Efficient self-photo-degradation of cationic textile dyes involved triethylamine and degradation pathway. (March 2021) - Li, Cheng-Bo
Abstract: Cationic textile dyes such as astrazon brilliant red (ABR), are frequently used in the textile industry and contaminait the water ecology. Photodegradation of such dyes in wastewater is considered as a promising method, while the existing approaches are usually involved complicated and costly materials as photocatalysts. Facial, effective and low-cost approaches for their decontamination are needed. What's more, the detailed decomposition path of ABR is not revealed. The present study shows that ABR could suffer effective self-photo-degradation under triethylamine treatment without a photocatalyst. Almost 100% of the dye degraded within 1 h under visible light irradiation. UV–vis, FTIR and UPLC-MS analysis conformed the degradation of ABR. Factors involved in the degradation system were investigated clearly. What's more, the accurate and detailed analysis of UV–vis, FTIR and UPLC-MS data combined with computational analysis revealed the decomposition process of ABR. Reactive oxygen species (ROS) was investigated from ROS trapping experiments and EPR measurements, which revealed that O2 − was the critical ROS in the degradation process, while 1 O2 and OH had slightly influence on the degradation progression. Highlights: Efficient self-photo-degradation of cationic textile dyes under TEA treatment was investigated for the first time. The degradation of single dye (0.5 mg/mL) in water reached almost 100% within 1 h. UV–vis, UPLC-MS, FTIR and computational analysis well revealed the degradation intermediates and pathways. Reactive oxygen species were well studied from both trapping experiments and EPR analysis.