Propene . Also called Propylene , it is an alkene formed by three atoms of carbon and 6 atoms hydrogen , global formula C 3 H 6 . It is a homolog of ethylene , it presents the double bond as a functional group.
Summary
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- 1 Physical and chemical properties
- 2 Obtaining
- 3 Applications
- 4 Reactions
- 1 Hydrohalogenation
- 2 Halogenation
- 3 Addition of sulfuric acid
- 4 hydroformylation
- 5 Polymerization
- 6 Ozonolysis with reductive cleavage
- 7 Oxidative cleavage
- 5 Sources
Physical and chemical properties
- Molecular mass: 42.1 g / mol
- Melting point: –185.3 ° C
- Boiling point: –48 ° C
- Ignition temperature: 460 ° C
- Vapor pressure at 20 ° C: 10,200 hPa
- Maximum concentration allowed in the workplace: 500 ppm
- Explosive limits: 2.0 – 11.1% propene in air.
Obtaining
contituye one of the products of thermolysis of the oil . It is separated from other products such as ethylene by distillation at low temperature.
Applications
- In the synthesis of polypropylene.
- The addition of water under polar conditions gives iso-propanolthat can be oxidized to acetone .
- The addition of water under conditions radicalconditions n-propanol is obtained .
Reactions
Hydrohalogenation
Hydrohalogenation occurs by bubbling a hydrogen halide into a container containing propene in ether . As the main product of the reaction, 2-halogenpropane will be obtained . Example: using HBr, 2-bromopropane is obtained ).
Halogenation
A reacting the propene with makes a halogen in carbon tetrachloride as the solvent produced 1.2-dihalógenopropano Example: using I 2 is obtained the 1,2-diiodopropane .
Adding sulfuric acid
The sulfuric acid concentrate is added to propene mechanism for electrophilic addition producing acid isopropyl sulfate .
hydroformylation
The hydroformylation of propene with carbon monoxide , water and catalyst of cobalt at high pressures and temperatures produce butanal as main product.
Polymerization
The polymerization of propylene to polypropylene can be carried out on a radical basis, although in the catalytic polymerization products with better qualities are obtained, which are also better controllable. The catalysts used were originally of the Ziegler-Natta type . They are currently being replaced by other zirconocene- based systems .
Ozonolysis with reductive cleavage
By Ozonolysis with subsequent oxidative cleavage you are obtained as product formaldehyde and acetaldehyde .
Oxidative cleavage
Violent oxidation of propene with hot KMnO 4 results from oxidative cleavage , acetic acid , and carbon dioxide . The same products would also be obtained by ozonolysis with ozone (O 3 ) at low temperatures (-78 ° C) and subsequent oxidative cleavage with hydrogen peroxide (H 2 O 2 ) in alkaline medium
