Process for producing trimellitic acid

摘要

Pseudocumene is oxidized to obtain a reaction mixture comprising dimethyl benzoic acid (A), dimethyl benzyl alcohol (B) and dimethyl benzaldehyde (C), which are separated. The alcohol (B) is oxidized to obtain dimethyl benzoic acid (D) and dimethyl benzyl aldehyde (E), to which acid (B) and alcohol (C) are added. Dimethyl benzoic acid and/or benzaldehyde are oxidized to obtain trimellitic acid. The method involves oxidizing pseudocumene to obtain a reaction mixture comprising dimethyl benzoic acid (A), dimethyl benzyl alcohol (B) and dimethyl benzaldehyde (C). The dimethyl benzoic acid, dimethyl benzyl alcohol and dimethyl benzaldehyde are separated from the reaction mixture. Dimethyl benzyl alcohol (B) is oxidized to obtain dimethyl benzoic acid (D) and dimethyl benzyl aldehyde (E), to which dimethyl benzoic acid (A) and dimethyl benzyl alcohol (C) are added, respectively. Dimethyl benzoic acid and/or dimethyl benzaldehyde are oxidized to obtain trimellitic acid.