EVALUATION OF PHOTOCATALYTIC REACTORS FOR DEGRADATION OF REACTIVE BLACK DYE 5 IN THE PRESENCE OF TiO2 (Atena Editora)

Abstract

In this work, two types of reactors were evaluated (tubular and tank) under different experimental conditions (with and without aeration and temperature control) to degrade the textile dye Reactive Black 5 (PR5), using TiO2 as a photocatalyst. A jacketed tubular reactor made of PVC and a glass cylinder was used, equipped with a 36 W Hg lamp (submerged in the contaminant solution), temperature control and aerator, and a second tank-type reactor equipped with two Hg lamps (15 and 36 W) located above the contaminating solution. In experiments carried out in the tubular reactor without temperature control, discoloration results were 99% (with aeration) and 87% (without aeration). The values obtained for reactions with temperature controls were 55% (10 °C), 95% (25 °C) and 99% (35 °C). PR5 photolysis reactions showed that the dye discolored by approximately 4, 25 and 35% in experiments carried out at 10, 25 and 35°C, respectively. For the reactions in the tank reactor, the discoloration of PR5 during the photocatalytic reactions carried out with and without aeration was around 22%, while the dye photolysis reactions did not reach 1% discoloration. Therefore, it can be concluded that the tubular reactor is more efficient for the degradation of PR5, since the UV lamp immersed in the dye solution and the design of the reactor favor the reaction and aeration of the system, which are important factors for the best performance of a photocatalytic reactor.