Oleochemicals are chemicals derived from plant and animal
fatsFats may refer to:*Fat, a generic term for a class of lipids in biochemistry*Fats Domino, rock and roll pianist*Fats Waller, jazz pianist*Fats Navarro, jazz trumpeter*Singing Fats, master of ceremonies*Obesity...
. They are analogous to petrochemicals derived from
petroleumPetroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
.
The formation of basic oleochemical substances like fatty acids, fatty acid methyl esters (FAME), fatty alcohols, fatty amines and glycerols are by various chemical and enzymatic reactions. Intermediate chemical substances produced from these basic oleochemical substances include alcohol ethoxylates, alcohol sulfates, alcohol ether sulfates, quaternary ammonium salts, monoacylglycerols (MAG), diacylglycerols (DAG), structured triacylglycerols (TAG), sugar esters, and other oleochemical products.
As the price of crude oil rose in the late 1970s, manufacturers switched from petrochemicals to oleochemicals because plant-based lauric oils processed from palm kernel oil were cheaper. Since then, palm kernel oil is predominantly used in the production of laundry detergent and personal care items like toothpaste, soap bars, shower cream and shampoo.
Industry in Asia
Southeast Asian countries' rapid production growth of
palm oilPalm oil, coconut oil and palm kernel oil are edible plant oils derived from the fruits of palm trees. Palm oil is extracted from the pulp of the fruit of the oil palm Elaeis guineensis; palm kernel oil is derived from the kernel of the oil palm and coconut oil is derived from the kernel of the...
and
palm kernel oilPalm kernel oil is an edible plant oil derived from the kernel of the oil palm Elaeis guineensis. It should not be confused with the other two edible oils derived from palm fruits: coconut oil, extracted from the kernel of the coconut, and palm oil, extracted from the pulp of the oil palm...
in the 1980s spurred the oleochemical industry in Malaysia, Indonesia, and Thailand. Many oleochemical plants were built. Though a nascent and small industry when pitted against big detergent giants in the US and Europe, oleochemical companies in southeast Asia had competitive edge in cheap ingredients. The US fatty chemical industry found it difficult to consistently maintain acceptable levels of profits. Competition was intense with market shares divided among many companies there where neither imports nor exports played a significant role. By the late 1990s, giants like
HenkelHenkel AG & Co. KGaA is an multinational company headquartered in Düsseldorf, Germany.The company operates in three business areas: Home Care , Personal Care ,...
,
UnileverUnilever is a British-Dutch multinational corporation that owns many of the world's consumer product brands in foods, beverages, cleaning agents and personal care products....
, and
PetrofinaPetrofina was a Belgian oil company which merged with Total in 1999 to form TotalFina, but the name has now been changed back to Total after another merger...
sold their oleochemical factories to focus on higher profit activities like retail of consumer goods. Since the Europe outbreak of 'mad cow disease' or (
bovine spongiform encephalopathyBovine spongiform encephalopathy , commonly known as mad-cow disease, is a fatal neurodegenerative disease in cattle that causes a spongy degeneration in the brain and spinal cord. BSE has a long incubation period, about 30 months to 8 years, usually affecting adult cattle at a peak age onset of...
) in 2000,
tallowTallow is a rendered form of beef or mutton fat, processed from suet. It is solid at room temperature. Unlike suet, tallow can be stored for extended periods without the need for refrigeration to prevent decomposition, provided it is kept in an airtight container to prevent oxidation.In industry,...
is replaced for many uses by vegetable oleic fatty acids, such as palm kernel and coconut oils.
Applications
The most common application of oleochemicals is
biodieselBiodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....
production. Fatty acids are esterified with an alcohol, commonly
methanolMethanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
to form methyl esters. Another common application is in the production of detergents.
Lauric acidLauric acid , the saturated fatty acid with a 12-carbon atom chain, is a white, powdery solid with a faint odor of bay oil or soap.-Occurrence:...
is used to produce sodium lauryl sulfate, the main ingredient in many personal care products. Other applications include the production of lubricants, green solvents, and bioplastics.
Hydrolysis
The fat splitting (or hydrolysis) of the
triglycerideA triglyceride is an ester derived from glycerol and three fatty acids. There are many triglycerides, depending on the oil source, some are highly unsaturated, some less so....
s produces
fatty acidIn chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s and
glycerolGlycerol is a simple polyol compound. It is a colorless, odorless, viscous liquid that is widely used in pharmaceutical formulations. Glycerol has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature. The glycerol backbone is central to all lipids...
:
- RCOOCH2–CHOOCR–CH2OCOR + 3 H2O → 3 RCOOH + HOCH2–CHOH–CH2OH
The addition of
baseFor the term in genetics, see base A base in chemistry is a substance that can accept hydrogen ions or more generally, donate electron pairs. A soluble base is referred to as an alkali if it contains and releases hydroxide ions quantitatively...
helps the reaction proceed more quickly.
Transesterification
If oils or fats are made to react with an
alcoholIn chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
(R'OH) instead of with water, the process is alcoholysis. It is also called
transesterificationIn organic chemistry, transesterification is the process of exchanging the organic group R″ of an ester with the organic group R′ of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst...
, because the glycerol fragment of the fatty acid tri-ester is exchanged for that of another alcohol. Thus, the products are fatty acid esters and glycerol:
- RCOOCH2–CHOOCR–CH2OCOR + 3 R'OH → 3 RCOOR' + HOCH2–CHOH–CH2OH
The fatty acid or fatty esters produced by these methods may be transformed. For example,
hydrogenationHydrogenation, to treat with hydrogen, also a form of chemical reduction, is a chemical reaction between molecular hydrogen and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically...
converts unsaturated fatty acids into saturated fatty acids. The acids or esters can also be
reducedRedox reactions describe all chemical reactions in which atoms have their oxidation state changed....
to give fatty alcohols.