What is acetone? The composition of this organic compound is as follows: three carbon atoms, six hydrogen atoms, one oxygen atom. Let's analyze the main physical and chemical properties of this compound, methods of preparation, and also consider the main areas of its application.
Quick reference
Acetone, the composition and properties of which we will consider in more detail, is an organic substance, the simplest representative of saturated carbonyl compounds - ketones. Translated from Latin, it means - vinegar. Previously, acetone, the composition of which has not yet been studied, was synthesized from acetates, and the finished ketone was the raw material for the production of glacial acetic acid.
It was not until the mid-nineteenth century that the German chemist Leopold Gmelin introduced the term "acetone" into the scientific lexicon.
Discovery history
Acetone, whose composition was studied only in the nineteenth century by Jeannot-Baptiste Dumas and Justus von Liebig, for the first timemanaged to open Andreas Libavius at the end of the 16th century. The substance was synthesized in the process of dry distillation of s alt - lead acetate.
Until the beginning of the twentieth century, this representative of ketones was obtained by coking wood.
During the First World War, acetone, whose composition is now known even to schoolchildren, began to be produced in other ways.
Physical properties
Acetone is a colorless mobile volatile liquid with a pungent odor. This organic compound is freely miscible with water, benzene, diethyl ether, methanol, and esters. In everyday life, almost everyone uses a solvent - acetone, the composition of which is considered as part of the course of organic chemistry.
Chemical properties
One of the most reactive ketones is acetone. The formula and properties of this organic compound are considered in terms of carbonyl compounds. In an alkaline environment, it interacts in aldol self-condensation, the reaction product is diacetone alcohol.
Under the influence of zinc, this ketone is reduced to pinacon. Pyrolysis produces ketene. Like any organic compound, acetone burns in an oxygen atmosphere to form carbon dioxide and water vapor. The process is exothermic, accompanied by the release of a significant amount of heat.
A qualitative reaction to this compound is the interaction in an alkaline medium with sodium nitroprusside. In the presence of acetone,an intense red color that turns red-violet as you add acetic acid to the solution.
The chemical composition of acetone (the presence of a double bond between the oxygen and carbon atom) explains the inability of this organic compound to enter into oxidation reactions with an ammonia solution of silver oxide and freshly prepared copper hydroxide (2).
Production of dimethyl ketone
Currently, the world produces about 6.9 million tons of acetone per year. Analysts note a steady increase in consumer demand for this ketone, as a result of which chemists are developing new options for its economical synthesis. On an industrial scale, dimethyl ketone is obtained from propene either directly or indirectly. In the cumene process, acetone is a similar synthesis product from phenol benzene. There are three stages of this production. First, benzene is alkylated with propene, and cumene is the reaction product. In the second and third stages, it is oxidized by atmospheric oxygen to hydroperoxide. In an acidic environment, this compound decomposes into acetone and phenol.
The second industrial technology for producing acetone is based on the catalytic vapor phase oxidation of isopropanol. Direct oxidation in the liquid phase of propene in the presence of a catalyst (palladium chloride) can also produce acetone.
Among the methods that are not suitable for industrial volumes due to the insignificant yield of the product, we note the fermentation of starch under the influence of bacteria.
Applications
Acetone is often used in production as a solvent. This substance perfectly degreases surfaces, dissolves chlorinated rubber, epoxy resins, polystyrene, and various organic substances. It is this ketone that is used to dissolve nitrates and cellulose.
In the pharmaceutical industry, the compound is used as the main raw material for the synthesis of methyl methacrylate, mesityl oxide, acetone cyanohydrin, acetic anhydride, diacetone alcohol.
This organic oxygen-containing compound is an excellent agent for removing grease residues from the surface. In its pure form, acetone is used to dissolve various varnishes and primers. Currently, this representative of the class of ketones is used not only as an excellent organic solvent, but also as a starting material for the industrial synthesis of polyurethanes, epoxy resins, polycarbonates, and explosive compounds. It is also necessary for the storage of acetylene, since this alkyne has an increased explosiveness, it cannot be left in its pure form. Acetylene is placed in special containers that contain a porous material impregnated with dimethyl ketone.
Among the interesting facts about the use of acetone, we note the preparation with its participation of cooling baths mixed with liquid ammonia and "dry ice".
In research laboratories, dimethyl ketone, which is the first representative of the class, is necessary for washing dirty chemical dishes. The reason for this original use of acetone is its negligibletoxicity, excellent volatility, excellent solubility in water. With the help of acetone, you can quickly dry the dishes and dry inorganic low-active compounds that do not enter into chemical interaction with it.
To purify this ketone in the laboratory, it is distilled with a small amount of potassium permanganate.
You can detect the presence of acetone in a mixture of organic compounds by interacting with solutions of furfural, sodium nitroprusside, iodine.
