Ozonation of Reactive Blue 81 in the bubble column.

The decolourisation process of the Reactive Blue 81 was carried out in a laboratory bubble column reactor with inner diameter 110 mm and working height 550 mm, equipped with a porous glass ozone diffuser (diameter 50 mm). A model of ozone absorption with the chemical reaction in the liquid phase was employed. It was found that the decolourisation proceeds in the fast pseudo first-order regime. The average value of the enhancement factor was calculated from the experimental results and compared with those calculated according to the theory of mass transfer with a second-order chemical reaction. In order to determine the intrinsic kinetics of ozonation, a stopped-flow technique was employed. The rate constant of the dyestuff reaction with ozone was determined as equal to 4.5 x 10(7) mol/(dm3.s).