participation in the process of water, since this substance is very soluble in the normal characteristics of the environment.

Ammonia is a compound of hydrogen and nitrogen. His chemical formula is NH 3.

This chemical acts as an active reducing agent, as a result of combustion of which free nitrogen is distinguished. Ammonia shows the characteristics of the bases and alkalis.

Reaction of substance with water

When NH 3 is dissolved in water, ammonium water is obtained. Maximum at normal temperature can be dissolved in 1 volume of an aqueous element of 700 ammonia volumes. This substance is known as the ammonia alcohol and is widely used in the fertilizer production industry, in technological installations.

The NH 3 obtained by dissolving in water in terms of its qualities is partially ionized.

Naming alcohol is used in one of the methods of laboratory obtaining this item.

Obtaining a substance in the laboratory

The first method of obtaining ammonia is to bring the ammonic alcohol to a boil, after which the obtained steam dries and collect the required chemical compound. Obtaining ammonia in the laboratory is also possible by heating the harated lime and solid ammonium chloride.

The reaction of obtaining ammonia has this kind:

2NH 4 Cl + Ca (OH) 2 → CaCl 2 + 2NH 3 + 2H 2 O

During this reaction, white precipitate falls. It is salt CaCl 2, and the water and the desired ammonia are formed. To carry out the drainage of the required substance, it is passed on a mixture of lime in combination with a sir.

Getting ammonia in the laboratory does not provide the most optimal technology for its production in the required quantities. People have been looking for many years of producing substance production on industrial scales.

The origins of the production technologies

Throughout the 1775-1780, experiments were carried out on the binding of free nitrogen molecules from the atmosphere. Swedish chemist K. Shelle found a reaction that had a view

Na 2 CO 3 + 4C + N 2 \u003d 2NACN + 3CO

On its basis in 1895, N. Karo and A. Frank developed a method for binding free nitrogen molecules:

CAC 2 + N 2 \u003d CACN 2 + C

This option required high energy costs and was economically disadvantageous, so they refused it from time.

Another fairly expensive method became the open by English chemists D. Priestli and G. Cavendysh, the process of interaction of nitrogen molecules and oxygen:

Growth of the need for ammonia

In 1870, this chemical was considered an undesirable product of the gas industry and was practically useless. However, after 30 years, it became very popular in the coke-chemical industry.

At first, the increased need for ammonia was replenished by its separation from coal. But with the increase in consumption of the substance, a practical work was carried out 10 times to search for ways of its production. Getting ammonia began to be introduced using atmospheric nitrogen stocks.

The need for nitrogen-based substances was observed in almost all well-known sectors of the economy.

Search for industrial demand paths

Humanity has passed a long way to implement the production equation:

N 2 + 3H 2 \u003d 2NH 3

The production of ammonia in industry was first possible to implement in 1913 by catalytic synthesis from hydrogen and nitrogen. The method is open by F. Gaber in 1908.

Open technology allowed the long-time problem of many scientists from different countries. Up to this point, it was not possible to bind nitrogen in the form of NH 3. This chemical process was called a cyanamide reaction. With an increase in the temperature of the lime and carbon, CAC 2 (calcium carbide) was obtained. By heating nitrogen and the CACN 2 calcium cyanamide has been achieved, from which the selection of ammonia passed through hydrolysis.

Implementation of technologies to obtain ammonia

Obtaining NH 3 on the global scale of industrial consumption began with the purchase of Patent Technology F. Gaber by the representative of the Baden Social Social Plant A. Mittash. In early 1911, ammonia synthesis at a small installation became regular. K. Bosch created a large contact apparatus, based on the development of F. Gaurer. It was the original equipment that ensures the process of extraction of ammonia by synthesizing a production scale. K. Bosch took over all the guide on this issue.

Saving energy consumption suggested in the reactions of the synthesis of certain catalysts.

A group of scientists working on the search for suitable components proposed the following: the iron catalyst in which potassium and aluminum oxides were added and which is considered one of the best to obtain ammonia in industry.

09.09.1913 The world's first plant that applies catalytic synthesis technology began its work. Production capacity gradually increased, and by the end of 1917 7 thousand tons of ammonia were produced in a month. In the first year of the plant, this indicator was only 300 tons per month.

Subsequently, in all other countries, the synthesis technology was also used to apply the use of catalysts, which, in its essence, was not very different from the Gaber technique - Bosh. The use of high pressure and circulation processes occurred in any technological process.

The introduction of synthesis in Russia

Russia also used synthesis with the use of catalysts that ensure ammonia. The reaction has this kind:

In Russia, the very first ammonia synthesis plant began its work in 1928 in Chernorechensk, and then production was built in many other cities.

Practical work upon receipt of ammonia is constantly gaining momentum. In the period from 1960 to 1970, the synthesis increased almost 7 times.

In the country, mixed catalytic substances are used to successfully obtain, collect and recognize ammonia. The study of their composition is carried out by a group of scientists under the leadership of S. S. Lachinina. It is this group that found the most effective materials for the implementation of the synthesis.

The processics of the process are also constantly underway. Scientific developments in this area were M. I. Techkin, as well as his staff. In 1938, this scientist, together with his colleague V. M. Pyzhev, made an important discovery, improving the receipt of ammonia. The equation of the kinetics of the synthesis, compiled by these chemists, is from now on all over the world.

Modern synthesis process

The process of obtaining ammonia with the help of a catalyst used in today's production is reversible. Therefore, the question of the optimal level of exposure to the maximum product yield is very relevant.

The process takes place at high temperature: 400-500 ˚С. To ensure the necessary speed of the reaction, a catalyst is used. The modern production of NH 3 implies the use of high pressure - about 100-300 atm.

Together with the use of the circulation system, it is possible to obtain a sufficiently large mass of the initial materials turned into ammonia.

Modern production

The system of work of any ammonium plant is quite complicated and contains several stages. The technology of obtaining the desired substance is carried out in 6 stages. In the process of the synthesis, it is obtained, collecting and recognizing ammonia.

The initial stage consists in extracting sulfur from natural gas using the desulfurator. This manipulation is required due to the fact that the sulfur is a catalytic poison and kills the nickel catalyst at the stage of hydrogen extraction.

At the second stage, the conversion of methane passes, which proceeds with the use of high temperature and pressure when using a nickel catalyst.

In the third stage there is a partial burnout of hydrogen in air oxygen. As a result, a mixture of water vapor, carbon oxide, as well as nitrogen is produced.

At the fourth stage, a shift reaction occurs, which passes with various catalysts and two excellent temperature modes. FE 3 O 4 is originally used, and the process flows at 400 ° C. In the second stage, a copper catalyst is more effective in its influence, which allows production at low temperatures.

The next fifth stage implies the disposal of waste carbon oxide (VI) from the gas mixture by applying the absorption technology of alkali.

At the final stage of carbon (II) oxide (II) is removed using the reaction of the conversion of hydrogen into methane through a nickel catalyst and a larger temperature.

The gas mixture obtained as a result of all manipulations contains 75% hydrogen and 25% nitrogen. It is compressed under greater pressure, and then cool.

It is these manipulations that describes ammonia selection formula:

N 2 + 3H 2 ↔ 2 NH 3 + 45.9 kJ

At least this process looks not very difficult, but all of the above-mentioned actions on its implementation are talking about the complexity of obtaining ammonia on an industrial scale.

The quality of the final product is influenced by the absence of impurities in raw materials.

After passing a long way from a small laboratory experience to large-scale production, the receipt of ammonia today is in demand and indispensable industry of the chemical industry. This process is constantly improving, providing quality, efficiency and the required amount of product for each cell of the national economy.