Improvements in 1995 for the preparation of isophthalic acid or of terephthalic acid by catalytic oxidation of meta - or para - xylene

摘要

P preparation of isophthalic acid or of terephthalic acid by oxidation, respectively, meta - or para - xylene with molecular oxygen, at high temperatures and under conditions in the liquid phase in the presence of catalysts constituted by a combination of at least one oxidation catalyst based on transition metal (mn, co, this) and in the presence of a source of bromine. / p & & p & according to the invention, use is made of a liquid solvent system comprising essentially of benzoic acid and water in a proportion by weight of between 3% and approximately 15%. / p & & p & possibility of controlling an industrial scale, the value of the temperature of oxidation and to limit the fluctuations while obtaining a product which is very slightly coloured, a high degree of purity, quickly and at a high degree of conversion. / p