In order to obtain acetylene from methane, it is necessary to carry out a dehydrogenation reaction. Before proceeding to its consideration, let's analyze some features of the hydrocarbon.
Acetylene characteristic
This is a gaseous substance, which is the first representative of the class of unsaturated hydrocarbons (alkynes). It is lighter than air and poorly soluble in water. The molecular formula C2H2, common to the entire class SpN2p-2. Acetylene is considered to be an active chemical and highly explosive. In order to avoid emergencies, it is stored in sealed steel containers with charcoal added to it.
Production from alkanes
Acetylene was obtained from the decomposition of methane. This chemical reaction is carried out using a catalyst and occurs at an elevated temperature. The starting material is the first representative of the class of paraffins. Dehydrogenation produces hydrogen in addition to acetylene.
Answering the question of how to get acetylene from methane, the reaction equation can be represented as:
2CH4=C2H2+3H2
Carbide method
It is possible to obtain acetylene from methane or asstarting material to take calcium carbide. The process proceeds under normal conditions. When calcium carbide interacts with water, not only acetylene is formed, but also calcium hydroxide (slaked lime). Signs of a chemical process will be gas evolution (hissing), as well as a change in color of the solution when adding phenolphthalein to a raspberry color.
When technical carbide containing various impurities is used as a starting material, an unpleasant odor is observed during the interaction. It is explained by the presence in the reaction products of such toxic gaseous substances as phosphine, hydrogen sulfide.
Cracking of petroleum products
At present, it is possible to obtain acetylene not only from methane. The main industrial method for the production of this representative of alkynes is the cracking (splitting) of hydrocarbons. If acetylene is obtained from methane, then energy costs will be minimal. In addition to inexpensive and accessible raw materials, this technology attracts producers of hydrocarbon raw materials by the simplicity of the technological equipment used in the process of methane dehydrogenation.
There are two options for such a chemical process. The first method is based on passing methane through electrodes heated to 1600 degrees Celsius. The technology involves a sharp cooling of the resulting product. The second option for the dehydrogenation of methane to produce acetylene involves the use of energy that is generated during the partial combustion of this alkyne.
Cylinders containing acetylene cannot be equipped with bronze valves, as bronze contains copper. The interaction of this metal with acetylene is accompanied by the formation of an explosive s alt.
Conclusion
Acetylene is currently used in various industrial areas. It is a valuable raw material for the synthesis of ethanol, plastics, rubbers, and acetic acid. This representative of the alkyne class is in demand when cutting and welding metals, as a bright light in individual lamps.
On the basis of acetylene, the synthesis of explosives used as detonators is carried out. In the oxidation reaction of this alkyne in atmospheric oxygen, a strong flame is observed. Methane is of no less value in the chemical industry. In addition to its use as a starting material for the production of acetylene, it is consumed in large quantities as a natural hydrocarbon in the fuel industry. When it burns, a significant amount of heat is released.
