Basic Red 18 is a cationic
azo dye
Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N ...
used for coloring textiles. The
chromophore
A chromophore is the part of a molecule responsible for its color.
The color that is seen by our eyes is the one not absorbed by the reflecting object within a certain wavelength spectrum of visible light. The chromophore is a region in the molec ...
is the cation, which contains many functional groups, but most prominently the
quaternary ammonium
In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations ...
center.
It is produced by azo coupling of 2-chloro-4-nitrophenyl
diazonium cation with the quaternary ammonium salt derived from
N-ethyl-N-(2-chloroethyl)aniline and
trimethylamine
Trimethylamine (TMA) is an organic compound with the formula N(CH3)3. It is a colorless, hygroscopic, and flammable tertiary amine. It is a gas at room temperature but is usually sold as a 40% solution in water. (It is also sold in pressurized ...
.
[.]
Like many dyes, methods for the removal of Basic Red 18 from waste streams has received much attention.
References
Anilines
Azo dyes
Nitrobenzenes
Quaternary ammonium compounds
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