Disclosed is a process to produce a purified carboxylic acid product. The
process comprises removing impurities from a crude carboxylic acid slurry
in a solid-liquid displacement zone to form a slurry product. The slurry
product if further treated in a staged oxidation zone and a
crystallization zone to from a crystallized product. The crystallized
product is further cooled in a cooling zone and subsequently filtered and
dried in a filtration and drying zone. The process produces purified
carboxylic acid product having good color and low impurity levels without
the use of purification steps like hydrogenation.