Preparation of benzene from ethanol and acetylene

Benzene can be prepared by acetylene gas. When acetylene gas send through a heated pipe, benzene is be given as a one of the product. Before that we have to convert ethanol to acetylene.


ethanol to benzene conversion steps

We know, first we have to prepare acetylene from ethanol. Each steps of converting ethanol to benzene and acetylene (ethyne) to benzene is explaned below.


Ethanol to ethene

Ethanol reacts with concentrated sulfuric acid and heated to happen the reaction. Ethene (C2H4) is given as the product.


Ethene to dibromoethane

Liquid bromine is added to ethene. Br2 is dissolved in CCl4. Two bromine atoms are added through double bond and dibromoethane is given as the product. Dibromoethane is an alkyl halide compound.

Bromoethane - BrCH2CH2Br


Dibromoethane to ethyne | acetylene

Alkyl halides are treated and heated with alcoholic KOH to give alkenes or alkynes. When dibromoethane is treated and heated with alcoholic KOH, ethyne (acetylene) is given. Acetylene is an alkyne.

Acetylene / ethyne / C2H2


preparation of benzene from acetylene

Ethyne (acetylene) is sent through a heated copper pipe. Cu is behaved as a catalyst. Acetylene polymerizes and give benzene as one product. In this reaction, aromatic compound is prepared by an aliphatic compound.




ethanol to benzene

Ethanol to benzene through acetylene


Ethanol and benzene

  • Both ethanol and benzene are liquids at room temperature.
  • Benzene is very toxic comparing with ethanol.
  • Ethanol reacts with Na, but benzene does not react with Na.


What are the other ways of preparing acetylene from ethanol

Ethene is prepared from ethanol as below reactions. Then ethene reacts with basic KMnO4. It gives diol compound (HO-CH2-CH2-OH). Then it is heated with concentrated H2SO4 to get acetylene.



How to prepare benzene from phenol and acetylene

We have already discussed the acetylene to benzene conversion.


From phenol

When phenol is distilled with zinc dust, it gives benzene.



More Organic Conversions