Tetraacetylethylenediamine, commonly abbreviated as TAED, is an
organic compound 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 betwee ...
(CH
3C(O))
2NCH
2CH
2N(C(O)CH
3)
2. This white solid is commonly used as a
bleach activator
Bleach activators are compounds that allow a lower washing temperature than would be required otherwise to achieve the full activity of bleaching agents in the wash liquor. Bleaching agents, usually peroxides, are usually sufficiently active only ...
in laundry detergents and for paper pulp. It is produced by
acetylation
:
In organic chemistry, acetylation is an organic esterification reaction with acetic acid. It introduces an acetyl group into a chemical compound. Such compounds are termed ''acetate esters'' or simply '' acetates''. Deacetylation is the oppo ...
of
ethylenediamine
Ethylenediamine (abbreviated as en when a ligand) is the organic compound with the formula C2H4(NH2)2. This colorless liquid with an ammonia-like odor is a basic amine. It is a widely used building block in chemical synthesis, with approximately ...
.
Use and mechanism of action
TAED is an important component of laundry
detergent
A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are more ...
s that use "active oxygen" bleaching agents. Active oxygen bleaching agents include
sodium perborate,
sodium percarbonate, sodium perphosphate,
sodium persulfate, and
urea peroxide
Hydrogen peroxide - urea (also called Hyperol, artizone, urea hydrogen peroxide, and UHP) is a solid composed of equal amounts of hydrogen peroxide and urea. This compound is a white crystalline solid which dissolves in water to give free hydrogen ...
. These compounds release
hydrogen peroxide during the wash cycle, but the release of
hydrogen peroxide is low when these compounds used in temperatures below . TAED and
hydrogen peroxide react to form
peroxyacetic acid, a more efficient bleach, allowing lower temperature wash cycles, around . TAED was first used in a commercial laundry detergent in 1978 (
Skip by
Unilever). Currently, TAED is the main bleach activator used in European laundry detergents and has an estimated annual consumption of 75 kt.
Perhydrolysis
TAED reacts with alkaline peroxide via the process called perhydrolysis releasing of
peracetic acid. The first perhydrolysis gives triacetylethylenediamine (TriAED) and the second gives diacetylethylenediamine (DAED):
TAED typically provides only two equivalents of peracetic acid, although four are theoretically possible.
Competing with perhydrolysis, TAED also undergoes some
hydrolysis, which is an unproductive pathway.
Preparation
TAED is prepared in a two-stage process from ethylenediamine and acetic anhydride. The process is nearly quantitative.
[Europäische Patentanmeldung EPA 004 919, ''Verfahren zur Herstellung von N,N,N’,N’-Tetraacetyl-ethylendiamin'', Erfinder: G. Müller-Schiedmayer, R. Aigner, Anmelder: Hoechst AG, veröffentlicht am 31. Oktober 1979]
The
acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...
by-product is recycled as acetic anhydride.
Properties
Powdered TAED is stabilized by
granulation with the aid of the sodium salt of
carboxymethylcellulose (Na-CMC), which are sometimes additionally coated blue or green. Despite the relatively low solubility of TAED in cool water, (1 g/L at 20 °C), the granulate dissolves rapidly in the washing liquor.
The peroxyacetic acid formed has
bactericidal
A bactericide or bacteriocide, sometimes abbreviated Bcidal, is a substance which kills bacteria. Bactericides are disinfectants, antiseptics, or antibiotics.
However, material surfaces can also have bactericidal properties based solely on their ...
,
virucidal
A virucide (alternatively spelled viricide or named biocidal agent or known as microbicides or biocides) is any physical or chemical agent that deactivates or destroys viruses. The substances are not only virucidal but can be also bactericidal, fun ...
and
fungicidal
Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. A fungistatic inhibits their growth. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, ...
properties, thereby enabling TAED with percarbonate to
disinfect and
deodorize.
[Clariant Surfactant Division]
The Clean and Clever Way of Bleaching - PERACTIVE
(PDF; 865 kB), 08.99
Ecology
Triacetylethylenediamine is mostly non-toxic and easily biodegradable. TAED and its byproduct DAED have low aquatic
ecotoxicity. Triacetylethylenediamine shows a very low toxicity in all exposure routes, is practically non-irritating effect on skin and eye, and does not give any indication of skin sensitization. It is not mutagenic and not teratogenic.
[HERA Human & Environmental Risk Assessment on ingredients of European household cleaning products]
Tetraacetylethylenediamine (TAED), CAS 10543-57-4
(PDF; 666 kB), Draft, DECEMBER 2002. TAED, TriAED and DAED are all completely biodegradable and substantially removed during wastewater treatment.
[{{cite book, author1=Gilbert, P. A., editor1-last=de Oude, editor1-first=N. T., title=The Handbook of Environmental Chemistry, Vol. 3 Part F Antropogenic Compounds: Detergents, date=1992, publisher=Springer-Verlag, location=Berlin, isbn=354053797X, chapter=TAED-Tetraacetylethylenediamine]
References
External links
HERA RiskAssessment
Cleaning product components
Acetamides