Ferroin in dyes degradation by Fenton-like process: a chemical waste recycling perspective

Author(s)

Nunes, William Bardelin ^[1] ; Dantas, Renato Falcao ^[1] ; Fagnani, Enelton ^[1]

Affiliation

^[1] Univ Campinas FT UNICAMP, Sch Technol, Res Grp Optimizat Analyt Technol Appl Environm &, Rua Paschoal Marmo 1888, BR-13484332 Limeira, SP - Brazil

• Document type: Journal article
• Source: WATER SCIENCE AND TECHNOLOGY; v. 84, n. 5 AUG 2021.
• Web of Science Citations: 0

Abstract

Literature describes the formation of Fe (II)-phenanthroline complex (ferroin) as a stop way for Fenton processes, ceasing radicals yielding. Antagonistically, this study presents evidences that ferroin can be activated by UVA in mildly acidic media in photo-Fenton-like process. Because ferroin is the main waste from total iron determination in environmental samples, a recycling approach is suggested. Based on the best practices of waste management planning, an application of the proposed method for treating another chemical waste is presented. Titrimetric ammonia determination waste containing 2.67 mg L-1 methyl red azo dye and 1.33 mg L-1 methylene blue was degraded at the optimized experimental conditions: pH = 5.2-5.4; {[}H2O2] = 310 mg L-1; {[}Ferroin] = 1.4 mg L-1; temperature = 36 1 degrees C; reaction time = 165 min under UV-A irradiation. Attenuation of most intense spectroscopic bands for the dyes achieved 94% (510 nm) and 96% (665 nm) for methyl red and methylene blue, respectively, with degradation of ferroin itself. The present work brings empirical evidence that is possible to recycling ferroin as photo-Fenton-like process catalyst, besides to determine the best conditions for providing less acidic treated effluents with negligible suspended solid concentration, better than obtained from classical photo-Fenton processes. HIGHLIGHTS Ferroin can act as catalyst in photo-Fenton-like processes. Degradation of azodye by modified Fenton treatment. Drawbacks from classical Fenton processes are mitigated. Waste acting as catalyst for treating another waste. Improvement for institutional waste management plan. (AU)

• FAPESP's process: 18/02507-9 - 10th SPEA - European Meeting on Solar Chemistry and Photocatalysis: Environmental Applications
• Grantee: Enelton Fagnani
• Support Opportunities: Research Grants - Meeting - Abroad
• FAPESP's process: 16/50460-6 - Removal of emerging contaminants during disinfection of urban wastewater by advanced oxidation
• Grantee: Renato Falcão Dantas
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/17774-1 - Influence of the secondary effluent composition on the disinfection by advanced oxidation processes
• Grantee: Renato Falcão Dantas
• Support Opportunities: Research Grants - Young Investigators Grants