The invention discloses a preparation technology of p-tert-butyl
benzoic acid, comprising the following steps: firstly, adding
toluene, isobutene and concentrated
sulfuric acid into a reaction kettle, carrying out
alkylation reaction to obtain coarse p-tert-butyl
toluene, and rectifying to obtain fine p-tert-butyl
toluene; secondly, adding a composite catalyst containing the p-tert-butyl toluene,
cobalt acetate and
bromide into the reaction kettle, heating and introducing
oxygen to obtain coarse p-tert-butyl
benzoic acid, decoloring by
activated carbon and diatomite , crystallizing and dryingto obtain fine p-tert-butyl
benzoic acid. The prepared p-tert-butyl benzoic acid is an
organic synthesis intermediate, can be used for the fields of additives, antioxidants,
alkyd resin modifying agents,
soldering fluid, dye, and the like of
polypropylene nucleating agents,
polyvinyl chloride heat stabilizers,
metal machining and lubricating oil and has excellent performance. The p-tert-butyl benzoic acid has low
energy consumption, high yield, simple separation, and the like and can satisfy ever-increasing market demands of the p-tert-butyl benzoic acid.