In the field of chemistry there are many types of hydrocarbons among which are the alkynes , which are characterized by the presence of a triple bond of carbon-carbon . One of the most important alkynes is acetylene , which is also the simplest of all, a type of gas that is slightly more colorless and lighter than air.
The acetylene , also known by the name ethene , is the simplest and best known member of hydrocarbons which comprises one or more pairs of carbon atoms which are connected by triple bonds are known as acetylenic series or alkynes
- Acetylene Characteristics
- What is acetylene for
- Environmental impact
- Advantages of acetylene
There are several characteristics that can be found in acetylene, among the most important we can find the following:
- This compound is characterized by having a low polarity .
- They are insoluble in water but at the same time they are soluble in organic solvents.
- Their triple bonds give them a great capacity for chemical reactivity .
- When in normal conditions, it is a gas that is characterized by being more lightweight than air .
- It has no color .
- It has no odor , but when used commercially , it has a garlic- like odor .
- It is not corrosive nor is it toxic .
- You can burn with ease before a luminous flame or high temperatures.
- When subjected to high pressure it becomes quite unstable .
- It has a boiling point of -57 ° C and a melting point of -81 ° C.
- Its vapor pressure is 4460 kPa when it is at 20 ° C.
- Its relative density is 0.907
Acetylene was first discovered by Edmund Davy in the year 1836 when he was isolating the potassium by the heating of carbonate of potassium with carbon . Although he was able to see the potential of the new hydrocarbon by the luminosity of its flame, this finding was not well recognized and gradually fell into oblivion. It was thanks to Marcellin Berthelot , a French organic chemist who is considered one of the pioneers of thermochemistry , that he managed to rediscover the compound by giving it the name of acetylene., around the year 1860 .
The composition of acetylene is based on carbon (7.74%) and hydrogen (92.96%) and its chemical formula is as follows:
What is acetylene for
Acetylene’s primary use is in metal cutting and welding when it burns with oxygen. In ancient times it was also used as a medium for lighting and today it is also an important part of the chemical industry. It is also used in the process of texturing, cutting profiles, marking wooden pallets and in carbon coverings. It is also used in organic synthesis in laboratory work and in chemical synthesis .
The gas is also used in the glass industry and materials processing , which often use it for carbon cladding . This is because acetylene helps create lubrication between the surfaces of the material. Furthermore, acetylene is the only fuel gas used to weld various types of stainless steels .
In order to obtain acetylene should cause a reaction of the water with the carbide of calcium , it gains a gas release rate volatile having the ability to produce high temperatures . In the field of petrochemicals, it can be obtained by means of a technique known as quenching, which means rapid cooling. This technique uses a flame of natural gas or various volatile fractions of oil together with oils that have a high boiling point .
It can be obtained by means of a hydrolysis reaction caused in calcium carbide , in this reaction, when the carbons that are bound with calcium, are saturated with the two hydrogens and then a displacement reaction occurs where they are forms a hydroxide in relation to water. So, the carbons break the bond with calcium and then join together to create a triple bond , calcium ends with two free valences and then join two hydroxides in a single bond .
The environmental impact produced by acetylene occurs when it works as a fuel and when it comes into contact with the ozone layer, causing significant damage to it. In addition, when it comes into contact with the environment, it turns out to be harmful to health as it acts as a type of suffocating gas and at high concentrations it can also become a powerful narcotic . When inhaled at very high concentrations it can even cause death within a few minutes.
Its main derivatives are:
- Acetylene formaldehyde
- Butadiene used to make synthetic rubber.
Advantages of acetylene
Among the main advantages of acetylene are the following:
- It is inexpensive .
- Can be used to harden , heat , bend or forge materials
- It is used in practically any type of welding .
- It is not a toxic gas for humans or animals.
- The low moisture content of this gas makes it perfect for various industrial processes that require critical heating.
- It is one of the hottest combustible gases , producing a flame temperature of about 3,150 ° C when combined with oxygen.
Acetylene also has some important disadvantages, among which we can mention the following:
- Acetylene has the ability to explode if compressed , liquefied , mixed with air, or heated.
- Acetylene becomes very unstable when it is above 25 psi pressure, which makes it also explosive.
- The method of production of acetylene, its storage , its load or its use can be dangerous if not handled properly. For this reason, gas production plants and cylinder loading are regulated by standards, rules and codes.
Acetylene turns out to be an important gas because it is the commercially most important alkyne and is often used as a type of fuel for torches .