General Description
A clear colorless liquid with an overpowering fruity-like odor. Less dense than water. Flash point 15°F. Vapors are heavier than air.
Reactivity Profile
PROPIONALDEHYDE(123-38-6) may form explosive peroxides. Reacts vigorously with oxidizing agents. Explosive in the form of vapor when exposed to heat or flame [Lewis]. Incompatible with strong bases and strong reducing agents. Vigorous polymerization reaction with methyl methacrylate. Polymerization may also occur in the presence of acids or caustics .
Air & Water Reactions
Highly flammable. Soluble in water.
Hazard
Flammable, dangerous fire risk, explosive
limits in air 3.0–16%. Upper respiratory tract irri-
tant.
Health Hazard
Vapors will irritate nose and throat, and may cause nausea and vomiting. Liquid causes eye irritation.
Potential Exposure
Used as a synthetic flavoring; as
a disinfectant and preservative; to make propionic acid;
in plastic and rubber manufacturing; to make alkyl resins
and plasticizers.
Fire Hazard
Behavior in Fire: Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least 15
minutes, occasionally lifting upper and lower lids. Seek med-
ical attention immediately. If this chemical contacts the skin,
remove contaminated clothing and wash immediately with
soap and water. Seek medical attention immediately. If this
chemical has been inhaled, remove from exposure, begin res-
cue breathing (using universal precautions, including resusci-
tation mask) if breathing has stopped and CPR if heart action
has stopped. Transfer promptly to a medical facility. When
this chemical has been swallowed, get medical attention.
Give large quantities of water and induce vomiting. Do not
make an unconscious person vomit. Medical observation is
recommended for 24?48 hours after breathing overexposure,
as pulmonary edema may be delayed. As first aid for pulmo-
nary edema, a doctor or authorized paramedic may consider
administering a drug or other inhalation therapy.
Shipping
UN1275 Propionaldehyde, Hazard Class: 3;
Labels: 3-Flammable liquid.
Incompatibilities
Incompatible with strong acids; amines.
Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep away
from alkaline materials, strong bases, strong acids, oxoa-
cids, epoxides. Strong caustics; reducing agents can cause
explosive polymerization. Can self-ignite if finely dispersed
on porous or combustible material, such as fabric. Heat or
UV light can cause decomposition. Aldehydes are fre-
quently involved in self-condensation or polymerization
reactions. These reactions are exothermic; they are often
catalyzed by acid. Aldehydes are readily oxidized to give
carboxylic acids. Flammable and/or toxic gases are gener-
ated by the combination of aldehydes with azo, diazo com-
pounds, dithiocarbamates, nitrides, and strong reducing
agents. Aldehydes can react with air to give first peroxo
acids, and ultimately carboxylic acids. These autoxidation
reactions are activated by light, catalyzed by salts of
transition metals, and are autocatalytic (catalyzed by the
products of the reaction). The addition of stabilizers (anti-
oxidants) to shipments of aldehydes retards autoxidation
Chemical Properties
Propionaldehyde has a characteristic sharp and pungent odor similar to acetaldehyde.It undergoes reactions typical for the low molecular weight aldehydes, which, because of the terminal carbonyl group, are very reactive. Contamination or the exposure to elevated temperatures may induce a hazardous polymerization.
Propionaldehyde is a colorless, flammable liquid with a suffocating fruity odor. It is used as Intermediate for the chemical industry, for example for the manufacture of pharmaceuticals, pesticides, perfumes and plastics.
Occurrence
Reported found in apple aroma and in the essential oils of camphor, Rosa centifolia, clary sage, Pinus excelsa
and Pinus silverstris. Also reported found in over 100 natural products including apple, banana, sweet cherry, sour cherry, black
currant grapes, melon, pineapple, strawberry, cabbage, carrot, celery, cucumber, garlic, onion, leek, potato, peas, rutabaga, tomato,
Scotch spearmint oil, vinegar, bread and bread preferment, blue cheeses, cheddar cheese, Swiss cheese, butter, milk, cream, boiled
egg, caviar, fatty fish, cooked turkey, beef, pork and chicken, beer, rum, cognac, whiskies, grape wines, coffee, cocoa, tea, roasted
filberts and peanuts, peanut oil, potato chips, pecans, oats, honey, soybeans, Arctic bramble, beans, Bantu beer, plum brandy, cauliflower,
Brussels sprouts, rice, prickly pear, peated malt, clary sage, truffle, krill, oysters, loganberry, Chinese quince and maté.
Definition
ChEBI: An aldehyde that consists of ethane bearing a formyl substituent. The parent of the class of propanals.
Preparation
By oxidation of propyl alcohol, or by dry distillation of barium propionate with calcium formate.
Preparation
Propionaldehyde is prepared in the usual way by the oxidation of n-propyl alcohol. It can also be prepared by dehydrogenating the alcohol by passing the vapors over a heated copper or brass catalyst. This avoids the danger of further oxidation to propionic acid.
The reactions of propionaldehyde are practically like those of acetaldehyde. It must be remembered that only the two alpha hydrogen atoms are active in replacement and condensation reactions.
Flammability and Explosibility
Flammable
Biochem/physiol Actions
Taste at 5-10 ppm
Carcinogenicity
In a mutagenic test in V79 cells, Eder et al. observed
that propionaldehyde is not mutagenic at 1 mM, but is toxic at 2mM. Similar to acrolein, Eder et al. suggested that
the mutagenicity of this compound is mediated by its bifunctionality,
whereas its cytotoxicity is mediated by the aldehyde
function.
Purification Methods
the aldehyde with CaSO4 or CaCl2, and fractionally distil it under nitrogen or in the presence of a trace of hydroquinone (to retard oxidation). Blacet and Pitts [J Am Chem Soc 74 3382 1952] repeatedly distilled the middle fraction in a vacuum until it no longer gave a solid polymer when cooled to -80o. It is stored with CaSO4. [Beilstein 1 IV 3165.]
Waste Disposal
Propionaldehyde is destroyed by burning in achemical incinerator equipped with an afterburnerand scrubber. Permanganate oxidationis a suitable laboratory method of destruction.