Nitric Acid → Naphthalene

Participants

Reaction Steps

The industrially important 8-nitronaphthalene-1,3,5-trisulphonic acid is prepared by nitrating the naphthalene-trisulphonic acid mixture which is obtained in the trisulphonation of naphthalene with sulphuric acid and oleum and which contains naphthalene-1,3,5-trisulphonic acid as the main constituent, with nitric acid using sulphuric acid as the solvent (see F.I.A.T. Final Report No. 1016, pages 42-44). According to this process, the hot solution, of the naphthalenetrisulphonic acids in sulphuric acid, which has a temperature of 90° C. and is obtained in the trisulphonation of naphthalene is transferred to the nitration kettle and, after cooling to 60° C., diluted with water and nitrated with mixed acid (86% of nitric acid, 12% of sulphuric acid and 2% of water) at 30° to 35° C. The nitration mixture is subsequently stirred at 40° C. for 1 hour. As a repetition of the process has shown, the yield of 8-nitronaphthalene-1,3,5-trisulphonic acid is only about 46%, relative to the naphthalene-1,3,5-trisulphonic acid employed (see Example 16 of the present Application).

Provenance & Evidence