Aluminum carbide . It is a chemical compound that comes in the form of transparent amber-yellow crystals, its chemical formula is Al 4 C 3 and its molar mass is 143.9585 g / mol. It was discovered by Sainte Claire Deville .
Summary
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- 1 Physical properties
- 2 Nomenclature
- 3 Obtaining and applying
- 4 Sources
Physical properties
Aluminum carbide is in the form of a pale yellow or brown crystal that has a complex structural grid. It is capable of withstanding a rise in temperature to 1400 ° C at a density of 2.36 g / cm³. As part of its network of atoms of carbon they are present as discrete carbon anions.
Refers refractive indices relative to the sodium D line, and reaches 20 ° C. The Gibbs energy and the standard entropy of formation, oscillate between 196 and reach 88.95Dzh / mol / K respectively.
The preparation of this compound is possible as a by-product in complex chemical reactions, obtained by the direct reaction of carbon with aluminum in the arc furnace , where there is a smaller amount of impurities present in calcium carbide of technical origin.
It is decomposed by hot water , as well as by dilute hydrochloric acid and by concentrated sulfuric acid, releasing methane . It is used to obtain the latter compound in laboratories. Your PubChem CID: 16685054
Nomencaltura
This neutral salt acquires a certain way of being named according to the nomenclature used.
- Systematic nomenclature: tetraaluminum tricarbide
- Stock nomenclature: aluminum carbide
- Traditional nomenclature: aluminum carbide
Obtaining and applying
The production of electrolytic aluminum involves the isolation of the compound as a product of corrosion on the graphite electrodes . In the case where the aluminum carbide is reacted with water or dilute acid, methane is formed. In addition, the compound reacts with oxygen and hydrogen , and in the case of reaction with water, sodium hydroxide is concentrated forming a complex salt, called tetragidroksoalyuminatom methane and sodium .
In particular, metal matrix compounds based on aluminum matrix and reinforced with metal carbides such as boron carbide and silicon carbide , can contribute to aluminum carbide as an undesirable element. Such a situation is possible in the case of carbon fiber, which, when reacting with the aluminum matrix at temperatures above 500 ° C, also provides the target compound. During the chemical reaction step between the aluminum and the molten silicon carbide layer it can be an aluminum carbide, it will cover the silicon carbide particle and reduce the strength of the material.
This effect can be reduced by coating the appropriate silicon dioxide particles or pre-oxidation to form the silica coating. To identify at which point the water contains tritium, the compound undergoes hydrolysis , resulting in methane aluminum carbide. In this case, the compound is used as a chemical reagent in the reaction with the compound suspended with water gives tritium and methane. Aluminum carbide, dispersed in the aluminum matrix, helps preserve the density of the material, especially when combined with the silicon carbide particles.
Aluminum carbide composites can be obtained through mechanical alloys based on aluminum powder and graphite particles. Together with this compound it is used as an abrasive for high speed cutting tools, giving them a topaz hardness.
Another field of application is the pyrotechnic compound , here that allows to obtain the effect of a firefly, which results in the excessive appearance of sparks, which has been used with more or less intensity.
In general, this compound has a wide application in the chemical industry and in the production field. This is due to the chemical characteristics of aluminum carbide, providing its unique properties that are not characteristic of other types of carbide compound group.
