Demonstration of aniline black dye

Chemicals needed

aniline    GSGiftig.gif (734 Byte) T GSUMWELT.gif (758 Byte)  N    R 20/21/22-40-48/23/24/25-50    S (1/2)-28-36/37-45-61

distilled water

sulphuric acid potassium dichromate solution GSGiftig.gif (734 Byte) T+ GSATZEND.gif (935 Byte) C GSUMWELT.gif (758 Byte)  N R 21-25-26-35-37/38-41-43-46-49-50/53    S (1/2)-26-45-53-60-61

Equipment needed

test tube

Test procedure


The residues can be disposed of as halogen-free organic waste. The dye residues can be largely removed with acetone or the like and a brush (caution!).


Through oxidative coupling aniline combines with itself, thereby forming chains of different lengths. Inasmuch as it is a matter of conjugated Pi-electron systems with various absorption maxima, the coloration covers the entire color spectrum. The structure of aniline black dye can be approximately described as:


Aniline black dye


to be added