A brass-mesh structured photoreactor applied in the photocatalytic degradation of RB5 dye

A photocatalytic structured reactor of calcined brass-mesh monolith immobilized with TiO2 was built for textile dye photodegradation. The photocatalytic efficiency of these materials was investigated at the reactive black 5 (RB5) degradation at a recycle reactor. The effects of feed flow (1, 2, and 3 L h-1), pH medium (4, 7, and 9), and the radiation source (solar and artificial) were studied. The results of the tests performed with artificial radiation (UV-A and UV-B) showed that the flow modification did not lead to a significant difference in the degradation of the dye chromophore group, thus proving the structured system characteristics when operating at high flow values. Regarding the radiation type, the use of solar radiation indicated a photocatalytic efficiency of 67.5%. The monolithic systems also showed good stability after 5 consecutive cycles of photocatalytic reaction, maintaining a degradation higher than 80%. It was observed that the toxicity tests of seeds and bacteria illustrated that the products obtained after the photodegradation were not toxic, guaranteeing the quality of water. Based on the results obtained in this work, the brass-mesh monolith consists of an efficient system for RB5 degradation, rising as a promising alternative to textile effluent treatment.

Automated summary

A photocatalytic structured reactor of calcined brass-mesh monolith immobilized with TiO2 was used for textile dye photodegradation. The effects of feed flow, pH medium, and radiation source on photocatalytic efficiency were investigated. The results showed that flow modification did not significantly affect the degradation of the dye chromophore group, and the use of solar radiation had a positive impact on photocatalytic efficiency. The monolithic system exhibited good stability and high degradation after consecutive cycles of photocatalytic reaction.