Creation and verfication of aniline

Chemicals needed

aluminium grits    GSLEICHT.gif (932 Byte) F   R 15-17    S (2)-7/8-43

distilled water

2-naphthol GSGESUND.gif (476 Byte) Xn  GSUMWELT.gif (758 Byte)  N    R 20/22-50     S (2)-24/25-61

Sodium hydroxide solution 7,5%  GSATZEND.gif (935 Byte) C    R 35     S (1/2)-26-37/39-45

sodium nitrite solutin, diluted GSGESUND.gif (476 Byte) Xn GSUMWELT.gif (758 Byte)  N    R 8-25-50     S (1/2)-45-61

nitrobenzene GSGiftig.gif (734 Byte) T GSUMWELT.gif (758 Byte)  N    R 23/24/25-40-48/23/24-51/53-62    S (1/2)-28-36/37-45-61

The raw product from Demonstration of nitrobenzene is sufficient.

hydrochloric acid 7%

One can also use other metals aside from aluminium, e.g., tin or iron. The acid concentration should be adjusted according to the fineness and activity of the metal.

Dangerous substance information

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

Equipment needed

2 test tubes
burner (preferably alcohol)

Test procedure


Both solutions can be disposed of as halogene-free organic waste.


Out of metal and acid a nascent hydrogen is formed. It reduces the nitro to an amino group. Due to the nitrous acid, which is released by the sodium nitrite and hydrochloric acid, it becomes a diazoate and couples in a alkaline milieu with the existing anionic 2-naphthol to 1-phenylazo-2-naphthol, which is colored a deep red. The orange coloring after the addition of the nitrite solution is possibly due to the formation of 1-nitroso-2-naphtol. If one manufactures nitrobenzene oneself, then one has traced the path from petroleum fraction to aniline dyes, a classic and important industrial process.


DSCN0465.JPG (198596 Byte)

The mixture before the beginning of the reaction.

DSCN0469.JPG (201338 Byte)

The mixture during the reaction.

DSCN0470.JPG (180652 Byte)

The mixture towards the end of the reaction.

DSCN0471.JPG (182808 Byte)

Verification of anline as a azo dye.


inspired by experiment 305, Reduktion von Nitrobenzen zu Aminobenzen (Anilin), p.179, [1]

and experiment 1971S, Anilin, p. 330, [2]

as well as Demonstration of orange II