In industry, obtaining caprolactam from benzene is considered the most promising method. Let us consider in more detail the features of this production, as well as the main characteristics of the resulting compound.
Synthesis features
In the technological chain there is the hydrogenation of benzene to cycloalkane (with a platinum or nickel-chromium catalyst, temperature 220°C). The cyclohexane formed during the oxidation is converted into cyclohexanone at 0.9-1.1 MPa, 140-160°C. Further, by dehydrogenation on chromium-zinc catalysts (in the presence of alkali), it is converted into oxime. At the last stage, cyclohexanone oxime is treated with oleum or concentrated sulfuric acid, turning it into caprolactam (synthesis temperature - 60-120 ° C).
Process Features
In what percentage is caprolactam obtained by the described method? In fact,the product yield is 66-68 percent. That is why other production technologies have been developed. In particular, photochemical synthesis, in which 86-88% is released by photochemical nitrosation of cyclohexane to caprolactam under the influence of UV irradiation.
In the chemical industry, caprolactam is also produced from toluene, oxidizing it at 165°C (on a platinum catalyst), followed by nitrosation of the resulting carboxylic acid cyclohexane into crude caprolactam.
What is caprolactam obtained by one of the methods listed above? In fact, it is a solid substance in which there are impurities. First, it must be cleaned of them using ion-exchange resins, then distilled. A by-product of this production is ammonium sulfate, a valuable mineral fertilizer.
Solid caprolactam is transported in paper multilayer bags, and the liquid product is transported in special tanks with additional heating. Currently, this component is obtained mainly from benzene, phenol, toluene.
Basic Features
What makes caprolactam different? The properties of this heterocyclic compound deserve separate consideration. It is a white crystalline substance with good solubility in water, ether, alcohol, benzene. Heating it in the presence of amines, alcohol and water leads to the polymerization of caprolactam into a polyamide resin. It is this substance that is the basis for the manufacture of the polymer. So, it is caprolactam that acts as a monomer for the process. What is polymerization? This term refers to the process of obtaining a product from a monomer - nylon.
Applications
What is the main purpose of the production in question? Why is caprolactam produced in the chemical industry? Its application is quite diverse. It is necessary for polyamide films, engineering plates. In minimal volumes, it is used in the synthesis of lysine and polyurethane. Why is caprolactam so popular? What it is? This organic compound is used in the synthesis of solvents for paints, as well as in the creation of synthetic leather, plasticizers.
Consumption by industry
In which modern industries is caprolactam needed? What is it - kapron? These questions are considered within the framework of the school course of organic chemistry. There is a demand for these products in the automotive industry. But despite this, its maximum volumes are used for the manufacture of polyamide fibers and threads, as well as for the manufacture of modern engineering plastics (about 60% - for fibers and threads, about 34% - for the manufacture of engineering plastics). The remaining raw materials are used in the creation of packaging materials, various products for the sanitary sector.
Polyamide fibers are needed for the manufacture of textiles, industrial yarns, carpets. It is this product that is becoming increasingly popular in the polymer materials market.
Important points
Pub resin is also in demand in the manufacture of engineering plastics. She is a componentfor the production of elements of electrical and electronic equipment, as well as automotive parts. Oriented polyamide film is a material that is widely used in the packaging industry. Caprolactam is also used in its manufacture.
What is lysine? Let's dwell on this substance in a little more detail. Lysine is an amino acid that a person needs for the normal functioning of the body. The lack of this substance leads to a violation of the human immune system, which negatively affects the he alth of the body as a whole. The chemical synthesis of lysine from caprolactam through several successive stages is a technology that allows solving the problem of deficiency of this substance. The use of innovative technologies makes it possible to speed up the process and reduce its cost.
Summarize
Among those products that can be obtained from caprolactam, polyamide fibers and resins are of particular interest. In particular, capron has also received the maximum prevalence at the present time. This polymer is indispensable in many industrial areas. It is used in mechanical engineering, surgical medicine, chemical production, instrument making. It is from nylon that high-quality lines for modern parachutes, ropes, ropes, various fishing tackle, strings for musical instruments, clothes, and toys are made.
A huge number of polymeric materials obtained from caprolactam explain the demand for this material in the world market. Yes, strengthkapron threads are ten times more than silk, 50 times more than viscose. For the production of polymers, only high-quality raw materials are used.
That is why special attention in the modern chemical industry is paid to the preliminary purification of caprolactam from additional impurities (dust, moisture). Otherwise, it is difficult to count on getting the desired quality capron.
Over the past decade, the production of plastics and synthetic resins has increased significantly. There are new materials created on the basis of caprolactam. The demand for these compounds in mechanical engineering and construction is also growing.
