Combined photocatalytic and biological process for textile wastewater treatments

Abstract

Azo dyes, common in textile wastewater, have high photolytic and chemical stabilities, which make them difficult to be removed using conventional treatments. This study aims to evaluate a combined process using heterogeneous photocatalysis, with ZnO/UV or TiO 2 /UV (0.6 g catalyst L −1 solution/2-hr UV radiation), and a biological process for textile wastewater treatment. After the proposed treatments, the color and organic matter removals from synthetic wastewater (SW) and industrial wastewater (IW) were evaluated. For SW, the coupled photocatalytic (ZnO/UV or TiO 2 /UV)-biological system promoted a high extent of color removal (98%) and total organic carbon (TOC) reduction (>80%). Promising results were obtained with IW using combined photocatalytic (TiO 2 /UV)-biological treatments, reaching 97% and 63% of color and TOC removal, respectively. This process, coupling heterogeneous photocatalysis and a bioprocess, has proved to be a good alternative for the treatment of textile wastewater, not only for color removal but also for dye mineralization purposes. • Practitioner points• A combined process using heterogeneous photocatalysis (ZnO/UV or TiO 2 /UV) and biological process was evaluated for synthetic (SW) and industrial (IW) textile wastewaters treatment. • For SW, coupled process promoted high extent of colour and organic matter removals. • For IW, promising results were obtained with TiO 2 /UV-biological treatment (97% of colour and 63% of organic matter removals).

Thermophysiological comfort of sonochemically synthesized nano TiO2 coated woven fabrics

“…The applications of TiO 2 varies from sunscreens to paints and waste water treatment to self-cleaning performance 16 . Many researchers have reported successful coating of TiO 2 on textiles for photocatalytic applications [17][18][19][20][21][22][23] . Sonication (utilization of ultrasonic energy) has shown its potential as a facile, economical and eco-friendly method for the fabrication of nanostructures and their deposition on textiles 24 .…”

Textile Industry Effluent Treatment Techniques

“…Hybrid biological and chemical treatment methods to remove Reactive Red 180, Reactive Black 5, and Remazol Red RR dyes from water have been reported by [96]. Removal of different dyes such as the reactive azo dyes Red Intracon CD-3SR, Yellow Reactron 4GL, and Navy Blue Intracon US-B Ultra with integrated biological and chemical treatment methods have also been reported [97]. Some researches were reported by H 2 O 2 [91], photo-Fenton [92], and ozonation [93].…”

Textiles wastewater treatment technology: A review

“…In another study, Silva, Gonçalves, and Raddi De Araujo (2019) treated both synthetic and industrial textile wastewater using integrated biological processes with ZnO/UV or TiO 2 /UV photocatalysis technology. The research resulted in >80% of total organic carbon and 98% of color removal.…”