A systematic study on photocatalysis of antipyrine: Catalyst characterization, parameter optimization, reaction mechanism and toxicity evolution to plankton

• Published in: Water research (Oxford) 2017-04, Vol.112, p.167-175
• Main Authors: Gong, Han, Chu, Wei, Chen, Meijuan, Wang, Qinxing
• Format: Article
• Language: English
• Subjects: Antipyrine; Catalysis; Photodegradation; Photolysis; Plankton; Titanium - chemistry; Toxicity; Ultraviolet Rays; Water Pollutants, Chemical - chemistry
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2017.01.041

The toxicity of antipyrine (AP) in the photodegradation using UV/CoFe2O4/TiO2 was investigated by analyzing the characteristic of the catalyst, the effect of parameters (light source wavelength, catalyst dose, pH and initial AP concentration), the reaction mechanism (the organic intermediates, TOC reduction and inorganic ions release) and the newly proposed low-dosage-high-effective radical reaction approach. The catalyst shows the optimal removal efficiency under the conditions of wavelength at 350 nm, the catalyst dose at 0.5 g/L, and pH value at 5.5. Ten organic intermediates were identified, and five of them were newly reported in AP treatment process. Hydroxylation, demethylation and the cleavage of the pentacyclic ring were included in the decomposition pathways. The ring opening was certified by the 45% TOC reduction and 60% ammonia release during the process. The parent compound AP and its degradation products show positive effects on the growth of the algae. However, acute toxicity of AP was detected on brine shrimps Artemia salina. The toxicity was eliminated gradually with the decomposition of AP and the generation of the byproducts. The results indicate that the photocatalysis process is effective in AP removal, TOC reduction and toxicity elimination. [Display omitted] •UV/CoFe2O4/TiO2 was efficient in removal of antipyrine.•Ten organic intermediates, ammonia release, TOC reduction were detected.•Positive effect of antipyrine on algae growth was determined.•Acute toxicity of antipyrine to brine shrimps was eliminated by photodegradation.