Cetyl alcohol , also known as hexadecan-1-ol and palmityl alcohol, is a C-16
fatty alcohol
Fatty alcohols (or long-chain alcohols) are usually high-molecular mass, straight-chain primary alcohols, but can also range from as few as 4–6 carbon atoms to as many as 22–26, derived from natural fats and oils. The precise chain length vari ...
with the
formula
In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...
CH
3(CH
2)
15OH. At room temperature, cetyl alcohol takes the form of a
wax
Waxes are a diverse class of organic compounds that are lipophilic, malleable solids near ambient temperatures. They include higher alkanes and lipids, typically with melting points above about 40 °C (104 °F), melting to give lo ...
y white solid or flakes. The name cetyl refers to
whale oil
Whale oil is oil obtained from the blubber of whales. Oil from the bowhead whale was sometimes known as train-oil, which comes from the Dutch word ''traan'' ("tear drop").
Sperm oil, a special kind of oil used in the cavities of sperm whales, ...
(''cetacea'' oil, from , from ) from which it was first isolated.
Preparation
Cetyl alcohol was discovered in 1817 by the French
chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...
Michel Chevreul
Michel may refer to:
* Michel (name), a given name or surname of French origin (and list of people with the name)
* Míchel (nickname), a nickname (a list of people with the nickname, mainly Spanish footballers)
* Míchel (footballer, born 1963), ...
when he heated
spermaceti
Spermaceti (see also: Sperm oil) is a waxy substance found in the head cavities of the sperm whale (and, in smaller quantities, in the oils of other whales). Spermaceti is created in the spermaceti organ inside the whale's head. This organ may ...
, a waxy substance obtained from
sperm whale
The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the Genus (biology), genus ''Physeter'' and one of three extant species in the s ...
oil, with caustic potash (
potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash.
Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which utili ...
). Flakes of cetyl alcohol were left behind on cooling. Modern production is based around the
chemical reduction
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is ...
of
ethyl palmitate
Ethyl palmitate is an organic compound with the chemical formula C18H36O2. It is a colorless solid with a wax-like odor. Chemically, ethyl palmitate is the ethyl ester of palmitic acid.
Ethyl hexadecanoate is produced in aged whiskey, and is so ...
.
Occurrence and uses
The ether
chimyl alcohol
Chimyl alcohol is an organic compound with the formula . It is a colorless solid. Chimyl alcohol is a monoether formed by condensation of cetyl alcohol with one of the two primary alcohol sites of glycerol. Together with S-selachyl alcohol and ...
, derived from cetyl alcohol and glycerol, is a component of some
lipid membrane
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes form a continuous barrier around all cells. The cell membranes of almost all organisms and many viruses are made of a l ...
s.
Cetyl alcohol is used in the cosmetic industry as an
opacifier
An opacifier is a substance added to a material in order to make the ensuing system opaque. An example of a chemical opacifier is titanium dioxide (TiO2), which is used as an opacifier in paints, in paper, and in plastics. It has very high refract ...
in
shampoo
Shampoo () is a hair care product, typically in the form of a viscous liquid, that is formulated to be used for cleaning (scalp) hair. Less commonly, it is available in solid bar format. (" Dry shampoo" is a separate product.) Shampoo is use ...
s, or as an
emollient
A moisturizer, or emollient, is a cosmetic preparation used for protecting, moisturizing, and lubricating the skin. These functions are normally performed by sebum produced by healthy skin. The word "emollient" is derived from the Latin verb ''mo ...
,
emulsifier
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Althou ...
or
thickening agent
A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering their ...
in the manufacture of skin creams and lotions. It is also employed as a
lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, ...
for nuts and bolts, and is the active ingredient in some "liquid pool covers" (forming a non-volatile surface layer to reduce water evaporation, related
latent vaporization heat loss, and thus to retain heat in the pool). Moreover, it can also be used as a non-ionic co-
surfactant
Surfactants are chemical compounds that decrease the surface tension or interfacial tension between two liquids, a liquid and a gas, or a liquid and a solid. The word ''surfactant'' is a Blend word, blend of "surface-active agent",
coined in ...
in
emulsion
An emulsion is a mixture of two or more liquids that are normally Miscibility, immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloi ...
applications.
Side effects
People who have
eczema
Dermatitis is a term used for different types of skin inflammation, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened ...
can be sensitive to cetyl alcohol, though this may be due to impurities rather than cetyl alcohol itself. However, cetyl alcohol is sometimes included in medications used for the treatment of eczema.
Related compounds
*
Palmitate
Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Li ...
*
Palmitic acid
Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The ...
References
{{alcohols
Fatty alcohols
Antioxidants
Non-ionic surfactants
Lubricants
Cosmetics chemicals
Whale products
Primary alcohols
Alkanols
Semiochemicals
Insect pheromones