Acrolein

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Acrolein
IUPAC name Acrylaldehyde
Other names Acraldehyde
Acrylic Aldehyde
Allyl Aldehyde
Ethylene Aldehyde
Identifiers
CAS number [107-02-8]
SMILES C(=O)C=C
Properties
Molecular formula C3H4O
Molar mass 56.06 g/mol
Appearance Colorless to yellow liquid.
Irritating odor.
Melting point

-88 °C (-126 °F)

Boiling point

53 °C (127 °F)

Solubility in water Appreciable (> 10%)
Hazards
MSDS External MSDS[1]
Main hazards Highly poisonous. Causes
severe irritation to exposed
membranes. Extremely
flammable liquid and vapor.
NFPA 704
3
4
3
 
Flash point -26°C
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

In organic chemistry, the compound CH2=CH-CHO, more often called acrolein than the IUPAC name 2-propenal, is the simplest unsaturated aldehyde. It is produced widely but is most often immediately reacted with other products due to its instability and toxicity. It has a piercing, disagreeable, acrid smell similar to that of burning fat.

Contents

[edit] Synthesis

Acrolein is prepared industrially by oxidation of propene. Efforts are underway to use propane as feedstock for the synthesis, however, this is more difficult.[2] Several million tonnes of acrolein are produced each year.

When glycerol is heated to 280 °C, it decomposes into acrolein.[3] Acrolein may also be produced on lab scale by the reaction of approximately 1 part sodium bisulfate on 3 parts glycerine by weight.

[edit] Uses

Acrolein is used in the preparation of polyester resin, polyurethane, propylene glycol, acrylic acid, acrylonitrile, and glycerol. Acrolein tends to polymerize when left at room temperature, leaving a gummy yellowish residue with a putrid odor. It is also thought to be an intermediate in the Skraup synthesis of quinolines, but is rarely used as such due to its instability.

[edit] Health risks

Acrolein is a severe pulmonary irritant and lacrimating agent. It has been used as a chemical weapon during World War I. It is, however, not outlawed by the Chemical Weapons Convention. Acrolein is also a metabolite of the chemotherapy drug cyclophosphamide, and is associated with hemorrhagic cystitis. Skin exposure to acrolein causes serious damage. Acrolein concentrations of 2 ppm are immediately harmful. Acrolein is a suspected human carcinogen.[4] [5] In October 2006, researchers found connections between acrolein in the smoke from tobacco cigarettes and the risk of lung cancer.[6]

[edit] Acrolein test

Acrolein test is a test for the presence of glycerin or fats. A sample is heated with potassium bisulfate, and acrolein is released if the test is positive.[7] When a fat is heated strongly in the presence of a dehydrating agent such as KHSO4, the glycerol portion of the molecule is dehydrated to form the unsaturated aldehyde, acrolein (CH2=CH-CHO), which has the peculiar odor of burnt grease.

[edit] References