abstract |
Disclosed are halide-free catalyst compositions for the disproportionation/isomerization of aromatic carboxylic acid salts. In one embodiment the catalyst comprises a mixed catalyst of compounds of copper, zinc, and zirconium; and, in a second embodiment, the catalyst comprises a copper compound treated with a base, optionally used with a promoter. Both halide-free catalysts provide advantages with respect to metallurgic problems, as well as good stability, activity and selectivity, and the later is faster kinetically at lower temperatures. |